Test 3 - Learning & Memory Flashcards
Working memory
short-term - explicit
Spatial memory
facts & events
long-term - explicit
Habits/motor skills
long-term & implicit
Implicit memory
previous experience aids in task performance without conscious recall
Explicit memory
declarative memory that requires conscious recall (names, facts, events)
Short-term memory
seconds to minutes
Long-term memory
hours to days
Short-term sensitization
- serotonin binds to GPCR receptors
- two pathways activated
2a. DAG -> PKC -> voltage gated Ca (comes in) K (goes out) channels open -> enhance NT release
2b. CAMP -> PKA -> same as above - Ca presence causes sensory neurons releasing more vesicles with glutamate
- sensory input -> sensory neuron -> (5-HTP interneuon = increase glu. increase response) -> motor neuron -> innervates muscle
Long-term sensitization
- serotonin binds to GPCR receptors
- CAMP -> PKA -> CREB
- CREB binds to CRE site which increase gene expression
- Ca in & K out leads to increase neurotransmitter release and increase attraction (the more serotonin synapses the cluster together sensory and motor grow together)
Associate facilitation
Unconditioned Stimulus (US) - “meat”
1. Depolarization - Ca enters
2. activate AC -> CAMP -> PKA
3. PKA increase releases glutamate
4. Glutamate binds to NMDAR on motor neuron which increases Ca and depolarization (retrograde enhances facilitating)
Conditioned Stimulus (CS) - “bell”
1. depolarize sensory neuron - serotonin
2. AC -> CAMP -> PKA
Associative facilitation using Pavlov’s experiment.
The dog smells the meat, which leads to serotonin binding to 5-HT GPCR receptor. Alpha ADP-> ATP -> CAMP -> PKA -> NT glutamate is released, and there is salivation with food. When glutamate binds to NMDAR. Ca increase and leads to depolarization which sends a retrograde signal back to the sensory neuron. Strengthening response so when the bell is heard the sensory depolarizes calcium increases and cycle starts again.
LTP
long-term potentiation - facilitating synapse - excitatory neurotransmitters (high frequency - brief time)
LTD
long -term depression - depressing synapse - inhibitory neurotransmitters - (low frequency - over long period)
Hippocampus in learning and memory
- dentate gyrus: 1st place build emotional connection with memory
- hippocampal region: all memory starts here
- parahippocampal - store memory here
Is the hippocampus more involved in LTP or LTD?
LTP
Hebb’s postulate
axon of cell A is near enough to cell B to excite cell B and repeatedly fire… some growth process/metabolic changes can take place to increase cell A to B communication efficiency
What does Hebb’s postulate refer to?
synaptic modulation & plasticity
Cerebellum in learning and memory
cerebellar repetitive circuitry - control of motor learning
Is the cerebellum more involved in LTP or LTD?
LTD
What cell type is primarily responsible for the GABA release in the cerebellum?
Purkinje cells
- Describe the habitual type of memory and relate this to walking.
Thalamus -> cortex -> ventral striatum
Striatum role in learning and memory
“habitual response”
Ventral striatum
gain access to favorable outcome (habit related)
Dorsal striatum
spatial accuracy, less “reward” based (mostly motor)
What role does the amygdala play in memory formation?
- mediates emotional influence on attention, perception, and regulating emotional responses in the body
- acquiring emotional disposition (fear conditioning)
- modulating memory (emotion enhances memory) (decrease NEPI, Increase activity of amygdala, decrease other brain areas)
What areas of the brain does the amygdala affect, and what are some potential outcomes?
- anterior pituitary - stress hormone release
- DMV - parasympathetic control
- central gray - emotional behavior
- lateral hypothalamus - sympathetic activation
- RPC - reflex potentiation
- Basal nucleus - cortical arousal and attention
How does emotion enhance memory?
emotion = arousing event -> releases epi and glucocorticoids -> increase norepi in amygdala -> increase consolidation of memory and other brain areas (hormonal systems)
- experience and emotional arousal can cause increase norepi
Posterior cortex
organized for serial and parallel processing for each sensory modality
Anterior cortex
similar hierarchy of motor areas, and assc. areas in PFC
Repetition priming
repeating previously presented items as unaltered or fragments of the original - leads to decrease in cortical areas in initial processing of stimulus
What is the role of the prefrontal cortex in learning/memory?
- planning
- higher-order cognition
- working memory
