bachelor neurolinguistics agingbrain
TRANSCRIPT
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STAUDACHER Veronika Bachelorarbeit
Matr.Nr. a6802339 Neurolinguistics
A 033 Bachelorstudium Prof. Dr. Susanne Reiterer
612 English and American Studies
LANGUAGE LEARNING WITH AN AGING BRAIN
"Was Hnschen nicht lernt, lernt Hans nimmer mehr.
July 2011
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Table of contents
1 Introduction and definitions ..................................................................................... 3
2 Brain development and aging factors.................................................................... 6
2.1 Changing brain structures ................................................................................... 6
2.2 Neuronal changes............................................................................................... 11
2.3 Chemical changes in brain ................................................................................ 11
2.4 Genetic factors ....................................................................................................14
2.5 Environmental influences ..................................................................................14
2.6 Impairments and aging diseases......................................................................16
3 Language learning in later adulthood .................................................................. 18
3.1 Aging factor ..........................................................................................................20
3.2 Intelligence and aptitude....................................................................................23
3.3 Education .............................................................................................................24
3.4 Motivation to learn a language..........................................................................25
3.5 Learning styles ....................................................................................................27
4 Use it or lose it successful language learning as older adult ..................... 28
4.1 Delaying the effects of brain aging...................................................................29
4.2 Prerequisites of language learning ..................................................................32
4.3 Strategies for language learning 60+ ..............................................................33
5 Conclusions and future prospects ....................................................................... 35
6 Bibliography ............................................................................................................. 38
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1 Introduction and definitions
The demographic share of older people is increasing. They gain importance in
economic fields as well as in health industry, not to forget in education and lifelong
learning.
The following chapters will deal with aging 1 people, their aging brains and how
their learning, especially learning of a (second) language, can be managed.
Actually, in this paper the main focus will be on situations and possibilities in the
late adulthood. What does aging mean in this context? What is the difference
between childhood, youth, adolescence, adulthood and old age?
Traditionally, we divide human lifespan in three major parts: infancy and childhood,
adolescence (teenager), adult life and old age or late adulthood. Up to now old
age is linked in our perception with retirement from active professional life. In
modern societies there seems to be a change towards more phases in ones life.
E.g. concerning the occupational history the former lifelong service in one
company is nowadays often interrupted for continuing education, sabbaticals or
childcare. What is of interest for this paper and has also great influence on the
demographic development of our society is that the late adulthood (60+) has
prolonged to such an extent during the last decades that this age period can be
divided again into three stages, the young old, middle old and the old old.
Nowadays, the average life expectancy of women in Austria is 82.9 years and 77.4
of men (http://www.statistik.at/web_de/statistiken/soziales/gender-statistikdemographie/
1 ageing
BE, aging
AE. As the great majority of studies and references use the American version, we
also stick to it in this paper.
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043903.html, 14.7.2011). In other words, there is enough time to decide on an
active life after retirement, e.g. on learning a language, because if a women retires
at the age of 60 there still remain more than 20 years of a hopefully fulfilled life.
In other contexts we find the term 50+generation or the golden fifties when they
speak about the groups starting with the young old who are going towards the end
of their work life or will retire soon. These mentioned groups usually are in good
health conditions, are still very active and are open for changing environments. But
they show differences according to their gender, their level of education and the
culture in which they grew up (Ohly 2007: 87, Kimerstorfer 2007: 22-23, 25). A
survey by Fessel & GfK in 2006 classifies four types of members of the
50+generation, namely the Curious, the Happy, the Lively and the
Withdrawn (Fessel & GfK 2008: 7). This means that 74 percent (the Curious, the
Happy, the Lively) feel healthy and fit enough to lead an active life, including
learning something new.
Furthermore, we will have to dedi-
cate growing interest to the recent
demographic development showing
an increasing percentage of older
population and a decrease of the
younger age groups. If this long-term
development will continue the older
generation will form the majority, at
least in Western, industrialised so-
cieties. This trend, lasting since the Figure 1: Population pyramid for Austria 2006, 2030 and
2050
Source: Statistik Austria 2011
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beginning of the 20th century, has two reasons: One is the decreasing birth rate,
the other is the fact that people become older and die later, as already mentioned
above (Nandy 1977: 2, Kimerstorfer 2007: 24). As a result of the mentioned facts
and developments, a great number of sciences have been dealing with aging, with
the development of the human brain, with communication and language in this
context: biology, medicine, psychology, sports, economic sciences, cultural
sciences, demographics and even theology. The most recent ones are gerontology
(the study of the aging process as such) and geragogy (concentrating on
education / teaching of the elderly; on lifelong learning) (Berndt 2003: 9, Ohly
2007: 86-87, Kimerstorfer 2007: 76-78).
Biologically, the period of early adulthood is said to be the culmination point of
human productivity, but the human brain is already declining after puberty, it is
aging. But fact is that aging could also be manifested right after birth if we
describe it as lifelong process of changes, of maturation during the first third of
lifespan, and of decline and degeneration the time afterwards till death (Seeberger
2011: 2). If this holds true also for the main organ we have, the brain, and for our
main communication tool, our language, then we have to speed up and learn as
much as we can as early as possible. To learn more about these correlations and
interrelations, the following chapter will deal with the human brain and its
development over lifespan and how it is changing towards older age. The
subsequent section will have a look at lifelong learning in general and in particular
on language learning in older age. The paper will close with strategies to delay the
effects of brain aging and thus also encourage (second/third) language learning as
50+ or even in late adulthood (60+).
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2 Brain development and aging factors
Behavioral research has found out at least three patterns of age-related changes
in cognitive development: life-long declines, late-life declines and life-long stability.
In longitudinal as well as cross-sectional studies more or less steady decline is
found for cognitive skills like working/episodic memory, processing speech, spatial
ability or reasoning. After the age of 60 decline shows acceleration in some fields
e.g. the speed of processing. What is most interesting here is the fact that there is
an acceleration of decline in cognitive activities 3 6 years before death. On the
other side, the late life decline especially of short-term memory is distinct after the
age of 70. Furthermore, study results report on a relative stable semantic memory
until late lifetime. Researchers conclude that life experience backs up knowledge,
and the result is wisdom often observable with older persons (Hedden & Gabrieli
2004; 88 89).
