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Human Mental Abilities

Lecture 7

Leonardo Gabales

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Lecture 7 Cognitive ageing

Cognitive enhancement

The Flynn effect

Exam preparation

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The Stability of Mental Abilities Are mental abilities stable?

Childhood developmental trends Adult developmental trends Clinical cases

Are the relationships between mental abilities stable? Cognitive abilities generally become more

readily differentiable

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Childhood Developmental Trends in Cognitive Abilities Childhood and adolescence are periods

of rapid physical and intellectual change Working memory capacity increases Strategy use becomes more prevalent and

the strategies employed become increasingly sophisticated

A greater ability to handle complex thought The Gf/Gc factors become more readily

differentiable

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Childhood Trends in Cognitive Abilities

(From Halford, Andrews, Dalton, Boag & Zielinski, 2002)

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Adult Developmental Trends in Cognitive Abilities Older adulthood is also a period of

physical and intellectual change Working memory capacity declines Processing speed declines Mental disorders such as Alzheimer’s and

dementia become more prevalent

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Developmental Trends in Intelligence Test Performance How do children and older adults

compare to young adults on intelligence tests? Some good news Some bad news

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The Bad News

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The Bad News Gf, Gv, and Gs all decline in later

adulthood SAR (not shown in the graph) also

declines in later adulthood

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The Good News

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The Good News Gc shows steady gains into later adulthood

People appear to acquire more culturally relevant knowledge

Not really surprising

TSR seems to stabilise in later adulthood People appear to develop broader, more fluent

long-term memory retrieval processes Is this surprising?

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Are Older People Less Intelligent? Intelligence is a latent variable - it cannot be

measured through any single factor The drops in Gf, Gv, Gs, and SAR are largely

cancelled out by the increases in Gc and TSR IQ (when measured by a balanced battery of

tests) appears to be relatively stable People continue to function quite well, although

the way that they function may change

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Implications for Research When examining age related changes in

intelligence it is important to sample from a broad range of abilities If only Gf tests are used, older adults will show

marked decline If only Gc tests are used, older adults will show

marked gains But what is the most popular measure of

intelligence in the literature? The Raven’s Progressive Matrices (Gf)

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So Do We Just Accept These Declines? NO!

Do not go gentle into that good night,

Old age should burn and rave at close of day

Rage, rage against the dying of the light

(Dylan Thomas)

And you thought I couldn’t get a poetry quote in…

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Cognitive Enhancement There is a reluctance to accept age

related decline of any kind Plastic surgery

There is a growing market for cognitive enhancers Cognitive training programs Drugs (nootropics)

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Cognitive Training Programs These tend to vary along two

dimensions What they target

E.g. fluid intelligence specifically vs the systems thought to serve fluid intelligence

The degree of assistance One-on-one tutor guided training vs self-guided

practice

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Cognitive Training Programs These have generally been tested on specific

groups Children (e.g. as a treatment for ADHD) Older adults Clinical patients (e.g. brain injury patients)

In recent years, there has been a strong trend towards computerisation E.g. Brain Age: Train Your Brain in Minutes a Day

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Brain Training… Brought to you by Nintendo Brain Age: Train Your Brain in Minutes

a Day A video game for the Nintendo DS (a

handheld console) Extremely popular ~14 MILLION copies

sold since 2005 Many of these copies have been sold outside of

the stereotypical videogame audience

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Brain Training… Brought to you by Nintendo The idea behind the game is fairly

simple There is an ideal brain age (20 years old) Players complete a range of exercises

each day to first reach, and then maintain the level of performance typical of 20 year olds

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Brain Training… Brought to you by Nintendo The game includes a broad range of

exercises Stroop test Word memory Connect maze Calculations X20 Number cruncher

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Brain Training… Brought to you by Nintendo The Stroop test

Blue Red

Red Yellow

Green Blue

Yellow Green

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Brain Training… Brought to you by Nintendo The connect maze

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Brain Training… Brought to you by Nintendo An interesting fact: virtually all of the

exercises in the game are archetypical cognitive ability measures Stroop - a classic interference task Word memory - a classic STM task Connect maze - a classic PS task Calculations X20 - a classic PS task Number cruncher - a classic WM/PS task

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Brain Training… Brought to you by Nintendo Does the game make you smarter?

