Organic Mental Disorders

Question 1

Definition of organic mental disorders?

Answer 1

Mental disorders that are “due to common, demonstrable aetiology in cerebral diseases, brain injury, or other insult leading to cerebral dysfunction”

Need to be acquired

Can be primary or secondary:
Primary- direct effect on the brain
Secondary- systemic diseases that affect the brain in the addition to other systems/ organs.

Question 2

Common features of organic mental disorders

Answer 2

Cognitive:
Memory, intellect, learning
Sensorium:
Consciousness, attention 
Mood:
Depression, elation, anxiety 
Psychotic:
Hallucinations, delusions
Onset:
Any age, 
Most start in adult life

Question 3

Acute causes of organic mental disorders?

Answer 3

Delirium,
Organic mood disorder,
Organic psychotic disorder

Question 4

Chronic organic mental disorders

Answer 4

Dementia,
Amnesic syndrome,
Organic personality disorder

Question 5

What is delirium

Answer 5

An aetiological LH non specific syndrome characterised by concurrent disturbances of consciousness and attention, perception, thinking, memory, psychomotor behaviour, emotion and sleep-wake cycle

Question 6

Presenting features of delirium?

Answer 6

Impairment of consciousness and attention, 
Global disturbance of cognition,
Psychomotor disturbances, 
Disturbance of sleep-wake cycle,
Emotional disturbance,
Rapid onset,
Diurnally fluctuating,
Duration less than 6 months, 
Physical signs- autonomic activation- tachycardia, hypertension, diaphoresis, dilated pupil, fever 
Dysgraphia

Question 7

Mechanism of delirium

Answer 7

GABAergic and cholinergic neurotransmitter ?
Central cholinergic deficiency ?
Increased dopaminergic activity ?
Direct neurotoxic effect of inflammatory cytokines

Question 8

Delirium management

Answer 8

Treat underlying cause,
Environmental and supportive measures (education, make environment safe, optimise stimulation, orientation)
Medications (antipsychotics, benzodiazepines, promethazine)

Question 9

Symptoms seen in hepatic encephalopathy

Answer 9

General psychomotor retardation,
Drowsiness,
Fluctuating confusion,
Asterixis

Question 10

What is amnesic syndrome?

Answer 10

Syndrome of impairment of recent and remote memory,
Immediate recall preserved,
New learning reduced,
Anterograde and retrograde (may lessen over time) amnesia,
Disorientation in time,
Confabulation,
Perception and other cognitive functions preserved

Question 11

Diencephalic damage that can cause amnesic syndrome?

Answer 11

Korsakoff’s syndrome,
3rd ventricle tumours and cysts,
Bilateral thalamic infarction,
Post subarachnoid haemorrhage,

Especially from anterior communication artery aneurysms

Question 12

Hippocamal damage that causes amnesic syndrome

Answer 12

HSV encephalitis, 
Anoxia, 
Surgical removal of temporal lobes,
Bilateral posterior cerebral artery occlusion,
Closed head injury, 
Early Alzheimer’s disease