Learning, Memory and Emotions Flashcards
medial temporal lobe
- includes hippocampus and parahippocampal regions
- works with other regions of the cerebral cortex
- together, they form, organize and consolidtae and retrieve memories
four major lobes of the cerebral cortex
- frontal, pareital, temporal, occipital
- processs sensory info ausch as smell, taste, sight and sound
- other regions will integrate the sensory inputs to enable us to understand our environment and encode memories
declarative memory
- memory for facts, data, events
- We can consciously recall and describe information
- can be semantic or episodic
semantic memories
- cultural knowledge, ideasm concepts about world
involves cortical regions well beyond the hippocampus
episodic memories
- unique representations of your personal experiences
- mentally recalling sights, sounds, time, space, and emotions associated with an experience
amygdala
- mediates the emotional significance attached to memories of events and experiences
- paried structure consisting of two almond-shaped regions
- modulates the fight-or flight response linked to survival
parahippocampal region
- aids the hippocampus in encoding the “what” of episodic memories rather than the “where” or “when”
episodic, semantic memory are what form
- they are the long-term form of declarative memory
long-term form of declarative memory
- stored throughout a braod netowrk of cortical areas- people with amnesia can retrieve this form of memory but are not able to form new ones
working memory
- temporary type of declarative memory
- form of short-term memory that lets you remember things such as :
- a phone number, a sum, a visual image, or other data pointed needed now and in the immediate future
true or false: brain possesses an unlimited capacity for short term memory
- false:
- the brain seems to have an unlimited capacity for LONG-TERM memory
- but, short-term memories are limited to relatively small amounts of data AND for a limited amount of timeq
when are short-term memories accessible
- when they are being processed and manipulated
- unless being transferred to long-term, they are lost after only a few seconds and are unretrievable
Pre-frontal cortex (PFC)
- coordinates some aspects of working memory
- controls attention, decision-making, long-term planning
- some are monitor info from long-term memory as we;; as coordinating working memory from multiple brain regions
when is the PFC particularly active
- when people concentrate on keeping something in mind(like a phone #)
- neurons heare fire in spurts which keeps info active in the working memory
- working memory is not lost in amnesia
spatial memory
- another facet of declarative memory
- identified in studeies showing that discrete areas and individual neurons in the brain are dedicated to processing specific types of information
- ex. navagational memories for creating mental maps are tied to specific neurons
- “place cells” would light up as you move through a familiar area
what can cause changes in the hippocampus
- learning complex navigational routes
grid cells
- do not represent particular locations
- located in the entorhinal cortex (near hc)
- rep coordinates that allow brain to track ur position in space when landmarks/cues are absent.
nondeclaritive memory
- aka implicit/procedural
- stored + retroieved w/o concious effort
- used when performing learned motor skills… speaking, bike
- not lost in amneisa (patients with amnesia are still able to acquire new skills)motor
where are memories located
- different types of memories are encoded in separate but interacting regions of the brain
what three areas are especially important for motor learning
- basal ganglia (habit center), cerebellum (motor control, coordination), prefrontal cortex
how is your brain able to form memories and rewire itself
- in response to experience because circuits in brain change at synapses
synaptic plasticity
- the ability of a synapses to remodel itself
what does encoding a new long-term memory involve?
- persistent changes in number and shape of synapses
- changes in in neurotransmitter release
- changes in number of receptors on post-synaptic membrane
process of transferring info from pre to post synaptic neruon
- pre transforms an electrical signal into the release of chemical messengers called neurotransmitters that diffuse across gap
- after neurotransmitters have bonded to the receptors, the receptors unleash a cascade of molecular events that change the message back into an electrical signal
important animal model for studying synaptic plasticitty
- sea slug (Aplysia californica)
- nerve cells are relatively few and easy to observe
what faciliates long-term changes in sypatic structure
- changes in gene expression
NMDA
- glutamate receptor
- N-methyl-d-aspartate
cAMP
- molecule
- reponse element binding protein
what molecule, protein, and receptor are important in foundation of long-term memories
NMDA receptor, cAMP, and reponse element binding protein CREB
two important processes for synaptic plasticity
LTP, AND LTD
LTP
long-lasting increase in synpatic strength
- occurs in many brain regions especially hippocampus
LTD
- decreases a synapses’ effectiveness
how does experience physically change our brain
- through LTP
- essential for long-term memory consolidation
hipposcampus
- reponsible for encoding new memories
- LTP has been studied extensively here
what does LTP generally involve
- an increase in the number of glutamate receptors on post synaptic neuron
glutamate
most prevalent neurotransmitter in mammalian neverous systen
- binds to several types of receptors
NMDA and AMPA
- ion channels
- receptors
- after bdingind to glutamate, they permit calcium, sodium ions in the cell
how to strengthen a synapses
- increase number of receptors on post cell
- allows entry of more electrically conductive ions
calcium ions
- function as second messengers
- signal molecules that set off a chain of molecular events within cells
LTP and calcium
- boosts concentration of calcium ions inside a post-synpatic cell
LTD and calcium
increases calcium to a lesser degree inside post than LTp
what do the differening concentrations of calcium do?
