AIM LEARNING CYCLE | FINAL YEAR MBBS | KMU CURRICULUM
Student Memory Support
Topic 1: Dementia, Cognitive Decline & Huntington’s Disease
Neuroscience-III | Integrated Medicine & Psychiatry
High-Yield Flashcards • Mnemonics • Memory Tables • Rapid Revision • Clinical Hooks • Exam Essentials
1. High-Yield Flashcards
Tap each question to reveal the answer.
What distinguishes dementia from mild cognitive impairment?
Dementia significantly interferes with independent daily functioning; substantial independence is preserved in mild cognitive impairment.
Which clinical feature most strongly distinguishes delirium from typical dementia progression?
Acute onset with fluctuating attention and awareness suggests delirium.
Which two pathological abnormalities characterize Alzheimer disease?
Extracellular amyloid-beta plaques and intracellular neurofibrillary tangles containing abnormal tau protein.
Why does Alzheimer disease commonly produce early recent memory impairment?
Degeneration of hippocampal and medial temporal memory networks impairs new memory formation.
What clinical and imaging pattern suggests vascular dementia?
Executive dysfunction or slowed thinking with cerebrovascular risk factors and infarcts or small-vessel changes on neuroimaging.
What clinical findings suggest dementia with Lewy bodies?
Fluctuating cognition, recurrent visual hallucinations, spontaneous parkinsonism and REM sleep behaviour disorder.
What early symptoms suggest frontotemporal dementia?
Personality change, disinhibition, loss of empathy or progressive language difficulty, sometimes with relatively preserved early memory.
What three major symptoms suggest normal-pressure hydrocephalus?
Gait disturbance, cognitive decline and urinary urgency or incontinence.
What is the maximum MMSE score, and can it independently diagnose dementia?
30 marks. No; the result requires correlation with clinical history, education and functional assessment.
Name four potentially treatable contributors to cognitive impairment.
Hypothyroidism, vitamin B12 deficiency, depression and anticholinergic medication effects.
What is the mechanism and an important adverse effect of donepezil?
Acetylcholinesterase inhibition increases acetylcholine availability; important adverse effects include bradycardia and gastrointestinal upset.
What is the principal mechanism of memantine?
NMDA receptor antagonism reduces excessive glutamatergic stimulation in Alzheimer disease.
What genetic abnormality causes Huntington’s disease?
Autosomal dominant expansion of CAG repeats in the HTT gene on chromosome 4.
Which brain structures are particularly affected in Huntington’s disease?
The striatum, particularly the caudate nucleus and putamen, causing chorea and frontostriatal dysfunction.
Which drug can reduce Huntington’s chorea, and what important safety issue must be considered?
Tetrabenazine inhibits VMAT2 to suppress chorea; depression and suicide risk must be assessed.
2. Mnemonics
Mnemonic 1 — Common Dementia Patterns
M–V–B–L
Meaning:
- M — Memory: Alzheimer disease
- V — Vascular: Vascular dementia and executive dysfunction
- B — Behaviour: Frontotemporal dementia
- L — Lewy: Fluctuations, visual hallucinations and parkinsonism
Mnemonic 2 — MMSE Main Cognitive Domains
O–R–A–R–L
Meaning:
- O — Orientation: Time and place
- R — Registration: Immediate repetition
- A — Attention: Concentration and calculation
- R — Recall: Delayed memory
- L — Language: Language and constructional tasks
Mnemonic 3 — Huntington’s Major Manifestations
M–P–C
Meaning:
- M — Movement: Chorea and coordination problems
- P — Psychiatric: Depression, irritability and behavioural changes
- C — Cognitive: Executive dysfunction and progressive cognitive decline
3. Memory Tables
Table 1 — Differentiating Important Dementia Types
| Condition | Dominant Feature | Diagnostic Clue |
|---|---|---|
| Alzheimer disease | Recent memory loss | Progressive amnestic decline |
| Vascular dementia | Executive dysfunction | Infarcts and vascular risk factors |
| Lewy body dementia | Fluctuations and hallucinations | Parkinsonism and drug sensitivity |
| Frontotemporal dementia | Behaviour or language impairment | Frontal/anterior temporal atrophy |
Table 2 — Dementia versus Delirium
| Feature | Dementia | Delirium |
|---|---|---|
| Onset | Usually gradual | Acute |
| Course | Often progressive | Fluctuating |
| Attention | May be relatively preserved early | Prominently impaired |
| Clinical priority | Cause assessment and long-term care | Urgent precipitant evaluation |
4. Rapid Revision Points — Last-Minute Revision
Must Remember:
- Dementia requires acquired cognitive decline with impaired independence.
- Mild cognitive impairment preserves substantial functional independence.
- Alzheimer pathology involves amyloid-beta plaques and abnormal tau tangles.
- Vascular cognitive impairment commonly affects executive functioning.
- Lewy body dementia may cause severe antipsychotic sensitivity.
- MMSE is scored out of 30 and does not independently confirm dementia.
- Thyroid dysfunction and vitamin B12 deficiency are treatable contributors.
- Donepezil may cause bradycardia and gastrointestinal adverse effects.
- Memantine is an NMDA receptor antagonist.
- Huntington’s disease is an autosomal dominant HTT CAG-repeat disorder.
5. Clinical Memory Hooks
Clinical Hook 1 — Alzheimer Disease
Repeatedly forgetting recent conversations with progressive functional decline → hippocampal memory-network dysfunction → suspect Alzheimer disease.
Clinical Hook 2 — Lewy Body Dementia
Fluctuating cognition + visual hallucinations + parkinsonism → suspect Lewy body dementia → use particular caution with antipsychotics.
Clinical Hook 3 — Normal-Pressure Hydrocephalus
Gait disturbance + cognitive decline + urinary symptoms → evaluate for normal-pressure hydrocephalus → consider specialist CSF-diversion assessment.
Clinical Hook 4 — Huntington’s Disease
Adult-onset chorea + personality change + affected parent → consider Huntington’s disease → confirm by HTT genetic testing.
6. Starred High-Yield Exam Points
- ⭐ Dementia: Significant cognitive decline plus loss of functional independence.
- ⭐ Alzheimer disease: Amyloid-beta plaques, tau tangles and early episodic memory impairment.
- ⭐ Lewy body dementia: Fluctuating cognition, hallucinations, parkinsonism and neuroleptic sensitivity.
- ⭐ MMSE: Maximum 30 marks; screening results require clinical and functional interpretation.
- ⭐ Cholinesterase inhibitors: Symptomatic cognitive benefit with possible bradycardia.
- ⭐ Huntington’s disease: HTT CAG expansion, autosomal dominant inheritance and striatal degeneration.
- ⭐ Tetrabenazine: VMAT2 inhibition reduces chorea; depression and suicide risk are major cautions.