When the former president of the US George Bush Sr. proclaimed the decade of
the brain to enhance public awareness of the benefits to be derived from brain
research" in 1990 a great number of activities with following publications and
programs was initiated (Sprenger 1999: 100, Janich 2009: 101). Since then
cognitive neuroscience of aging has been more and more engaged with the
question about age-related changes in neural structures of the brain and their
effects on learning (Hedden & Gabrieli 2004; 88 89).
2.1 Changing brain structures
Many studies affirm that structural changes are to a certain extent normal but can
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become pathological thus being the result or the cause of age-related diseases.
Firstly, post mortem and in vivo studies (fMRI) tend to confirm that older adults
have less grey matter in brain than younger ones. This means that there is a
decrease in brain volume in general and a loss of weight of individuals brains
especially over the age of 60.
In general, neuron loss or shrinkage is said to cause only 10 % reduction each
decade in the total length of myelinated axons of the brain. Other studies report on
volume losses in the cerebral cortex of 14 % over the age of 30 90 years, of 35
% in the hippocampus and of 26 % of the cerebral white matter, again with the
highest loss after the age of 50 (Anderton 2002: 811 - 812, Hedden & Gabrieli
2004; 88 89).
Former studies wanted to confirm that neuron loss in the aged brain is not so
dominant and neuron loss takes
place only in specific regions
(Rapp & Gallagher 1997: 14). But
anyway, aging is associated with
brain shrinkage, mainly in the
regions of the association cortex,
striatum and cerebellum, but shrinkage of white matter and hippocampus is
accelerating not until older age (Raz et al. 2007: 91). In addition, recent studies
report that the reason for loss of volume in certain brain areas probably does not
result from cell death, but rather from lower synaptic density in older adults,
which declines steadily from the age of 20 years onwards and which is one of the
markers of Alzheimer disease (Hedden & Gabrieli 2004: 89).
Figure 2: Progressive changes in neurons of prefrontal cortex with aging
Source: Nandy 1977: 41
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In detail, a major region for age-related changes affecting volume and functions is
the frontostriatal system including the prefrontal cortex and the basal ganglia
where motor, cognitive (language, memory, reasoning) and emotional actions are
interconnected and regulated. The estimated average decline in the structure of
the prefrontal cortex is about 5 % per decade, beginning with the age of about 20.
As motor control is highly relevant for speech production, i.e. for the impulses
needed for muscles in and around the mouth to formulate the appropriate sounds
of speech, the age-related changes in these areas can have negative effects on
articulation (Singleton 1995: 32, Bongaerts 1999: 135, Singleton 2004: 84, Hedden
& Gabrieli 2004; 89, Herschensohn 2007: 12).
Moreover, the white matter tracts in frontal lobes also show an age-related loss of
integrity what could have negative effects on memory circuits. In addition,
Parkinsons and Alzheimers patients show lesions and loss of volume in the
entorhinal cortex, located in the medial temporal lobe and being the main interface
to the hippocampus which has an important role in transferring information from
short-term memory to long-term memory, a very important aspect in language
learning. On the other hand, the decline of the structures of the hippocampus and
the parahippocampal gyrus is said to be 2 3 % per decade, increasing up to 1 %
per year after the age of 70.
As the below mentioned changes happen gradually and may start more than a
decade before Alzheimers disease, emerging cognitive impairments during this
period could be used for predicting progression from healthy (normal aging) status
to Alzheimers disease (Hedden & Gabrieli 2004; 89 - 92).
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Senile plaques:
Moreover, senile plaques are also an age-related change, namely the abnormal
deposit of amyloid, a protein, which is deposited outside the neuron in the grey
matter of the brain often surrounded by abnormally swollen neurits. Plaques often
occur in the amygdala and in the sulci of the cortex, but rarely in the cerebellum.
Plaques are of various shape and size and are known as markers for Alzheimers
disease where the number of the plaques has greatly increased compared to a
normal aging brain where only a few plaques could be found (Anderton 2002:
814). Women are said to have slightly more plaques than men and generally the
proportion of people with plaques increases from about 10 % at the age of 60 to
more than 60 % with 80 years. Interestingly, there are elderly persons having
varying degrees of amyloid plaques but do not show any clinical abnormalities
compared to cohorts without any amyloid deposits (Dickson 1997: 55 69).
Neurofibrillary tangles:
Neurofibrillary tangles, which are decayed portions of the dendrites and are
aggregates of a tau protein, are significant markers of AD. In normal aging the
number of tangles is relatively low and can be found only in hippocampus,
amygdale and entorhinal cortex whereas in strongly demented persons the
neurofribriallary tangles are widespread (Anderton 2002: 814). Under electron
microscope we recognize an entanglement of spiral twisted protoplasm-threads in
these areas. The precise mechanism of tangle formation is not completely
understood, and it is still controversial whether tangles are a primary causative
factor in disease or play a more peripheral role. Anyway, large numbers of senile
plaques and neurofibrillary tangles are characteristic features of Alzheimers
disease (de Leon 2007: 116 - 117).
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Blood vessels:
Furthermore, we must not forget the possible changes of blood vessels in the
brain caused by different reasons and with various effects because the saying
one is as old as ones arteries provides a remarkable truth. PET studies have
found that also cerebral blood flow in the white and grey matter declines during
normal aging and with it the rate of oxygen supply. Reasons could be structural
changes in the cerebral vessels in connection with thrombotic, infarcted or
infectious occasions. Furthermore, diseases associated with artherosclerosis,
hypotension, diabetes, heart disease could also affect the cerebral blood supply
(de la Torre 1997: 78-80).
Metabolism:
In this connection we must mention the fact that also the cerebral metabolism
tends to slow down with age. This is affirmed by PET as well as fMRI studies
concerning measurements of the rate of glucose or of oxygen as well as of
cerebral blood flow in general. The less the brain is affected by cardiovascular
diseases the less is the degree of reduction in cerebral metabolism and blood flow
(Blass, Gibson & Hoyer 1997: 111, Mechelli 2004: 583 - 585).
