Focal Cognitive ImpairmentsStephen A. Ujano

References: Harrison’s Principles of Internal Medicine 18th edBates Guide to Physical Examination and History Taking 11th ed

MEMORY FUNCTION AND AMNESTIC DISORDERS

LANGUAGE APHASIA

a. Wernicke’s Aphasia

b. Broca’s Aphasia

Description Speech is nonfluent, labored, interrupted by many word-finding pauses, and usually dysarthric.

Less function words but rich in substantive nouns and verbsAbnormal word order and inappropriate deployment of bound morphemes- AGRAMMATISMSpeech is telegraphic and pithy but quite informative; reduced to a grunt or single word emitted in different intonationsComprehension deficit for function words and syntaxPatient is aware of the conditionBroca’s area (inferior frontal convolution) and surrounding anterior perisylvian and insular cortex - MOST COMMON LESION SITEInfarction of Broca’s area and occlusion of the superior MCA – MOST COMMON ETIOLOGY

Comprehension Preserved except grammarRepetition ImpairedNaming ImpairedFluency Decreased

Description Comprehension is impaired for spoken and written language,for single words as well as sentencesMany function words but few substantive nouns or verbsLanguage output is fluent but is highly paraphasic and circumlocutious.Strings of neologisms – JARGON APHASIAGestures and pantomime do not improve communication.Patient is unaware of condition (language deficit)Posterior portion of the language network and tends to involve at least parts of Wernicke’s area – MOST COMMON LESION SITEEmbolus to the inferior MCA (posterior temporal or angular branches) – MOST COMMON ETIOLOGY

Comprehension

Impaired

Repetition ImpairedNaming ImpairedFluency Preserved or Increased

c. Global Aphasia

Description Combined dysfunction of Broca’s and Wernicke’s areasSpeech output is nonfluent, and comprehension of spoken language is severely impaired.Naming, repetition, reading, and writing also are impaired.Patient is unaware of the conditionMiddle cerebral artery (left hemisphere)- MOST COMMON LESION SITEStroke – MOST COMMON ETIOLOGY

Comprehension ImpairedRepetition ImpairedNaming ImpairedFluency Decreased

d. Anomic Aphasia

Description Single most common language disturbance seen in head trauma, metabolic encephalopathy, and Alzheimer’s disease . The “minimal dysfunction” syndrome of the language networkArticulation, comprehension, and repetition are intact, but confrontation naming, word finding, and spelling are impairedLess function words but rich in substantive nouns and verbsLanguage output is fluent but paraphasic, circumlocutious, and uninformative.Fluency may be interrupted by word-finding hesitations.Patient is aware of the conditionLesions can be anywhere within the left hemisphere language network including the middle and inferior temporal gyri

Comprehension PreservedRepetition PreservedNaming ImpairedFluency Preserved except for word-finding pauses

APHASIA DYSARTHRIA APHONIA/DYSPHONIADESCRIPTION----CAUSES

Aphasia refers to a disorder in producing or understanding language.

• Dominant cerebralhemisphere (LEFT) lesion

Dysarthria refers to a defect in the muscular control of the speech apparatus (lips, tongue, palate, or pharynx). Words may be nasal, slurred, or indistinct, but the central symbolic aspect of language remains intact.

• Central or peripheral nervous system motor lesions

• Parkinsonism• Cerebellar disease

Aphonia refers to a loss of voice that accompanies disease affecting the larynx or its nerve supply.Dysphonia refers to less severe impairment in the volume, quality, or pitch of the voice. For example, a person may be hoarse or only able to speak in a whisper.

• Laryngitis• Laryngeal tumors• Unilateral vocal

cord paralysis (CN X)

CORTICAL DISORDERS OF VISUAL FUNCTION AND HEMISPATIAL NEGLECT

A. Parietofrontal Network for Spatial Orientation Adaptive orientation to significant events within the extrapersonalspace is subserved by a large-scale network containing three majorcortical components.

1. cingulate cortex provides access to a motivational mapping of the extrapersonal space2. posterior parietal cortex to a sensorimotor representation of salient extrapersonal events3. frontal eye fields to motor strategies for attentional behaviors

Subcortical components of this network include the striatum and the thalamus.

Three behavioral components of neglect: 1. Sensory events (or their mental representations) within the neglected hemispace have a lesser

impact on overall awareness, 2. There is a paucity of exploratory and orienting acts directed toward the neglected hemispace3. The patient behaves as if the neglected hemispace were motivationally devalued.

