COGNITIVE TESTING AND LOCALIZATION MADE RIDICULOUSLY SIMPLE David F. Tang-Wai MDCM FRCPC Assistant Professor (Neurology & Geriatric Medicine), University of Toronto Geriatric Refresher Day, University of Western Ontario, London ON May 2, 2012 Cognitive Testing & Localization 1 1. Cognitive testing involved examination of the various cognitive domains Cognitive domains as examined on the Mini-Mental Status Examination (MMSE) and the Montreal Cognitive Assessment (MoCA) Cognitive Domain MMSE MoCA Orientation Yes Yes Memory - Learning/Delayed recall Yes Yes Attention Yes Yes Language Yes Yes Visuospatial Yes Yes Executive Function Yes Yes Neuropsychological testing involves detailed assessments of each cognitive domain Cognitive Domain Examples of Specific Neuropsychological Tests Orientation Memory - Learning/Delayed recall Attention Language Visuospatial Executive Function Logical (story) memory, California adult verbal learning test (CVLT), Free-cued recall Reverse digit span, letter cancellation Boston Naming Test, Token Test (comprehension) Rey-O complex figure, block design Wisconsin card sorting, Stroop, Trails Making Test
2. Each cognitive domain can be localized to a specific lobe in the brain Cognitive Testing & Localization 2 Executive Function Memory Language Visuospatial Arithmetic Praxis Facial Recognition Lobe in brain Frontal Temporal Left Hemisphere Biparietal & occipial lobes Left Parietal Left parietal Right temporal Sample tests that can examine domain Modified Trails B Digit span WORLD/serial 7s Verbal fluency Letter cancelation Orientation Learning & delayed recall Reading Writing Naming Comprehension Repetition Semantic fluency Cube copy Pentagons copy Calculations (simple arithmetic) Ask patient to show how to... Identify famous faces 3. Localization can be further refined to a specific area within a lobe of the brain Memory Reading, writing, arithmetic Facial recognition Ideomotor praxis Lobe Temporal Left parietal Right temporal Left parietal lobe Where in lobe Hippocampus & Papez circuit Angular & supramarginal gyrus Inferior fusiform & lingual gyrus Inferior parietal lobule Disorders to consider if first presenting symptom Alzheimer s dementia Alzheimer s dementia (posterior cortical atrophy) Frontotemporal dementia - right temporal variant Corticobasal syndrome
Cognitive Testing & Localization 3 Memory Reading, writing, arithmetic Facial recognition Ideomotor praxis Language Localization (left hemisphere) Repetition Comprehension Fluency Naming Writing Lobe Left perisylvian area Left parietal/temporal Spontaneous speech - Left frontal lobe Left temporal Left parietal (see previous) Letter fluency (green) Semantic fluency (red)
Frontal lobe syndromes Dorsolateral Orbitofrontal Anterior Cingulate Cognitive Testing & Localization 4 Function Poor organizational strategies, problem solving, planning, shifting and maintaining sets, verbal working memory, and reduced verbal fluency Personality change: tactlessness, obsessive compulsive disorder; decreased empathy, socially inappropriate behavior; impulsive behavior; inappropriate jocular affect; emotional lability; poor judgment & insight; distractibility; increased sweets Apathy, little display of emotions, decreased motivated behavior/ creative thought, failure of response initiation/suppression, poor response inhibition; lack of concern of personal hygiene, appearing unkempt 4. Guidelines to interpret cognitive testing - determining patterns 1.1. Look at the affected cognitive domains in addition to the total score - this will help determine the pattern of impairment and localization within the brain 1.2. Recall where the cognitive domains are localized within the brain Executive function Memory Language Visuospatial Localization Frontal lobe Temporal lobe (hippocampus/ Papez circuit) Left hemiphere Mainly right temporoparietal lobes 1.3. Common patterns seen on cognitive testing and representative dementing disorders
Cognitive Testing & Localization 5 Problems Seen on Testing Pattern Suggestive Of Examples of Disorders Orientation Delayed word recall Attention 3-step command Learning (many trials) Trials B (MoCA) Letter fluency Intersecting pentagons Necker cube Naming Semantic fluency Writing Comprehension Amnestic Executive dysfunction Frontosubcortical Visuospatial Aphasia Amnestic mild cognitive impairment Alzheimer s dementia Vascular cognitive impairment Parkinson s disease Dementia with Lewy bodies Posterior cortical atrophy Alzheimer s dementia Dementia with Lewy bodies Primary progressive aphasia Semantic dementia Normal cognitive testing but change in behaviour Disinhibition or apathy behaviour Behavioural variant frontotemporal dementia 1.4. In addition to the clinical history and the pattern of cognitive testing, a diagnosis can be made Sample Cases Cognitive Testing Result Diagnosis Case 1: 58 year-old man with 2 year history of progressive memory loss and impairment with his instrumental activities of daily living Case 2: 88 year-old woman with 5 year history of progressive memory impairment, getting lost, unable to cook and balance the finances. No cerebrovascular risk factors or history of stroke. MMSE = 22/30 Orientation 7/10; Learning 3/3 in 1 trial; Attention 5/5; Recall 0/3; Language 8/8; Pentagon copy 1/1 MMSE = 18/30 Orientation 7/10; Learning 3/3 in 2 trials; Attention 2/5 (WORLD); Recall 0/3; Language 6/8; Pentagon copy 0/1 Alzheimer s dementia Cognitive testing revealed a primary amnestic pattern. Given the history of anterograde memory impairment with functional impairment, the clinical scenario is one of Alzheimer s dementia. Alzheimer s dementia - severe Cognitive testing revealed deficits in multiple domains. Given the history of anterograde memory impairment and other cognitive impairments associated with functional impairment, the clinical scenario is one of a moderate-to-severe Alzheimer s dementia.
Sample Cases Cognitive Testing Result Diagnosis Cognitive Testing & Localization 6 Case 3: 56 year-old with 5 year history of progressive apathy, emotional blunting, mental rigidity and dismissed from his job for slacking off Case 4: 74 year-old woman presenting with visual hallucinations, slowness in thought, shuffling gait, and memory problems of 1 year in duration Case 5: 78 year-old math teacher with known Alzheimer s disease presents with acute confusion. MMSE = 30/30 MMSE = 25/30 Orientation 10/10; Learning 3/3 in 5 trials; Attention 3/5 (WORLD); Recall 3/3; Language 8/8; Pentagon copy 0/1 Previous MMSE 26/30 days prior to ictus Orientation 9/10; Learning 3/3 in 1 trials; Attention 5/5 (serial 7 s); Recall 0/3; Language 8/8; Pentagon copy 1/1 MMSE on admission = 20/30 Orientation 9/10; Learning 3/3 in 1 trials; Attention 0/5 (serial 7 s); Recall 0/3; Language 8/8; Pentagon copy 0/1 Frontotemporal dementia - behavioural variant Cognitive screening was normal. The clinical history is primarily a change in personality and behaviour and is associated with an impairment with his iadls (work). In FTD, especially the behavioural and executive dysfunction presentations, the cognitive testing can be normal or mildly impaired early in the disease. Dementia with Lewy Bodies Cognitive testing revealed intact memory but difficulties with attention/executive function (WORLD), frontosubcortical slowing (excess number of trials to learn 3 words), and visuospatial dysfunction. With the history of parkinsonism, visual hallucinations and some cognitive impairment, the clinical scenario is consistent with DLB. Acute left parietal stroke Repeat cognitive testing revealed sudden decline with visuospatial and serial 7s (a crude measure of calculations). These functions localize to the left parietal lobe. Given the sudden change, this man had a stroke in the same area.
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