To sum up we can say that normal aging does not necessarily lead to cerebral
dysfunction. On the other hand, there is an increasing number of studies reporting
that changes in signal transmission between the neurons are responsible for age-
related cognitive deficits, rather than structural alterations (Gazzaley & DEsposito
2006: 68).
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2.2 Neuronal changes
Our brain is said to consist of more than 100 billion cells, most of them being
neurons, the cells of the nervous system, which is responsible for transmission of
impulses to and from the brain supposedly at a rate about 200 miles per hour. The
nerve cells remain healthy until death, unless one has a specific disease
(Guttmann 2001: 1). In detail, the neuronal cytoskeleton remains preserved, only
smaller alterations are detected in some proteins associated with microtubules,
neurofi laments and microfilaments. The cause might be oxidative stress,
excitotoxicity or metabolic impairment. Concerning age-related late-onset brain
diseases like Alzheimers or Parkinsons severe changes in the cytoskeleton are
symptomatic (Geddes & Matus 1997: 24 39).
Furthermore, myelin degeneration which is observable already in earlier age, but
increases with later age could be the cause for age-related cognitive and motor
slowing. This process is often accompanied by a granular degeneration of myelin
what could be the consequence of oxidative damage to macromolecules (Dickson
1997: 53).
2.3 Chemical changes in brain
Due to recent improved research methods like use of fMRI (functional magnetic
resonance imaging) or PET (positron emission technology) researchers have
enough evidence to state that cognitive decline is not due to neuron loss but has
to do with changes in chemical interactions in brain. They examined brains of
elderly people after their death and found numerous plaques and tangles typical
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for Alzheimers disease but none of them had suffered from Alzheimerss
(Guttmann 2001: 2).
Neurotransmitters:
Cell to cell signals are sent by electrical conduction and chemical stimulation of
surface receptors. These chemical signals are transported by neurotransmitter
substances (Kelly & Roth 1997: 243, Janich 2009: 53). A number of researchers
have postulated that deficits in neurotransmission may have an effect on age-
related learning and memory, as well as motor function, and that those deficits
may have influence on the development of neurodegenerative diseases. For
instance, the neurotransmitter dopamine, also called the happiness hormon, was
found in the substantia nigra, the midbrain and the hypothalamus. It plays a role in
transporting motor control signals, but also signals concerning learning and
memory, furthermore it is responsible for transporting pleasure and reward. The
degree of its availability is said to be a marker for aging, but concerning the
electric and chemical effects much more research is needed (Kelly & Roth 1997:
251 252). Recent findings confirm a decline of dopamine of about 8 % per
decade starting after the 4th decade which is connected e.g. with a lower glucose
metabolism in the frontal cortex. Furthermore, serotonin receptors also decline in
the frontal cortex with age and dopamine receptors in the subcortical striatum.
(Hedden & Gabrieli 2004: 90).
Free Radicals:
For a long time and sti ll under debate is the free-radical theory of aging. It states
that the organisms age because cells accumulate free radical damage over time
(http://en.wikipedia.org/wiki/Free-radical_theory_of_aging, 17.7.2011). Free radicals are
produced during oxygenation of organic substances. Some free radicals are highly
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reactive and are supposed to be involved in the reduction of cell membrans, of
collagen, of elastin and other elements. Even more severe is the likely effect of
free radicals on DNA causing the formation of unstable substances which in turn
can alter the DNA structure so that mutant proteins form imperfect enzymes
having a negative effect on cells (Nandy 1977: 1-2, http://en.wikipedia.org/wiki/Free-
radical_theory_of_aging, 17.7.2011).
Researchers have found out that antioxidants such as vitamin A, vitamin C,
vitamin E can slow the process of aging by preventing free radicals from oxidising,
or can even reduce the formation of free radicals. These antioxidant chemicals
found in many foods are frequently cited as the basis for fighting this risk factor.
Nonetheless, some recent studies tend to show that such an antioxidant therapy is
not useful (Nandy 1977: 4, Muller 2007: 495).
Estrogen replacement:
A broader debate in the context of chemical influences is going on about the
estrogen replacement therapy in healthy post-menopausal women. The reason for
this measure is that estrogen (the primary female sex hormone) is supposed to
increase cerebral blood flow and to accelerate metabolism which has an effect on
prolonged vitality and functionality of cerebral neurons (de la Torre 1979: 91 -
92). Studies during the 1990ies show evidence that women who have used
estrogen replacement have better naming abilities with advancing age, alongside
a decreased risk of Alzheimers disease (Obler & Gjerlow 1999: 161 162).
As chemical reactions or structural changes in brain do not happen to everybody
in older age or at least do not occur at the same pace their occurrence might be
also due to genetic factors and might be influenced by human development.
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2.4 Genetic factors
During evolution of the human brain over more than 100.000 years for a long time
the maximum age of humans was about 40 or 50. Only during the last millenniums
and especially in the past centenaries people are constantly growing older and
reach an old age of more than 70 or 80 years mainly due to better live conditions
and higher education. This might be the reason why all brains decline with aging
because there was no evolutionary selective pressure in former eras (Guttmann
2001: 3).
As Robert Tan from the Mens Health Network at the University of Texas-Houston
states having good parents certainly helps: your genes determine how long you
are going to last (http://www.zirh.com/optimal%20aging.aspx, 23.7.2011). Studies
have proved that certain proteins in the brain like e.g. apolipoprotein E4 can be
genetic risk factors for memory decline, especially for the development of AD.
Therefore researchers think that genetic factors have an impact on the functional
decline of the brain. Furthermore, it is likely that a combination of genetic and
environmental factors might determine whether a person is destined to get AD or
not, independent from age (Anderton 2002: 811, 813).
2.5 Environmental influences
Recent findings and also practical experiences show that the aging of brain can be
speeded up or slowed down by lifestyle factors.
Lifestyle:
Restricted weight lowers the blood glucose level. Glucose is very reactive as a
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chemical and can cause damage to proteins. Especially those individuals with
diabetes show more signs of brain aging than non-diabetic [ones] (Guttmann
2001: 3).
