week 6 - executive functions Flashcards

Question

petrides' 2000: theory of working memory task monkey study

Answer 1

monkey studies with task similar to self ordering pointing show that dorsolateral PFC is particularly important for updating (1995)

Answer 2

frith (2000) - left DLPFC may be responsible for selecting a range of plausible responses - "sculpting the response space" / task setting Frith et al. (1991) - left DLPFC active in "free will" - choosing which finger to move or which word to say vs. being told to do TMS over left DLPFC distrupts random digit generation (jahanshaji et al. 1998) - suggesting that it is functionally different to other areas in the PFC

Answer 3

N-back task (Is this the same image as 'n' before, N is how many images are before) Right DLPFC activity increased for the 3-back and 2-back conditions compared with the 1-back and 0-back conditions the conditions are thought to require more monitoring (but could also be updating)

Answer 4

may be important in monitoring and sustaining attention both for externally presented information (perception tasks) and internally generated information (memory tasks) - 2003 activity greatest in conditions of uncertainty - tip-of-tounges states, confidence judgments in memory (low confidence = greater activity)

Answer 5

left hemisphere: retrieval and maintenance of semantic and/or linguistic information right hemisphere: retrieval and maintenance of visual and/or spatial information

Answer 6

left hemisphere: selecting a possible range of responses and suppressing inappropriate ones; manipulating the contents of working memory right hemisphere: monitoring and checking of information held in mind, particularly in conditions of uncertainty; vigilance and sustained attention

Answer 7

left + right hemispheres multi-tasking; maintaining future intentions / goals while currently performing other tasks or sub-goals

Answer 8

monitoring in situations of response conflict and error detection

Answer 9

unitary accounts argue that there are no 'executive functions' just one general underlying function - one function

Answer 10

patients' performance on many tests of executive function are correlated with each other and with fluid intelligence (2010) - if good at one good at all - Perhaps this is the underlying concept that supports these sorts of separate functions

Answer 11

single-cell recordings of PFC neurons in monkeys show that they change their responsiveness flexibilty according to task demands (2002) so any part of PFC may be able to do any 'executive function' given the right circumstances - So not separate Sometimes neurons for one executive function,, sometimes for another Depending on task * Brain selects whichever parts of PFC most useful to solve task in front of you

Answer 12

duncan and owen (2000) Did a review of where the focal activity was across a wide range of functional neuroimaging studies that involved difficult tasks. Essentially finding where the most activity is (the overlaps) evidence for a single set of fronto-parietal regions called the multiple demand network that is active during all tasks that we consider to involve executive functions - Network of brain regions across the frontal lobe and parietal which is always active across tasks we consider to require executive functions 2017: multiple demand network divides complex tasks into a sequence of "attentional episodes" ie. the ability to break down a complex task into smaller less complex segments (tower of london tasks)

Answer 13

woolgar 2018 80 patients with focal, adult-onset brain lesions patients with more of their lesions with in the MD system showed a greater deficit in fluid intelligence (reasoning) this relationship didnt exist for lesions within th elanguage network thereofre, MD is needed for complex thought - also language is not necessary for complex thought

Answer 14

woolgar 2018 For each patient worked out how much of their brain injury overlapped with the multiple demand network Did they same thing with the language network * These are on the x axis Postmorbid change in fluid intelligence This I show much their scores on Intelligence tests have changed between before and after their injury * Y axis

Answer 15

Challenge in neuropsychology in not having baseline measures * Guess work Calculate the likely change Intelligence tests are challenging Possible to get better at intelligence tests So not relevant to underlying ability Bias across race ect. How do we define intelligence

Answer 16

Damage to language doesn’t seem to effect performance * Language not necessary for complex thoughts

Answer 17

...allow you to complete a complex task

Answer 18

yes or maybe they are you (the voice in your head)

Answer 19

.. prefrontal cortex

Answer 20

possible that there are not different types of executive function, but just one underlying high level ability of healthy humans: to break down a complex task into manageable parts and perform each in order --> possibly the same as fluid intelligence