- activate different enxymes
- kinase proteins (LTP)
- phosphatases (LTD)
- enzymes modify synapse, making it more or less efficient at relaying nerve impulses
how is CReb ACTIVATDD
-Continued stimulation through repetitive experience
how are the synpatic changes stabilized
- a series of molecular events in LTP
- the increase in calcium ions in post cell activates cAMP
- this activates several kinds of enzymes
- some of these ensymes increase the number of synaptic receptors
- this makes the synapse more sensitive to neurotransmitters
- Continued stimulation through repetitive experience activates CREB.
what does CREB do in the neuron after ativated
- acts in the nucleus
- switches on a series of genes
- many of these genes direct protein synthesis
- among these proteins produced are neurotrophins
neurotrophins
- stimulate growth of the synapse and structural elements to stabilize increase sensitivity to neurotransmitters
- this whole process, the molecular cascadem is essential for memories to become long-term
where are declarative memories encoded
- in the hippocampus
- then, they are transferredto the frontal lobes for long-term storage and consolidation
what happens to the hippocampus overtime
- it becomes less important for retrieving older memories as the frontal cortex takes on that role instead
what could artifical manipulation of synpatic plasticity do for people?
- new treatements for synapse-related neruological disorders
- eradication of harmful memories (PTSD)
- or for boosting our ability to learn and remember
emotional memory
- another type of nondeclarative memory
- learned emotional responses become attached to stimuli after repeated exposure over time
six basic emotions
- anger, fear, surprise, dsigust, joy, sadness
brain structuresmost closely linked iwth emotions
- amygdala, insula (insular cortex), periaqueductal gray (in midbrain)
how do the brain structures linked iwth emotion work together?
- the neurons from the PFC, amygdala, and insula project to the periaqueductal gray
- it has reciprocal connections with the central nucleus of the amygdala and projections to thalamus, hypothalamus brainstem, deep layers of spinal cord
what does the amygdala do
- integrates emotions, emotinoal behaviour, motivation
- interpretes fear, reward
what learningis very dependent on the amygdala
- classical conditioning
- assoicated a stimulus with reward or punishment
insula
- you experience disgust through this
- involved in feeling and anticipating pain]
- takes in system-wid inputs and subjective feelings about them
- links feelings, internal physiological states, social emotions and conscious actions
periaqueductal gray
- lcoated in a region where incoming sensory information is acted on by higher brain centers
- is tied to pain perception, stress response, (defensive and reproductive behavirous)
- maternal attachment, and anxiety
- here, the receptors for pain-reducing compound such as morphine and oxycodone are clustered.
why does emotionally centred decision-making change with age
- possibly because the lateral prefrontal cortex (responsible for self-regulation) matures gradually in adolescents
- Teen’s developing brains and high sensitivity to peer acceptance may be related to their increased tolerance for risky behaviors.
why might older adults make more risky decision
- PFC function diminshes with agw
dopaminergic neruons
- relatively few neruons int he mammalian central nervous system generate the neurotransmitter dopamie
- influence multiple brain functions (voluntary movement and a variety of behavioural processes such as mood, reward, addiction, stress and memory)
why is somethig very rewarding easy to remember
- dopamine influences the synapses in the entire reward pathway to create emotional associations with rewards
reward pathway
hippocampus, amygdala, and the prefrontal cortex
mesolimbic pathway
aka reward pathway
- major pathway for dopamine
- connects the midbrain’s ventral tegemental area (VTA) to the nucleus accumbens
- incolced in cognitive processing of rewards and motivation
when are nerons that release dopamine activated
- in response to signals that a reward will be given
what happens when a reward is greater than atnciipated
- dopamine signaling increases and vice versa
what if a reward is correctly predicted
- ## does not elicit changes in dopamine signaling and all remains the same
why do dopaminergic reposnses vary among people
- becasue some people\s brains response more strongly to rewards than punishments and vice cersa
what is noticable in “go-getters”
- greater dopamine singaling in the striatum and prefrontal cortex
- these areas are known to impact motivation and reward
what happens when there is aberrant (differning from normal) circuitry)
- innapropriate aggression
- this is a symptom of some neuropsychiatric disorders
lateral habenula
https://www.google.com/search?q=lateral+habenula&rlz=1C1CHZN_enCA923CA923&sxsrf=ALeKk03bgUD4KY6qfs936EQw9c1O2aiIwA:1619132204951&source=lnms&tbm=isch&sa=X&ved=2ahUKEwjS8q2_-ZLwAhULKawKHS8iBpAQ_AUoAXoECAEQAw&biw=1920&bih=937#imgrc=AgMbnOdKFNXrAM
- major node in reward circuitry
- encodes punishment
- doest this by inhibiting dopamine dopamine release
dysfunction of the lateral habenula
- linked to disorders involing innappropriate aggression
amygdala emotions
- been assoicated with negative emotions
- stimulating some areas can trigger rage and aggression while removing specific sections of the amygdala in lab animals makes the more docile
what else can aggression result from as suggested by recent studies in lab animals
- inappropriate activation of the brain’s reward systems in response to violent social stimuli