Education:
Those who use it [the brain], dont lose it as quickly is the resume of numerous
studies. Constantly using cognitive patterns could make the synopses stronger or
even create new neurons (Guttmann 2001: 3).
Exercise:
People walking rapidly min 45 minutes a day show significantly improved age-
related cognitive abilities (Guttmann 2001: 3).
Stress:
Under stress the human body produces the hormone cortisol which in small
dosage can improve memory, but in larger amounts has a negative, depressing
effect on our immune system (Guttman 2001: 4).
Sleep/Rest:
Sleep of at least 8 hours per night helps protect against age-related chronic
illnesses including memory loss. (Guttmann 2001: 3).
But certainly there is no guarantee that we can keep our brain in top condition if
we avoid all the above mentioned negative environmental influences . At least the
consequences of aging in the brain and the central nervous system could be
slowed down, in fact the earlier one starts with lifestyle improvements the larger
can be the impact on delaying brain aging (Guttman 2001: 4).
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2.6 Impairments and aging diseases
A short overview of the main brain diseases and impairments in later adulthood will
help to understand why most of the affected persons have massive problems in
performing cognitive processes.
Alzheimers disease (AD):
Dementia among elderly can have various
reasons, but Alzheimers disease is the
commonest. The onset of Alzheimers disease is
difficult to diagnose reliably. Only post mortem
inspections clearly show a large amount of the
characteristic plaques and neurofibrillary tangles
in certain brain areas. Also synapse loss is
extensive in AD and this process can start early in
age (Baddeley 1998: 321 322, Hof & Morrison
2004: 611). Especially during the early stages of AD the symptoms can vary from
patient to patient and can comprise problems with orientation concerning time and
place, memory and language blackouts, decrease of visual abilities and attention
and gradual loss of competence in problem solving and social functions.
Furthermore, personality changes are a symptom in a later stage of the disease
(Baddeley 1998: 322, Obler & Gjermow 1999: 91).
Parkinsons disease:
Most of the Parkinsons diseases are caused by subcortical cellular changes.
Patients have problems with walking and speech, at least in starting to carry out
these movements. Their speech elements may end up in stumbling, and also their
Figure 6: Causes of dementia in later life Percentages in this diagram based on a study in the US in 1992
Source: Baddeley 1998: 323
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writing will be disturbed. These impairments are caused by loss of muscle control
but usually there is no damage to language areas in the brain. This form of
dementia shows primari ly problems with memory and with recalling stored
knowledge. The cause is said to be an insufficient distribution of dopamine to the
frontal lobe, a central region for language production (Obler & Gjerlow 1999: 91
94).
Aphasia and dementia:
Both aphasic and demented patients produce some speech elements but often
with disturbed forms or unusual elements. With aphasics there is often a sudden
onset after a stroke or a gradual deterioration with a tumor which causes linguistic
but also other cognitive impairments. On the other side, dementia develops
gradually and is not so easy to distinguish it from normal aging at the beginning.
The area and extent of brain damage determine the type of aphasia and its
symptoms. There is evidence that the demented persons have problems in
connecting cognition and language (Obler & Gjerlow 1999: 102 103).
Cerebrovascular diseases:
These vascular impairments in the brain are well known to have a negative effect
on cerebral blood flow and thus are main reasons for brain damages and
dementia. They can be the cause for occlusive infarcts or encephalic hemorrhage,
each of them affecting the cerebral blood flow massively. Besides others, the
consequences can be a number of cognitive impairments. [T]he older the patient
who develops a cerebrovascular insult, the worst the prognosis (de la Torre 1997:
80 81, 97).
Hypertension:
As many other diseases also hypertension reduces cerebral blood flow, what can
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lead to decreased cerebral oxygen metabolism. Hypertension can also increase
the amyloid and the neurofribrillary tangles who are markers of AD, but also occur
in other neurodegenerative diseases (Blass & Gibson & Hoyer 1997: 111 - 112).
Cerebral stroke:
This means loss of certain brain functions due to a problem in the blood supply to
the brain which can be due to a blockage (e.g. thrombosis) or a leakage of blood.
The consequence concerning speech can be the inability to understand or
formulate speech. There can also be a so-called silent stroke which does not have
any outward symptoms, but still causes damage to the brain so that the risk for a
major stroke in the future is high. A recent study in the US has found out that
people who carried out regular moderate to intense physical exercise where 40 %
less likely to have a si lent stroke (http://psychcentral.com/news/2011/06/10/
moderate-to-heavy-exercise-for-brain-health/26840.html, 16.7.2011).
To sum up we can stress that cerebral blood flow and metabolism tend to
decrease in later adulthood. And the above prognosis the older the patient the
worst the prognosis holds true for all diseases and impairments in old age.
3 Language learning in later adulthood
Elderly persons of today are in many aspects different from those of previous
generations and surely from coming cohorts2 of the future. Future elderly people
will have grown up in the post-industrialized world including all benefits and risk
2 In this context cohort denotes a sample of persons who were [or will be] born in the same period
of time, and who have therefore lived [will live] through similar social influences (Kimerstorfer 2007: 25).
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factors of modern living. An increasing number of the population will benefit from
improvements of preventative medicine and a rising awareness of health factors in
lifestyle. As mentioned before this will lead to longevity of a greater percentage of
the population and consequently to a higher number of active older adults
(Dickson 1997: 51 52). The lifestyle of older persons will no longer be
determined only by its biological age, but rather by their social and financial
situation, their attitudes and their values (Kimerstorfer 2007: 28). Consequently, we
can observe an increasing number of older people returning to part-time or full-
time learning in many parts of the world (Singleton 2004: 213).
On the other hand, certain structural changes in brain and cognitive problems are
inevitable with aging, but the learners gender plays a significant role for the age of
onset. Affected are to some extent the motor and mental ski lls, but what will be
hold steady is the general knowledge as well as the lexicon. But in addition we
have to accept that there is a slight decrease in attention span, in shor t-term
memory and recall speed (Dickson 1997: 52). Studies report reduced accuracy
and slower reaction time in comparison to the younger subjects (Gazzaley &
DEsposito 2007: 73).
