Dysexecutive Syndromes

Question 1

Phineas gage

Answer 1

Railway tie sent straight through frontal cortex and he was no longer himself. Prone to anger depressed drinks etc.

Question 2

Disturbances of motor function

Loss of fine movement speed and strength 
Loss of movement programming
Changes in voluntary gaze
Corollary discharge or reafference
Speech problems

Answer 2

Typically after damage to the primary motor cortex

Damage to the premotor or dorsolateral cortex

Damages to frontal eye fields

World will move when looking around

Damage to brocas (agrammatism) damage to supplementary motor cortex (mutism)

Question 3

Deficits in executive function

Convergent vs. Divergent thinking

Loss of behavioural spontaneity

Increased perseveration

Inability to form strategies plan (harder when task is novel)

Loss of response inhibition

Answer 3

Convergent - only one answer
Divergent - asks for a variety of responses to one question

Decreased verbal fluency, design fluency, general behaviours (initiation)

Wisconsin cars sorting task and stroop test

Question 4

Deficits in executive functions contd

Poor temporal memory
Poor working memory
Poor decision making (Iowa gambling task)
- usually after damage to orbitofrontal cortex
Deficits in self regulation
Loss of associative learning (inability to select from competing response)

Answer 4

All on front

Question 5

Deficits in social behaviour

Changes in personality

Answer 5

Pseudo depression

Pseudo psychopathy

Question 6

Frontal subcritical syndromes

Lesions in frontal-subcritical circuits

Dorsolateral
Ventromedial
Orbitofrontal

Answer 6

1. Dysexecutive (impulse control)
2. Pseudodepression
3. Pseudopsychopathy

Question 7

Dorsolateral circuit

Damage results in _______

Answer 7

Executive dysfunction

Poor organizational strategies 
Poor memory search strategies 
Stimulus bound behaviour 
Impaired set shifting and maintenance 
Poor planning 
Poor bottom up executive function or cold

Question 8

Orbitofrontal circuit

Damage results in _________

Answer 8

Impulsivity (disconnects frontal monitoring with the limbic input)

Behavioural disinhibition 
Irritability
Lability 
Euphoria
Inappropriate response to social cues 
Undue familiarity impairment of hot executive function

Question 9

Ventromedial circuit

Damage results in ___________

Answer 9

Apathetic syndrome

Poverty of spontaneous speech 
Indifference to pain
Poor response inhibition 
Reduced creative thought 
Reduced spontaneous behaviour 
Akinetic mutism (don’t move or speak)

Question 10

Diseases affecting the frontal lobe

Schizophrenia

Answer 10

Abnormality in the mesocorrical dopaminergic projection

Decrease in blood flow to the frontal lobes and frontal lobe atrophy

Question 11

Diseases affecting the frontal lobe

Parkinson’s

Answer 11

Loss of dopamine cells in the substantial nigea that project to the prefrontal cortex

Similar to Lewy body dementia

Question 12

Diseases affecting the frontal lobes

Korsakoff’s syndrome

Answer 12

Alcohol induced damage to the dorsomedial thalamus and a deficiency in frontal lobe catecholamines

Question 13

Disorders involving the frontal lobe

TBI

Answer 13

Preferential involvement of anterior regions

Deficits in multiple frontal lobe functions

Question 14

Disorders involving the frontal lobe

ADHD

Answer 14

Disinhibition behaviour

Deficits in executive functions

Question 15

Frontal dementias

Frontotemporal dementia

Answer 15

Formerly ‘picks disease’
3 variants 
A. Behavioural 
B. Primary progressive aphasia 
C. Movement disorders (corticobasal degeneration or progressive supranuclear palsy)

Question 16

Frontal dementias

Lewy body dementia (same system as Parkinson’s)

Answer 16

Changes in movement. 
Changes in behaviour 
     Fluctuating alertness 
     Psychosis (hallucinations) 
Changes in cognitive ability