25 - Cellular Basis of Behavioural Illness

Question 1

Catatonia 
1
2
3
4
5

Answer 1

• Motor immobility as evidenced by catalepsy (including waxy flexibility) or stupor
• Excessive motor activity (purposeless, not influenced by external stimuli)
• Extreme negativism (motiveless resistance to all instructions or maintenance of a rigid posture against attempts to be moved) or mutism
• Peculiarities of voluntary movement as evidenced by posturing, stereotyped movements, prominent mannerisms, or prominent grimacing
• Echolalia or echopraxia

Question 2

Proportion of adult basal metabolic rate given to brain

Answer 2

~25%

Question 3

Changes in neuronal morphology in schizophrenia

Answer 3

Decreased neuronal size, decreased neuronal connections, decreased dendrites and synapses, decreased connections between thalamus and cortex.

Altered cytoskeleton

Question 4

Metabolite for neuronal energy supplied by astrocytes

Answer 4

Lactate

Question 5

Glial changes in psychiatric disorders

Answer 5

Astrocyte changes.

Evidence of long-term inflammation (from microglia - elevated calprotectin levels).

Question 6

Link between OCD and microglia

Answer 6

HoxB8 is expressed only in microglia.
HoxB8 mutants show similar behaviour to those with OCD (mouse models).
Can be rescued with bone marrow transplant with normal HoxB8 gene.