Compared to other fields in brain research only a relatively small number of
studies delivers results about second language learning in late age, only since the
1990ies language development in adults becomes a topic of interest (Nippold
2006: 2, de Bot 2009: 425 426, 429). What does occur in brain when we are
learning? Neuroscientists explain it simply as communication of two neurons.
Electrical stimuli in the dendrites and chemical signals (neurotransmitter) in the
synapses transport learning content to and fro the short- and long-term memory
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areas, the motor, visual or acoustic areas. About 100.000 billion neurons are
involved in this immense task. Each neuron is said to be linked with another 5.000
to 10.000 neurons (Sprenger 1999: 2 3, Obler & Gjerlow 1999: 15).
The main regions of brain involved in learning are the occipital lobes for visual
information and the temporal lobes for acoustic processing influencing speech and
memory. Most important for higher learning processes like critical thinking,
problem solving, planning and decision making are the frontal lobes (Sprenger
1999: 42).
3.1 Aging factor
At this point we have to state that the boundary between normal aging and
preclinical disease is not always easy to define. Some researchers argue that
language impairments during Alzheimers disease are simply an exaggeration of
what happens with normal aging (Obler & Gjerlow 1999: 104). But there are a
number of behaviors of demented persons which have never been seen in normal
elders. This would mean that age-associated cognitive decline is not necessarily
the first stage of an inevitable progression to AD [Alzheimers disease] (Hof &
Morrison 2004: 607).
Many researchers have followed Lennebergs theory of the critical period
hypothesis from the 1960ies which means that after the onset of puberty the
capacity for language acquisition declines because the brain loses plasticity after
its organization and lateralization is completed. This means that the left
hemisphere becomes dominant and specialised for all language functions
(Singleton 1995: 31, Obler & Gjerlow 1999: 70 72, Singleton 2004: 130- 131).
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Some studies also argue that the auditory acuity is highest at the age of 10 -14
years. And because the auditory loss starts immediately afterwards this could be
the reason for an endpoint of a critical age for language learning (Singleton 2004:
119 - 120). The consequence is that it becomes more and more difficult for
persons to acquire a second language in adulthood, especially its phonology and
syntax. But Lenneberg himself stated that lexical development may continue
throughout li fetime, and that it is not impossible for adults to learn and speak a
second language, although it requires conscious and labored efforts. (Nippold
2006: 4-5, Kimerstorfer 2007: 5). But already in 1997 Bialystok argued against a
cut-off point and for a continuous decline of language learning abilities (1997: 117).
Since then there has been a long controversial discussion for and against the
postulation of a critical period (Singleton 1995: 31 -36, Berndt 2003,
Herschensohn 2007: 19, Ohly 2007, Kimerstorfer 2007). Mercifully, the language
scientist Steven Pinker argued that adults can learn a second language as long
as they are motivated, receive enough instruction and practice it sufficiently. But
he also makes clear that adults will never be able to speak an L2 without
conscious effort and a marked foreign accent (Singleton 2004: 103, Nippold 2006:
7).
Nevertheless, the proficiency of late learners in L2 also depends on the amount of
exposure to the language, the type and quality of instruction, the motivation and
aptitude of the learner and the frequency of using the new language. For instance,
Singleton (1995: 44 45) reports about very successful subjects of a study group
who reached a native-like level of the L2. After learning English at school their
exposure to the foreign language was highly increased at the university. They were
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almost exclusively taught in English, attended phonetic and pronunciation trainings
and regularly interacted with native speakers of English during international
conferences. These successful L2 learners were highly motivated and received
their goal of becoming perfect speakers of English because of their efforts and
their exposure to the language for a longer time.
After decades of discussions about the critical period, or as it is called later on, the
sensitive period (Singleton 1995: 45, Herschensohn 2007: 11) e.g. in 2003 Berndt
again cites other researchers who also criticize the critical period hypothesis
(2003: 29):
Age does influence language learning, but primarily because it is associated with social, psychological, educational, and other factors that can affect L2 proficiency, not because of any critical period that limits the possibility of
language learning by adults.
What makes us optimistic is that there are examples of late learners who reached
(near-)native proficiency what might either be due to better biological preconditions
in brain or be caused by positive parallel influence by the L1 (Nippold 2006: 9-10).
Studies document an interference of L1 at all linguistic levels when learning a
second language, including phonological as well as semantic levels (Albert &
Obler 1978: 226). The level of L1 proficiency, the knowledge of its grammar and
syntax structure can have a greater influence on further language learning,
especially with elder people, than might be known by now (Singleton 2004: 109).
Besides researcher discuss whether the L2 learner simply uses the set of sounds
his brain has stored or whether a second system of sounds is developed for the
L2, the latter still not being identical to that of a native speaker (Obler & Gjerlow
1999: 126).
Already in 1995 and again in 2004, Singleton stated that in learning a second
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23
language the youngsters are better in the long run, but that there are many
exceptions, and that about 5 % of the elderly language learners master the second
language although they have started learning it long after the critical period (Obler
& Gjerlow 1999: 133, Singleton 2004: 16 - 17). Nevertheless, a number of
researchers agree on the fact that children are better at learning grammar of an L2
language and in gaining a native-like pronunciation (Berndt 2003: 28). An
extraordinary example of late language learning was the author Joseph Conrad,
an immigrant from Poland to Great Britain, who managed to learn the English
language in reading and writing perfectly like a native speaker, but was never able
to speak it properly (Singleton 1995: 30).
Nevertheless, older language learners might be handicapped to a certain extent,
but they can always fill the gap with their life experience. Besides their broad
knowledge in many fields they have trained a series of cognitive strategies and
procedures which in this context can account for better and faster combination of
new learning content to an existing context in the long-term memory of the brain
(Berndt 2003: 137-138).
3.2 Intelligence and aptitude
Intelligence is the ability to deal with cognitive complexity (Gottfredson 1998: 25)
which includes all components of cognitive ability of men. Therefore it is also a
factor in language acquisition, but more in formal language learning and but not so
much in informal, social use of the language. This might change in older learners
who tend to use strategies and learning styles determined by intelligence also in
informal situations of language use (Kimerstorfer 2007; 8). Intelligence is said to
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24
be an indicator for information processing and learning in brain. The Seattle
Longitudinal Study tested individuals every 7 years and found out that even at the
age of 78 the performance during an intelligence test had increased by 8 %
(Berndt 2003: 115- 116).
