Frontal Lobes / Executive Functioning / Consciousness

Question 1

executive functions and the control of action in frontal lobes

Answer 1

• Planning and control
  
  • goal-directed behavior: Intentional behavior
  • directed by internal goals (not dictated by environment)
  • Evaluation of action consequences
• Problem solving
  
  • Abstract represenations of problem space
  • Understanding goal structure and action schemes
• Attentional processes, Working memory & central executive functions
  
  • Assigning attentional resources to different aspects of environment
  • assigning working memory resources between cognitive systems

Question 2

incentive motivation

Answer 2

• Determining whether the rewards for behavior are sufficient to warrant the associated costs or risks involved
  
  • Maintaining & updating representations
  • linking cues to incentive properties of outcomes
  • Guiding responses based on value of expected rewards
• When engaged in “gambling”-type tasks, frontal lobes control maintenance of risks and outcome predictions

Question 3

Iowa Gambling Task
fMRI activation

Answer 3

• Patients with Frontal Lobe damage persist with bad decks
• Why gambling?
  
  • These behaviors may relate back to evolutionary cost-benefit of foraging, hunting stealing, attempts to mate, challenging rivals etc.
  • Involve combinations of Executive function and emotional content
  • Stimulates the dopamine reward system

Question 4

impulse control and inhibition

Answer 4

• Inhibitory control over environmentally cued events
• Ability to switch criteria and inhibit pre-potent response (e.g., response inhibition in Wisconsin card sort)
• Adele Diamond suggests that Piagetian tasks (A not B) involve maturation of frontal lobes
  
  • Infants with PKU show later development of frontal lobes and are delayed on A not B task

Question 5

orbitofrontal cortex and social-emotional executive control

Answer 5

Neuroanatomical relationships:

• Basal ganglia loop
• Projections to: amygdala, hippocampus, inferior temporal cortex, DLPFC

Question 6

Damage to Orbitofrontal Cortex

Answer 6

• Disinhibition of socially inappropriate behavior (e.g., peeing in church)
• Difficulty in suppressing responses to irrelevant stimuli
• Example: Phineas Gage (1868)
  
  • “…But because his personality had changed so much, the contractors who had employed him would not give him his place again…He was now fitful, irreverent, and grossly profane, showing little deference for his fellows. He was also impatient and obstinate, yet capricious and vacillating, unable to settle on any of the plans he devised for future action.”