Chapter 12 Cognitive Control Flashcards
What is the main area of the brain related to cognitive control?
PFC - pre-frontal cortex
Name the specific parts of the brain involved in cognitive control and their function
Lateral PFC
Frontal polar region
Orbital frontal cortex (ventromedial zone)
Medial frontal cortex
Where is the PFC and when does it develop?
The PFC is the area of the frontal lobe from the primary motor cortex forward, encompasses half of the entire frontal lobe; development is late in the process evidenced by me-oriented behaviour of infants and teenagers
The PFC received inputs from and sends inputs to where?
Largest input comes from the thalamus which connects the PFC with subcortical structures including the basal ganglia, cerebellum and various brainstem nuclei
What kind of cognitive deficits are there for someone with frontal lobe damage?
Perseveration, utilization behaviour, goal-oriented behaviour and habits
What is utilization behaviour?
Responding in a prototypical way without regard to context Eg Giving doctor an injection simply because the required elements were there even though it is inappropriate
What are goal oriented actions and habits?
Goal oriented behaviours are based on the assessment of an expected reward or value and the knowledge that there is a causal relationship between the action and the reward; habit is an action that is no longer under the control of a reward, it is stimulus driven`
What kind of memory is affected by frontal lobe damage?
Working memory
Describe the method and results for the monkey with the feeding well experiments (delayed response tasks)
When monkey is shown food being placed in a feeding well and then covering it for a delay period, monkey’s without PFC damage remember where the food is, ones with PFC damage perform poorly; when the wells are covered by a visual cue, both groups of monkey’s perform well. This indicates that associative memory is not affected by PFC damage.
Describe the method and results for the neuronal studies of the delayed response task
When neuronal cells in the PFC are monitored, they show sustained activity during the delay response period but not he cue period; indicates that these cells are involved in working memory
Describe the method and results of the what and where neuron experiments
The firing profiles of PFC neurons were recorded when subjects observed a series of cues differentiated by location and object; this found that specific neurons were fired to when the locations were variable and other neurons were fired when the object was being identified; a third set of neurons were activated during both the “what” and the “where” phase of the task
Describe the method and results of the faces vs scrambled faces task
fMRI recordings were taken while participants were shown a series of faces and scrambled faces and asked to remember the faces, after a delay period they were asked to identify if a probe was part of the memory set; the results found the response rises during the encoding phase and remains high during the retrieval phase in both the PFC and FFA with the FFA peaking earlier in the encoding phase and PFC peaking earlier in the retrieval phase
Describe the method and results of the stroop effect task
When performing the stroop task, interference is demonstrated by response times being slower for the incongruent activity than for the congruent activities; this effect is heightened in participants with PFC damage
Describe the method and results of the dynamic filtering task
Participants are given nouns in two categories; high filtering (multiple verb options) and low filtering (single verb options); and asked to associate verbs to them; activation was found to be higher in the high filtering condition however participants with PFC lesions performed poorly on the high filtering task
Describe the method and results for the task-switching experiment
Participants were asked to say either a letter or number indicated on a square with the cue for which to say indicated by either a colour or a word; patients with PFC lesions showed impairment in the only in the colour cue condition
Describe the method and results of the faces places experiment
Participants were asked to recall either faces or places in a delayed response task; found that the FFA was activated when participants attended to faces and the PPA was suppressed, similarly when asked to attend to places the opposite was found; furthermore, when older participants completed the task suppression was not evident
Describe the Norman and Shallice model of response selection
This model shows that actions are linked to schema control units however the actions can be influenced by the perceptual system, contention scheduling and the supervisory attention system (SAS)
Describe the method, results and theory pertaining to the two choice discrimination task
Error detection hypothesis - Participants were tested on a two-choice letter discrimination task with accelerated responses; errors were made when speed was emphasized and when targets were surrounded by distractors; incorrect responses deviated from correct responses as shown by a large evoked response over the PFC just after the movement is initiated
