Slide 1 Flashcards
Describe PTSD
- post traumatic stress disorder
- recurring/disturbing memories of certain events
Define learning
- how experience changes the brain
- involves neuroplasticity
Define neuroplasticity
brain’s ability to modify synaptic connections as a result of experience
Define memory
refers to how info is stored
and later retrieved
What is an engram?
- memory trace
- physical trace or representation in brain
- of what has been learned
What did Karl Lashley study?
localisation of language function
Describe Lashley’s process of experimentation
- trained rats to run mazes of various levels of difficulty
- disrupted connections between brain areas
- or removed parts of the cortex
Describe Lashley’s findings
- no single cut or combination of cuts
- interfered w/ rats learning and memory of a maze
- only large lesions disrupted performance
What two principles did Lashley come up with to summarize his observations?
- equipotentiality
- mass action
Describe Lashley’s principle of equipotentiality
- brain has ability to use intact part of brain
- to do what damaged part of brain can no longer do
Describe Lashley’s principle of mass action
- learning/mem deficits
- are proportional to amount of brain damage
What was Lashley’s conclusion?
- memories not localized to specific areas
- memory storage distributed over large parts of the cortex
What did Richard Thompson and his colleagues study?
- classical conditioning
- eg. eyeblink conditioning
Describe Pavlovian conditioning
Dog responds to a bell by salivating because it associates the bell with the smell of food
In Pavlovian conditioning, what is the role of food
unconditioned stimulus
In Pavlovian conditioning, what is the role of salivation in response to food?
unconditioned response
In Pavlovian conditioning, what is the role of a bell
conditioned stimulus
In Pavlovian conditioning, what is the role of salivation in response to the sound of a bell
conditioned response
Describe eyeblink conditioning
- subject responds to a tone by blinking
- because he associates the tone with a puff of air
In the eyeblink conditioning experiment, which one is the conditioned stimulus and which is the unconditioned stimulus
conditioned stimulus: tone
unconditioned stimulus: air puff
Which part of the brain stores memory for the eyeblink conditioning
cerebellum
Why did Lashley fail while Thompson succeeded?
- complex tasks like maze learning can rely on more distributed areas of the brain
- Lashley’s methods less precise
Describe Atkinson and Shiffrin’s memory model
- 3 stages
- sensory memory
- short term memory
- long term memory
Define sensory memory
- copy of sensory info
- that you’ve just seen/heard/tasted
How long does sensory memory last?
-few seconds or less
What is the capacity of sensory memory?
difficult to be determined since so short
Where is sensory memory thought to be stored
primary sensory areas
How long does short term memory last?
few seconds - minutes
What is the capacity of short term memory?
- 7 items
- +/- 2
What is long term memory?
-‘permanent memory’
Duration of long term memory
-minutes - years
What is the capacity of long term memory
virtually unlimited capacity
How are memories transformed from short term to long term?
rehearsal
What is the effect of emotional response on memory?
emotional response can enhance memory
What part of the brain is associated with emotional response to memory?
amygdala
Define explicit memory
- memory for info that one recognizes as a memory
- requires conscious thought
What are 2 types of explicit memory
- episodic
- semantic
Define episodic memory
- memory for events
- eg. first day of school
Define semantic memory
-memory for facts
Define implicit memory
memory for tasks that do not require conscious awareness
What is another name for explicit memory
declarative
What is another name for implicit memory
non declarative
What brain area is responsible for explicit memory
medial temporal lobe (diencephalon)
What brain area is responsible for the procedural section of implicit memory
Striatum
What brain area is responsible for the priming/perceptual section of implicit memory
neocortex
What brain area is responsible for emotional responses in classical conditioning?
amygdala
What brain area is responsible for skeletal responses in classical conditioning?
cerebellum
What part is responsible for non associative learning of implicit memory
reflex pathways
Define amnesia
- long term memory impairment
- inability to retain info for more than a few minutes
Cause of amnesia
damage to brain areas responsible for memory consolidation, storage, processing, recall
Two types of amnesia
- anterograde
- retrograde
Define anterograde amnesia
inability to form new memories after brain damage
Define retrograde amnesia
inability to recall memories prior to brain damage
What type of surgery did HM undergo to treat his epilepsy?
- bilateral medial temporal lobectomy
- removed amygdala, hippocampus, adjacent cortex (rhinal)
Name 4 consequences of HM’s surgery
- reduced seizure effects
- higher IQ
- normal perceptual/motor abilities
- severe amnesiac effects
True or false: HM’s short term memory was still functional
true
HM could not form new memories - what type of amnesia is this?
- anterograde amnesia
- ie. explicit memory deficit
What is temporally graded retrograde amnesia?
- remote events more easily accessible
- than events occurring right before the trauma
Which memory tests did HM do fine in and what does it show?
- mirror drawing test
- incomplete pictures test
- his implicit/learning memory was intact
3 major effects of HM case
- proof of existence of diff types of memory
- challenged view that mnemonic functions are equally represented in the brain
- supports diff stages of storage in STM and LTM
What is the cause of Korsakoff’s syndrome
-thiamine deficiency due to chronic alcohol consumption
What is the effect of Korsakoff’s syndrome
-retorgrade and anterograde amnesia
______ is a unique symptom of Korsakoff’s syndrome
confabulation
Define confabulation
- memory error resulting in a fabricated account of the past
- without the conscious intention to deceive
In Korsakoff’s syndrome, which brain areas are affected?
- medial diencephalon (thalamus)
- prefrontal cortex
What is Alzheimer’s disease?
- progressive memory loss associated with aging
- common cause of dementia
What is the cause of Alzheimer’s?
reduction in acetycholine
Effects of alzheimers
- pathological changes in the brain
- extensive neural degradation
- amyloid plaques
- neurofibrillary tangles
Describe the process of a concussion resulting in amnesia
- blow to the head
- coma
- regains consciousness
- confusion
- retrograde amnesia for events right before event
- anterograde amnesia for events during confusion
Which type of amnesia can electroconvulsive therapy produce?
retrograde amnesia
3 things we have learned from studying people with amnesia
- there are diff types of memory
- there are diff stages of memory
- diff brain regions involved
What are the limitations of studying people with amnesia?
- lesions are not specific or complete
- studies of 1 person may not be generalizable
- difficult to control
What are the limitations of studying HM as an exemplary subject of amnesia?
- small parts of hippocampus were intact
- damage to more than 1 brain area