On the other hand, aptitude is a special competence of person on one or more
areas, usually above-average. Quite often we hear about highly skilled persons
although we can assume that everybody has got more or less talents
(http://de.wikipedia.org/wiki/Begabung, 23.7.2011). Aptitudes which help to
advance language learning could be special analytical skills or a good working
memory (DeKeyser 2007: 227). Aptitude is not a prerequisite for language learning
but it makes learning easier, especially for older persons. But also learners with
less aptitude for language learning can achieve a certain level of proficiency
(Kimerstorfer 2007: 9).
3.3 Education
Concerning education as positive prerequisite for language learning in adulthood it
seems to be proven that a higher than average education can delay the general
cognitive decline by one year for each year of education. And for females the
decline can sometimes be delayed ti ll the age of 70 (Baddeley 1998: 319).
The results of a study in 1999 asking for the factors that influence naming in
adulthood showed significant correlations between naming and education,
professional reading, number of adult education courses and the work-related
language use (Barresi et al 1999: 84 85). The conclusion we can draw from
these results is that adults should engage in active language activities throughout
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25
their life to maintain a good word-finding ability (Barresi et al 1999: 88).
The results of various studies attest that mental activity during lifespan, e.g.
including higher education, reduce the risk of developing dementia. Any mental
activity increases the cerebral blood flow and thus the provision with vital elements
like glucose or oxygen (de la Torre 1997: 90). Generally speaking, the higher the
education of a person the more probable and the more successful he/she will learn
a second language in late adulthood (Berndt 2003: 14).
3.4 Motivation to learn a language
Motivation is certainly an important factor for language learning, especially for the
degree of proficiency being reached. If an adult particularly in older age has no
reason to invest time and money in learning a second language and even more to
learn it to a level of a native
speaker he will never reach
this aim (Nippold 2006: 10,
Kimerstorfer 2007: 11). Motiva-
tion can even make up for de-
ficiencies both in ones lan-
guage aptitude and in learning
condition (Drnyei 2005: 65).
One of the main reasons for a
attending a language course, or
for further training in older age
Figure 4: Attending private courses of 60+ persons in Austria 2008
Source: Statistik Austria, Bildung in Zahlen 2010, p. 115
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26
in general, is to make up for education which had not been possible in younger
age. As we know that the chances for education of the todays 60 years old were
by far not so excellent than they are for young people nowadays, we can
understand that for that generation language learning can be seen a sort of
compensation. The diagram on the previous page confirms these assumptions
showing that for Austrian 60+ students attending courses language learning is
already second after sports, and it is followed by music, art and design, then
comes next self-development, and immediately after that computer training.
Especially women of the mentioned age group are eager to take the chance of
fulfilling perhaps a long wanted wish. Women of older age are also much more
engaged with sports, travelling or cultural and educational activity than men of the
same age (Berndt 2003: 148 149). Furthermore, there are gender-specific
differences in the choice of education. Women seem to prefer language and
literature as well as psychology whereas men rather start with subjects like history,
archaeology or geography (Kimerstorfer 2007: 69).
A further motivation factor is generated by the phenomenon of loss of social
contacts after retirement which can also be a strong motivation for language
learning in a public institution. On the one side, social contacts from the time of
professional life drop away, often because of strongly differing interests. On the
other side, often the family situation has changed: Children are grown up and live
their own lives, sometimes the partner of many years has died. Therefore, the
finding and cultivation of new social contacts is a main factor for attending a
language course or starting a (language) study program at a university. Often it is
important that older persons can leave the house to meet with likeminded contacts
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27
(Berndt 2003: 153).
As said before, language learning in later adulthood is motivated by the wish to
travel to other countries and to be able to communicate with people living there.
Actually, the tourism industry recently has created an increasing number of travel
packages especially designed for the target group of the elderly people, including
educational trips including language course abroad (Sprachurlaub fr Menschen
ab 50). They describe the trips as continuing education without compulsion, in a
relaxing atmosphere. The participants are likeminded and therefore pleasant
social contacts. The described development could be a new field of activity for the
recent occupational field of foreign language geragogy (Berndt 2003: 154 - 155).
3.5 Learning styles
Each learner has a certain learning style according to his type and preconditions.
In literature they list four types of learning: visual learning, auditory learning,
kinaestetic learning, tactile learning types. Some people can learn better when the
content is visualized. This means the learner can read the text or can study it on a
chart. Listening to texts and lexical items again and again can help the auditory
type. The kinaesthetic learner wants to write down the tasks or to draw
connections in a graph (e.g. mindmapping technique), and the tactile learner
learns best by executing tasks like building a model (Kimerstorfer 2007: 10).
Integrative learning can give a very strong impetus for language learning because
it takes place when the learner identifies emotionally with the culture behind the
language he is learning. The learner is interested in the people and the culture, the
history or the nature of the country whose language he is learning. On the other
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28
hand, if learning a certain language only has functional or practical reasons, e.g.
learning for an exam or only for job-related reasons, it is called instrumental
learning. Surely, the pressure to reach a certain proficiency will be high in this
case, but this kind of learning will hardly be relevant for older learners
(Kimerstorfer 2007: 11).
4 Use it or lose it successful language learning as older adult
As we can conclude from the above arguments, the elder generation will be more
and more interested in learning foreign languages in future. Because of the fact
that people become older and die later tertiary (language) education will take place
more and more often in later age. Thus, all the above mentioned consequences
have to be taken into account and a rethinking has to take place. But after all we
must not forget that (foreign or second language) learning can or should take
place during the whole lifetime. The UNESCO World Education Report 2000
stresses in its title that education for all throughout lifetime must be possible
(Berndt 2003: 231).
