Neuropsychological testing

The Cognitive Toolkit - Initial Screening Tests

• Purpose: Quickly assess cognitive function when dementia is suspected. Not diagnostic, but guides further workup.

• Common Tools:

  • Mini-Mental State Exam (MMSE):
    • Max score: 30; a score <24 suggests impairment.
    • Assesses orientation, memory, attention, language.
    • Less sensitive for Mild Cognitive Impairment (MCI).
  • Montreal Cognitive Assessment (MoCA):
    • Max score: 30; a score <26 suggests impairment.
    • Better for MCI detection; robustly tests executive & visuospatial skills.
    • Add +1 pt for ≤ 12 yrs education.
  • Mini-Cog:
    • Rapid 3-minute screen combining 3-word recall and a Clock-Drawing Test (CDT).
    • A score of 0-2 out of 5 is a positive screen.

⭐ The MoCA is often preferred for suspected Mild Cognitive Impairment (MCI) as it more robustly evaluates executive function and visuospatial skills compared to the MMSE.

Domain Deep Dive - Probing Specific Functions

• Attention & Concentration
  • Digit Span: Forward (attention) & backward (working memory).
  • Trail Making Test (Part A): Processing speed, visual scanning.
• Executive Function
  • Trail Making Test (Part B): Cognitive flexibility (set-shifting).
  • Wisconsin Card Sorting Test (WCST): Abstract reasoning, strategic planning; sensitive to frontal lobe dysfunction.
  • Stroop Test: Cognitive inhibition, selective attention.
• Memory
  • Wechsler Memory Scale (WMS): Comprehensive battery for verbal/visual memory (immediate & delayed recall).
  • California Verbal Learning Test (CVLT): Word list learning and recall.
• Language
  • Boston Naming Test: Assesses for anomia (word-finding difficulty).
  • Verbal Fluency (FAS/Animals): Spontaneous language production.
• Visuospatial & Constructional
  • Clock-Drawing Test: Rapid screen for constructional apraxia.
  • Block Design (WAIS subtest): Non-verbal problem-solving, spatial analysis.

⭐ The Clock-Drawing Test is a rapid screen assessing visuospatial skills, executive function (planning), and semantic memory. A score < 3 on some scales suggests significant impairment.

Pattern Analysis - Connecting Scores to Syndromes

• Alzheimer's Disease (AD):

  • Primary deficit: Amnesia, specifically poor learning & delayed recall (episodic memory).
  • Visuospatial skills (e.g., clock drawing) & executive function decline later.
  • Verbal fluency is often impaired.

• Vascular Dementia (VaD):

  • Hallmark: Executive dysfunction (e.g., planning, organization) and slowed processing speed.
  • Memory retrieval deficits are common, but recognition is often better than in AD.
  • "Patchy" or "subcortical" pattern of deficits.

• Lewy Body Dementia (LBD):

  • Prominent deficits in attention and visuospatial/executive functions.
  • Memory impairment is less severe than in AD initially.

  • ⭐ Pronounced fluctuations in cognitive performance are a core diagnostic feature, often varying day-to-day or even hour-to-hour.

• Frontotemporal Dementia (FTD):

  • Behavioral Variant (bvFTD): Early, severe executive dysfunction with disinhibition and apathy. Memory is relatively spared.
  • Primary Progressive Aphasia (PPA): Specific language deficits (naming, grammar, comprehension).

High‑Yield Points - ⚡ Biggest Takeaways

• The MMSE is a common screening tool, but it's insensitive to mild cognitive impairment (MCI) and affected by education.
• MoCA has higher sensitivity than MMSE for detecting MCI and early dementia.
• The Clock-Drawing Test quickly screens for visuospatial ability and executive function.
• Verbal fluency tests assess executive function and semantic memory.
• Formal neuropsychological testing is the gold standard for detailed cognitive profiling, essential for ambiguous diagnoses.