L11 Flashcards
what part of the brain allows us to indulge in abstract thought
the frontal cortex
do humans have the biggest brain (when they are all on the same scale)
no
elefinits and whales have bigger brains
what did suzana herculano houzel do
She took a brain and dissolved out all the tissue that isn’t neurons meaning that the neurons are homogenised (floating in the brain sopu)
You then take out a small amount of fluid and count the neurons which by average gives a good estimate of how many neurons are in the brain
she also found that there were different ways for neurons to be packed into the brain
why did suzana herculano houzel want to know the number of neurons in the brain
because of they hypothesis of the more neurons = cognitive ability
does brain mass predict the number of neurons
no
The weight if the brain and the number of neurons does not have a strong relationship
Size of the brain doesn’t relate to the number of neurons
what do you find when comparing primate brains to rodent brains of the same size
although rodent and primate brain were the same size/weight the primate brains always contained a larger number of neurons
what is the relationship between brain size and the cerebral cortex
the bigger the brain the more neurons in the cerebral cortex
primates have significantly more neurons in the cerebral cortex compared to other parts of the brain
what does damage to the prefrountal cortex result in
Patients with prefrontal damage may have severe defects in
decision making and emotional regulation but often have a
remarkable absence of intellectual impairment, as measured by
conventional IQ tests such as the WAIS/WAIS-R.
This enigma might be explained by shortcomings in the tests, which tend to emphasize measures of “crystallized” (e.g.,
vocabulary, fund of information) more than “fluid” (e.g., novel
problem solving) intelligence.
what is crystallised intelligence
previously acquired knowledge and skills ‘crystallized’ with
experience
what is fluid intelligence
the ability to reason and solve problems using new information
without relying on previously acquired knowledge and skills.
what does raven’s progressive matrices test for
it is a test for fluid intelligence
what is raven’s progressive matrices
it is test of non-verbal reasoning
there are 5 shapes and you need to choose the 6th shape to match the pattern
sometimes people with prefrontal cortex damage can still complete this test
what is abstract thought
Abstract thought: Using concepts to make and understand generalizations. Thought where concepts are not tied directly to specific experiences
Examples of abstract concepts include ideas such as:
•Humor
•Imagination
•Social rules
Abstract rules are tested for in what tests
WCST
DNMS
what are concrete rules
describe simple spatio-temporal links between objects: A
red light means stop (stimulus-response or stimulus - outcome) e.g. WCST first block
eg red light means stop
what are abstract rules
they are complex and applicable to multiple exemplars
e.g. DNMS
Unlike concrete rules, abstract rules describe interactive and causal associations between objects, events and
responses. Thus, abstract rules can evoke completely
different responses to the same stimulus exemplar depending on the goal and context. e.g. WCST second block
how is the parin organised
The brain is organised in terms of how vs what
How you interact with those objects is associated with the dorsal stream
Prefrontal cortex is organised in this way as well therefore in the dorsal regions it is how and in the ventral is what. Also the more anterior you go is for the more abstract. And medial is emotional.
This is just theoretical
prefrontal lesions inhibit the ability to organise behaviour
give an example of this
when given a list the controls will compleate the tasks in an order that is efficient and makes sense
prefrontal lesions wont do this. they wont be able to break down the tasks in a semantic way
what does cognitive control during goal planning and execution involve
Identifying primary goal and sub-goals
Retrieval and selection of relevant information
Simultaneously maintaining multiple subgoals
Determine what is required to achieve goals
anticipating consequences
what is the central executive
it is part of the model of working memory
this controls the phonological loop (language), visuospatial sketchpad (visual semantics), and episodic buffer (short term episodic memory)
it acts as a dynamic filter which allows you to select the best option. the prefrontal cortex plays a role in this
what is the role of the dorsolateral PFC
The role of dorsolateral PFC is to define a set of responses suitable for a particular task and then biasing these for selection ‘sculpting the response space’ (Frith)
what is the relationship between cognitive control and creativity
If you want to be more creative then you need to shut down prefrontal cortex
this is because the removal of the DLPFC my free up the response space
what is an example of prefrontal lesions having an effect on creativity
in the matchstick task for the easy level there was no difference
medium the controls preformed better
but the hardest the lesioned group preformed better. this was because the solution followed a different rule to the other levels
what are the cognitive impairments of frontal lobe syndrome
Deficits in temporal ordering, goal directed behaviour and abstract
reasoning. Poor decision-making
(“dysexecutive syndrome”)
what are the emotional changes of frontal lobe syndrome
Apathy, anergia, socially inappropriate outbursts
what are the behavioural deficits of frontal lobe syndrome
Utilization behaviour, perseveration, environmental dependency, socially
inappropriate behaviour, risky behaviour