Concerning the neurolinguistic research in the field of adult language learning, a
number of neuroimaging methods help to study the effects of learning on brain
structures in vivo. Besides morphometric and volumetric techniques, more recently
voxel-based morphometry (VBM) is used to measure changes in grey and white
matter. It can show the effects of learning and language practice on the brain
structure. The results depict the structural differences depending on age of
acquisition of the second language and the proficiency, as well as the number of
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29
languages. But there is still disagreement in interpreting the results of VBM
(Osterhout 2008: 7-8).
Most recent cortical stimulation studies show detailed patterns of cerebral
language activation, especially the differences of localization and organization of
more than one language. PET as well as fMRI techniques are used to find out
whether different languages activate different brain areas by imaging the changes
in neuronal activities. The most interesting aspect of these new technologies is
that all the various areas of the brain being involved in a cognitive task (e.g.
production and perception of a language) can be displayed all at once. And recent
results show that L2 processing involves largely the same language-specific
cortical area as native language (L1) processing (Wattendorf & Festman 2008: 4 -
5).
4.1 Delaying the effects of brain aging
Researchers agree that successful aging consists of three components:
Low probability of disease or disability,
high cognitive and physical function capacity,
active engagement with life (Rowe & Kahn 1999: .434).
Thus, we can derive that learning (a language) is an important factor of successful
aging (Ohly 2007: 87). In the meantime the terms "healthy ageing" or "optimal
ageing" have been proposed as alternative terms to successful aging (Gilmer &
Aldwin 2003: 25). The most valuable findings in brain aging are surely that besides
genetics the lifestyle factors can highly influence the rate of changes in brain
(Guttman 2001: 3). Some keys to longevity including a long-lasting learning ability
can be summarized as follows.
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30
Apart from being active, nutrition is a relevant factor in later age to back up health
and thus preserve mental fitness. As mentioned above the brain needs a number
of neurotransmitters to transport impulses. E.g. acetylcholine is produced from
choline which can be found in eggs, liver or soy products; this chemical substance
helps to build long-term memory. Also carbohydrates are necessary for a healthy
brain because they contain tryptophan which causes the release of serotonin. That
is why we can conclude that it makes sense that each meal during a day includes
carbohydrates and proteins. And as the brain consists of about 78 % water we
should drink enough water or any other liquids (Sprenger 1999: 96).
In Western civilization we eat too much food in general and consume too much
salt and sugar causing high blood pressure and diabetes. Fresh fruits and
vegetables are important for antioxidants like vitamine C and E, as mentioned
above, to avoid damages in brain.
Experts also agree upon the fact that the more active elderly people are, the more
likely they are to stay physically and mentally fit and to be satisfied with life
(http://www.zirh.com/optimal%20aging.aspx, 23.7.2011). Elder adults who maintain
an active lifestyle, namely engaging themselves socially, mentally or physically, are
protected to a certain degree against the onset of dementia, especially Alzheimers
disease, because it avoids accumulation of amyloid and other brain damage. The
most exciting finding in this context is the fact that lifelong bilingualism protects
against the onset of Alzheimers disease. In a recent study the disease was
diagnosed 4.3 years later and even the first symptoms were realized 5.1 years
later than with the monolinguals (Craik & Bialystock & Freedman 2010: 1726).
A series of studies prove that regular physical activity or further working
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31
engagement after retiring helps to sustain a normal level of cerebral blood flow
whereas high blood pressure would cause stroke or heart diseases. Furthermore,
regular mental activity is associated with reduced risk for dementia. Usually,
people with higher education level bear these factors in mind and adapt their
lifestyle accordingly (de la Torre 1997: 89 90).
There are also some tools available to train the brain, i.e. to perform brain
jogging. Besides sporting or artistic activities the older adult can use even video
games for mnemonic training. E.g. a professor from Japan created a game called
Brain Age: Train Your Brain in Minutes a Day! . The Nintendo game includes a
variety of puzzles, stroop tests for training the reaction time, mathematical
questions, and Sudoku puzzles and thus trains cognitive, motor and linguistic
areas in brain (http://de.wikipedia.org/wiki/Dr._Kawashimas_Gehirn-Jogging,
25.7.2011).
Furthermore, people who are happy seem to live longer. People who are more
than averagely successful in life can delay their cognitive decline by three years
(Baddeley 1998: 320). The explanation could be that as when one is happy,
certain chemicals and hormones are produced. For instance, being single can
shorten lifespan whereas having children paradoxically can extend life
(http://www.zirh.com/optimal%20 aging.aspx, 23.7.2011).
As we have to summarize that language learning is not so easy in later adulthood
we should find out some strategies to improve the chance to learn a foreign
language. The teachers as well as the learning environment should be adjusted to
the cognitive capacities of the older brains.
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32
4.2 Prerequisites of language learning
Singleton (2004: 136) describes Lennebergs arguments that language learning in
adulthood is possible despite of his critical period hypothesis because of language
universals. This means that although languages are so different, every language is
based on the same universal principles of semantics, syntax and phonology
(Singleton 2004: 135). In this context Lenneberg states that L1 acquisition
provides a basis for a degree of L2 learning and goes on:
A person can learn to communicate in a foreign language at the age of fourty we may assume that the cerebral organization for language learning as such has taken place during chi ldhood, and since natural languages tend to resemble one another the matrix for language skills is present (Lenneberg 1967 cited in Singleton 2004: 136).
Many researchers disagree with these arguments, but they could be an optimistic
basis for language learning in older age.
Furthermore, an adequate
financial basis is a precondition
for further education in late
adulthood (Berndt 2003: 15).
Adult education centers offer
special programs and a great
number of foreign languages for
elderly persons at favourable
prices. An increasing number of
older people are studying at
universities. But as the diagram shows the launching of tuition fees in Austria in
2000 caused a rapid decrease of the 60+ students so that only 0.93 % of the total
Figure 3: Development of 60+ University students in Austria 1980-2009
Source: Statistik Austria, Bildung in Zahlen 2010, p. 111
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33
number of students was 60 years old or more in the following year.