Model of Spatial CognitionThe right hemisphere directs attention within the entire extrapersonal space, whereas the left

hemisphere directs attention mostly within the contralateral right hemispace

• Large frontoparietallesion in the right hemisphere

Left Hemispatial Neglect

• Degenerative Dementia

Simultanagnosia• inability to integrate visual information

in the center of gaze with more peripheral information

• “misses the forest for the trees.”• Most dramatic component of Balint’s

syndrome• Occipitotemporal Network for Face and

Object Recognition

Associative Prosopagnosia• cannot recognize familiar faces, including, sometimes, the reflection of his or her own face in

the mirror; can extend to the recognition of individual members of larger generic object groups intact perception recognizes voice modality-specific (visual input)

Visual Object Agnosia• When recognition problems become more generalized and extend to the generic identification

of common objects• Unable either to name a visually presented object or to describe its use

Apperceptive agnosia Face and object recognition disorders also can result from the simultanagnosia of Balint’s

syndrome

Alexia• Describes an inability to either read aloud or comprehend single words and simple sentences• A.K.A. Visual aphasia or word blindness. • It is caused by severe damage to the left side of the brain (the occipital and temporal lobes. -

strokenetwork.org• Focal Cognitive Impairment 2

DAILY BASIS

Examples of Long Term Memory

Episodic Memory- Birthday celebrations in the past.- Most favorite place visited.- Most memorable moments in the last 10 years.- Most traumatic experience.

- Schools attended.- Previous jobs.- SSS ID etc.

NOTE: o Responses should be validated by a close relative or significant other.o Testing semantic and procedural memory is usually outside the realm of the generalist, but if deficits in these

systems are suspected, further tests are warranted.

Clinical Testing Mini-Mental Status Examination - Orientation and Three-Word Recall Free Recall Episodic Memory Peformance The participants were asked to learn two lists of 16 short sentences (e.g. ‘lift the pen’). Each sentence was visually

presented on an index card for 8 s. For one of the lists, the participants were asked to enact each presented sentence, whereas no enactment was required for the other list. Each list presentation was immediately followed by administration of a free recall test. These tasks are referred to as free recall of sentences with enactment (SPTB) and without enactment (VTB). The second free recall test was followed by a cued recall test of the nouns presented in each of the two lists. This provided us with two additional measures of episodic memory performance: cued recall for sentences that were initially learned with enactment (SPTCRC) and for sentences initially learned without enactment (VTCRC)

Conclusion: two free recall-based tests of episodic memory function may be useful for detecting individuals at risk of developing dementia 10 years prior to clinical diagnosisBoraxbekk, C.J. et.al. Dement Geriatric Cognitive Disorders Extra. 2015 May-Aug; 5(2): 191–202.

DAILY BASIS

Examples of Short Term Memory

Working Memory- First thing you do every morning upon

waking up- Car you usually drive- Bet among the candidates for

Presidency

- Place visited last Monday and activities done

- Today’s weather

Clinical Testing - More of test of attention

Digit SpanExplain that you would like to test the patient’s ability to concentrate, perhaps adding that this can be difficult when

people are in pain, ill, or feverish. Recite a series of digits, starting with two at a time and speaking each number clearly at a rate of about one per second. Ask the patient to repeat the numbers back to you. If this repetition is accurate, try a series of three numbers, then four, and so on as long as the patient responds correctly. Jot down the numbers as you say them to ensure your own accuracy. If the patient makes a mistake, try once more with another series of the same length. Stop after a second failure in a single series.

When choosing digits, use street numbers, zip codes, telephone numbers, and other numerical sequences that are familiar to you, but avoid consecutive numbers, easily recognized dates, and sequences that are familiar to the patient.

Now, starting again with a series of two, ask the patient to repeat the numbers to you backward. Normal - repeat correctly at least five digits forward and four backward.

Serial 7s

Instruct the patient, “Starting from a hundred, subtract 7, and keep subtracting 7. . . .” Note the effort required and the speed and accuracy of the responses. Writing down the answers helps you keep up with the arithmetic. Normally, a person can complete serial 7s in 1½ minutes, with fewer than four errors. If the patient cannot do serial 7s, try 3s or counting backward.

Spelling BackwardThis can substitute for serial 7s. Say a five-letter word, spell it, for example, W-O-R-L-D, and ask the patient to spell it backward.