4 - BIOLOGICAL BASIS OF LEARNING

Question 1

how can practice affect intrinsic behaviours?

Answer 1

• brains are not strictly hardwired
• neuroplasticity - very little is hardwired in our brain
• experience changes brain structures at the cellular level - modified by learning

Question 2

define instinct

Answer 2

evolved, species-specific adaptation of behaviour towards the environment

eg rat specific sexual behaviour

Question 3

define learning

Answer 3

rapid, intra-individual adaptation of ones behaviour towards the environment

Question 4

define memory

Answer 4

lasting effects of learning

Question 5

role of cortex in memory (old view)

lashleys experiments on rats

Answer 5

• train rats to navigate maze - make errors at first but then learn fastest way to get to food
• remove part of cortex
• more cortex removed = the worse the performance
• doesn’t matter which part removed - volume is what matters
• if presented with a graph - it should be a diagonal if referring to errors:cortex removed
• if graph shows other brain areas, then not all bars will show an effect

Question 6

lashleys laws

mass action

Answer 6

= learning and memory are a function of intact cortex mass - more tissue, more learning and memory

Question 7

lashleys laws

equipotentiality

Answer 7

= each part of the cortex is equally involved in learning and memory

Question 8

what are lashleys laws?

2 things

Answer 8

mass action and equipotentiality

Question 9

what made lashley wrong?

Answer 9

• there are brain structures involved specifically with learning and memory but they are mostly sub-cortical
• information from lesion studies
• deliberate lesions in animals
• patients with brain lesions (cannot compare against baseline so cannot assess change) (also not as ethical and damage won’t be deliberate)

Question 10

which limbic structures are involved in factual and relational (relations in space and emotion) learning?

(3 structures)

Answer 10

hippocampus

amygdala

mammillary bodies

Question 11

which structures are involved in motor skill learning?

Answer 11

cerebellum

basal ganglia

Question 12

input into the hippocampus

subcortical = 2 / cortical = 2

Answer 12

subcortical =

• amygdala (fear and aggression)
• septal nuclei (‘pleasure centre’)

cortical =

• limbic system (aka cingulate cortex)(emotional evaluation of things)(just above corpus callosum)
• ALL association areas (cognitive evaluation) converge on the hippocampus

(high-level cognitive processing, inter sensory integration, thought, reasoning, planning etc)

Question 13

statement:

hippocampus is hub where information from other locations converge

Answer 13

-

Question 14

output from the hippocampus

subcortical = 3 / cortical = 2

Answer 14

subcortical =

• amygdala
• septal nuclei
• thalamus (via mammillary bodies) - modulating signals to show how important they are - show how much attention should be shown

cortical =

• limbic cortex
• all association areas

Question 15

what do lesions in the hippocampus result in?

2 things

Answer 15

• impaired spatial/navigational skills (animal studies - eg rats in the maze)
• anterograde amnesia (patient HM)(can still learn skills and learn implicitly - just no recognition of learning)

Question 16

information:

rats have a much larger olfactory bulb (relative)
and a relatively smaller cerebral cortex

cerebral cortex is main thing in human brain = increases ability to learn

but assumes cerebral cortex is involved in learning

Answer 16

-

Question 17

what is the amygdala directly connected to?

2 things

Answer 17

lateral hypothalamus and therefore the endocrine system

Question 18

what is the amygdala involved in?

Answer 18

learning biologically significant information

Question 19

what happens when the amygdala is electrically stimulated?

Answer 19

fearful and aggressive behaviour

Question 20

what happens when the amygdala is lesioned?

Answer 20

failure to learn ‘conditioned fear response’

animals can’t learn that a stimulus signals danger

eg rats that don’t get on wooden bench when bell sounds to signal an electric shock

Question 21

what is the septal nuclei involved in?

Answer 21

the feeling of reward / processing reward

Question 22

what happens when the septal nuclei is electrically stimulated?

Answer 22

it is pleasurable

animals continue to self-stimulate (if given access to electrode)

Question 23

what happens if septal nuclei is lesioned?

Answer 23

causes over activity and results in a failure to calm down