Inhibitory Control Flashcards
what are the 3 components of inhibitory control?
- IC of attention (selective attention): controlling what we pay attention to
- Cognitive inhibition: inhibiting thoughts and memories
- Response inhibition (self control): inhibiting motor response
Unilateral prefrontal lesions and IC of attention
- measured brain wave activity of PFC patients while they were processing different sights and sounds
- compared to the controls, they had significantly higher sensory signals in the back part of the brain
- demonstrates impaired filtering process
- result in poorer filtering, increased demands on
sensory processing, and increased distractibility
Inhibitory control performance and WM performance Test
- showed faces, scenes, and overlap conditions
- in overlap conditions they asked them to focus on either the face or the scene
Inhibitory control performance and WM performance Test: behavioural results
- significantly reduced accuracy in overlap conditions
- significantly higher reaction time for overlap conditions
- shows effect of distraction
Inhibitory control performance and WM performance Test: imaging results
- looked at P1 amplitude (EEG brain wave)
- sensitive to sensory processing and size of wave can be modulated by attention
- better you are able to boost P1 activity, the more accurate you are on the task
Inhibitory control performance and WM performance Test: Effect of brain stimulation
- used transcranial magnetic stimulation (TMS)
- identified the IFJ, part of PFC involved in attentional control
- when you try to turn off this brain area, WM accuracy declines
- more we amplify the P1 signal, more WM accuracy improves
task switching
requires inhibition of a previous thought set to engage a new, currently appropriate thought set
- Can be quantified as switch cost:time to switch tasks
what brain areas have been associated with cognitive inhibition and task switching?
- right PFC
- damage to right VLPFC has been associated with larger switch costs
proactive interference
old information hinders recall of new information
retroactive inhibition
new information hinders recall of old information
conscious memory suppression
- can use Think/No think paradigm
- study pairs of words and asked to either remember or forget the pairing
- then there is memory test
- when told to forget, they remember less
- increased activity in PFC during suppression, decrease in hippocampal activity (region involved in memories)
- right PFC is doing the forgetting
What tasks are frequently used to measure response inhibition?
- Go no-go
- Stop signal tasks
Go No-Go
- objects are associated with GO and NO GO commands
ex. everytime you see a heart, press button
see a circle, don’t press - most trials are GO, get used to pressing button
- makes NO GO more difficult
- in correct performance, there is significant activation in the right PFC
Stop Signal Tasks
- more difficult
GO trials: - dot starts in circle
- go signal is the dot moving
- have to move circle to new dot location
STOP trials: - dot in middle of circle goes to new spot
- some point after go signal, sound plays (stop signal)
- don’t respond if you hear stop signal
- difficult because you have to stop a behaviour that has already started
Right PFC damage and stop signal task
more damage = longer stop signal reaction time (longer it takes to stop a started action)