Any increase in performance on cognitive ability measures is likely to be very specific and due to having practiced those measures extensively

There are suggestions that cognitive activity (of any kind) can slow down the decline in certain mental abilities

Interestingly, Nintendo makes no claims as to its effectiveness

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Cognitive Training Programs for Older Adults Fluid intelligence is widely considered to

be a key aspect of intelligence, hence much of the effort has focused on improving it in older adults Training older adults on fluid intelligence

tasks Training older adults to increase working

memory capacity

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Cognitive Training Programs for Older Adults A number of studies have looked at

training older adults on specific fluid intelligence tasks Raven’s Progressive Matrices Figural relations Reasoning tasks (of various kinds)

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Training on Fluid Intelligence Tasks Task training usually involves at least one (or

more) of the following: Expert feedback Item level feedback (e.g. which items they got

wrong and why their answers were wrong) Training in task-specific strategy deployment Training in general problem solving techniques

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Training on Fluid Intelligence Tasks Two approaches are common

Tutor-directed feedback Often fairly intense, with detailed individualised feedback

available Self-guided practice

Minimal scaffolding, it is not uncommon for participants to simply be given the items to do on their own

Comparing the two approaches gives researchers a measure of the efficacy of training

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Effects? The findings are often mixed

A few studies have found effects as large as ~1.0 SD

Effects are typically lower (~0.5 SD or less) Increased performance usually does not generalise

very well to other tasks What causes these gains?

Practice? Tutor-directed feedback and self-guided practice often show very similar gains

An increase in strategy deployment An increase in capacity?

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Conclusions It doesn’t look like capacity per se is

being increased… rather existing capacity seems to be used better Increased strategy use Poor generalisation to other tasks

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Training Working Memory Working memory is the system responsible for

Simultaneous processing and storage of information

Attention Executive functioning

All of these are related to reasoning and learning so perhaps increasing WM capacity will increase Gf Correlation between WM and Gf is typically ~0.3-

0.6 (although correlations as high as 0.98 have been found)

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Training Working Memory Again most of the research has been done using

children, older adults and clinical samples Effects are often small (e.g. an increase of 0.4 blocks

on the Corsi blocks task) Effects are often highly specific Effects are often attributable to increased strategy

deployment (and not increased capacity) Effects are often attributable to better sustained

attention Problems with the validity of the outcome measures

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The Flynn Effect How do we stack up against our

predecessors? Is the number of correct responses

required for an IQ score of 100 the same today as it was 50 years ago?

Intuitively, it seems obvious that we couldn’t be too much different from them, otherwise how would they have functioned?

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The Flynn Effect However… there have been massive

increases in the scores required to reach an IQ of 100

These gains have become so famous as to earn their own nickname after James R. Flynn who popularised them If you are interested in this topic I highly

recommend Flynn’s (2007) book

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The Flynn Effect

(From Flynn, 2007)

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The Flynn Effect Generally speaking there are large increases

in test scores across the board… but it gets stranger The LARGEST increases are in measures of Gf

Were our parents incapable of reasoning and on-the-spot problem solving?

The SMALLEST increases are in measures of Gc How have we gotten smarter without knowing more?

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Some Explanations (Flynn, 2007)

Genetic Largely discounted due to the timescales

involved Environmental

Better nutrition has probably helped but it can’t explain the sheer size of the increase

Education Cultural shifts

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Environmental Explanations Scientific thinking vs non-scientific thinking

Education has placed increasing emphasis on the use of abstract categories and the manipulation of abstract variables

Gf measures prize abstract thinking and abstract categorisation

E.g. Similarities On the other hand, the emphasis placed on

culturally relevant knowledge has not changed

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Some Examples

Q: All bears are white where there is always snow; in Novaya Zemlya there is always snow; what colour are the bears there?

A: I have only seen black bears and I do not talk of what I have not seen

(From Flynn, 2007)

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Some Examples Raven’s Progressive Matrices

Difficulty is generally manipulated by Increasing the number of rules that must be used Making the rules more complex

The order of item difficulty corresponds fairly well with Piaget’s stage theory, which moves from concrete to increasingly abstract forms of reasoning

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The Flynn Effect People today are NOT necessarily more

intelligent The style of thinking has changed A greater degree of education The way that items are scored and

generated vastly favours the forms of thinking prevalent today

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The Flynn Effect’s Effects Most research into cognitive ageing is cross-

sectional This means that you compare today’s 20 year olds with

today’s 60 year olds - you do not track 20 year olds for 40 years

Does this explain the “decline” in fluid intelligence? Possibly… older participants may be thinking about the

items in a qualitatively different way However… the declines in working memory and

processing speed do seem real and these systems do serve fluid intelligence

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Summary Cognitive ageing

Not everything declines Cognitive enhancement

Generally limited in effect and fairly task specific The Flynn effect

An environmental explanation incorporating education and changes in styles of thinking seems most plausible

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Exam Preparation Only the lectures and the commentary

that I provided are assessable The supplementary readings are just

that - they are not directly assessable

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What to Study This list is NOT exhaustive, but make sure you

understand The “big three”

Gf/Gc theory Spearman’s g theory Three-stratum theory

Reliability and validity Representative samples and normative testing SB and WAIS Group differences in intelligence Cognitive ageing and the Flynn effect

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Some Words of Acknowledgement A very special thank you to Dr David

Bowman, who took these lectures during Semester 2 of 2007 and was kind enough to provide me with his lecture notes

Thanks also go to my supervisor Dr Damian Birney, for suggesting (strongly) that I put my hand up for lecturing

Finally… a big thanks to all of you for attending these lectures

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A final quote…