4.3 Strategies for language learning 60+
Learning strategies are concepts to achieve the learning goal, in this context
namely to reach the goal of a certain proficiency of a (second) language. They will
consist of planned actions from starting onwards and step by step to the aim of
learning a second or foreign language, ideally in using the most apt learning
techniques according to the type of learning of the person, as well as the
information of previous learning experience. These learning strategies are
techniques for improving the learning process (Ohly 2007: 88, Kimerstorfer 2007:
16-17). A good language teacher for older pupils is the one who can incorporate
the students life experience into the learning process (Berndt 2003: 232).
Moreover, as the visual and auditory capacities with elder persons often are
restricted the language trainer has to find teaching techniques which account for
these impairments. The mean hearing loss is about 20 % at the age of 60, 30 %
with 70 years and 43 % at the age of 80. Before that age there had been a linear
decline till the age of 50. This hearing loss is noticeable mainly in the high-
frequency range of sounds. Consequently, mainly consonants with high frequency
sounds cannot be distinguished properly (in German f, s or z) what can lead to
mix-ups. For the teacher or trainer of a language this means that there should not
be much background noise in the teaching room, that linguistic components
should be pronounced clearly and not overlapping (Berndt 2003: 124).
And as the eye lens of a 60 year old has almost lost its elasticity he will have
problems to see objects nearby properly. After the visual acuity peak at the age of
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34
18 it steadily declines till 55. Furthermore, the retina can have lost transparency so
that the eye can spot fewer than 30 % of light intensity. This means that pictures or
presentations of linguistic contents or exercises should be adapted accordingly
(Berndt 2003: 124 126, Singleton 2004: 120 - 121). Consequently, L2 teachers
should be aware of these impairments and calculate a longer time of exposure of
learning tools. Of help for the older learner is the combination of audio and visual
presentations and an increased time for adaption between lighted and darkened
surroundings (Singleton 2004: 121).
As the mentioned visual and auditory impairments can occur earlier or later in late
adulthood and can be stronger or weaker the learning abilities can vary from
person to person. Therefore, individual learning strategies must be adapted
accordingly. If a person has former experience with language learning it wi ll be
easier to teach a new language again. Language learning should not happen
under pressure of time. Complex learning content should be split up into single
teaching modules. Older learners rather concentrate on quality learning and
quantity is no more a priority. In addition, older people cannot concentrate on
content too long and they can be distracted faster from a learning situation. Elder
learners are better in acquiring language modules if they can work them through
with their own speed (Berndt 2003: 140 - 142, 147, Singleton 2004: 121).
Handwriting is a skill we use the whole lifetime and is performed automatically
more or less but studies have proofed that already at the age of 40 this manual
skill is slowing down and till the age of 60 it has decreased heavily. This is caused
by the decrease in reaction time in general but also by a reduced motor
coordination of the fingers at the mentioned stages of age. The central nervous
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35
system is not able any more to deal with too many impulses at the same time.
Teachers are requested to prepare learning material that does not afford too much
writing in a short time (Berndt 2003: 127- 128).
As aging is associated with the slowing down of processing speech, parallel to the
slowing down of all reactions of older adults, the problem seems to lie in the
capacity of the working memory. In other words this means that fewer elements
can be processed in a certain period of time what should be kept in mind by
teachers of elderly people (Baddeley 1998: 302 - 305, Singleton 2004: 214).
Taking these facts into account an example for a language learning lesson with an
older group of pupils could be structured as follows: Warming up repeating
listening to a text reading the text analysis/grammar exercises with new
contents repetition of hearing and listening evaluation (Berndt 2003: 229). In
this context it is important to state that it is helpful to older learners that the lessons
follow a certain structure. But in spite of all these training efforts we have to face
the fact that we cannot give a 70 -year-old the memory of a 20-year-old
(Baddeley 1998: 313).
5 Conclusions and future prospects
Following recent trends we have to be aware that by 2050 the group of the elder
people may exceed that of the younger population. Consequently, the late-in-life
educational opportunities will have to increase. If we further assume that a large
part of the world population will be bi- or multilingual in future it should be
indispensable that research in all the above mentioned sciences should be
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36
increased in the field of aging and language learning.
Concerning foreign language learning in old age we can sum up that almost
native-like proficiency in a second language can be achieved also by elder
learners, when they are immersed in the new language, can use it in many
situations and are highly motivated and want to reach a certain level because of a
certain reason (Nippold 2006: 11). But of course we have to accept that there are
situations where perfectness, almost native-likeness in the new language is not
the main goal. Cognitive or personal circumstances have to be taken into account
and the teaching techniques and learning activities have to be adapted adequately
(Muoz 2007: 248).
Language teachers of older pupils should keep in mind to implement certain basic
technologies: give clear speech input, offer repeated opportunities to hear and
listen and to train new elements, apply memory strategies, divide complex content
in single modules and do not set under too much time pressure (Singleton 2004:
215). Concerning the teaching environment institutions should offer rooms with
ideal illumination and professional acoustics, the atmosphere should be inviting
and stimulating, but in any case adapted to adult pupils. Thus a healthy older adult
learner will become a successful foreign language learner
Language learning is rarely an end in itself. An increasing number of educated
people have realized that it is necessary to train the brain to keep it working. This
activity can start with crossword puzzles and might end in learning a second
language, wherein the former only needs the retrieving of stored information from
the brain but the latter uses complex cognitive processes in the respective brain
regions. And the successful elderly foreign language speaker is proud of his new
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37
knowledge. He likes to communicate with native speakers, to read literary work of
the new language, to use it for further studies or when travelling abroad (Singleton
2004: 219).
Furthermore, to maintain our brains capacity as long as possible a change in
lifestyle will be necessary. Studies proofed that cognitive loss is to a large extent
preventable (Guttman 2001: 4). Consequently, the best advice we can give to
elder people is to keep their mind active and uti lize their memory and cognitive
skills: Use it or lose it is the adage (http://www.zirh.com/ optimal%20aging.aspx,
23.7.2011).
In spite of such a great amount of know how we have gained about adult language
learning and the relevant processes in brain and the strategies we can offer there
still remains a huge need for age-focused (empirical) research concerning L1 as
well as L2 learning. Regarding the future changes in population development
towards a larger percentage of older adults there remain immense challenges for
various sciences, especially health sciences, economics and tertiary education.
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38
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