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memory, behavior, sleep
memory
• store, retain and recall• sensory-short-working-
long term memory• declarative-procedural • hippocampus (epilepsy,
encephalitis, embolia), corpora mamillaria (Korsakoff), nc. basalis magnocellularis Meynerti (Alzheimer), amygdala, basal ganglia, cerebellum
• amnesia retrograde x anterograde
• mechanisms-short: Hebb, NMDA, LTP, LTD
• mechanisms-long: RNA, sprouting, protein
Hebb synapses: synapses that are strengthened due to the coincidence of pre-synaptic neuro- transmitter release and postsynaptic firing
method and depth of processing affect how an experience is stored in memory
• Organization - Mandler (1967) gave participants a pack of word cards and asked them to sort them into any number of piles using any system of categorization they liked. When they were later asked to recall as many of the words as they could, those who used more categories remembered more words. This study suggested that the act of organizing information makes it more memorable.
• Distinctiveness - Eysenck and Eysenck (1980) asked participants to say words in a distinctive way, e.g. spell the words out loud. Such participants recalled the words better than those who simply read them off a list.
• Effort - Tyler et al. (1979) had participants solve a series of anagrams, some easy (FAHTER) and some difficult (HREFAT). The participants recalled the difficult anagrams better, presumably because they put more effort into them.
• Elaboration - Palmere et al. (1983) gave participants descriptive paragraphs of a fictitious African nation. There were some short paragraphs and some with extra sentences elaborating the main idea. Recall was higher for the ideas in the elaborated paragraphs.
learning
• associative=conditioning– classical– operant
• non-associative– habituation– sensitization– place & exploratory
learning– imprinting– insight learning– imitation
• critical period
Imprinting Imprinting is a form of learning closely associated with innate behaviour. Konrad Lorenz conducted
an experiment with Greylag geese
Insight learning = The ability of animals to perform appropriate behaviours on the first attempt in situations
with which they have no prior experience. Insight learning is best developed in primates. A
chimpanzee placed in an area where a banana is hung too high to reach, but where boxes are scattered about,
will "size" up the situation, stack the boxes, climb up and retrieve the banana.
operant conditioning• Reinforcement
a behavior is strengthened, and thus, more likely to happen again – Positive Reinforcement: stronger by
following the behavior with a pleasant– Negative Reinforcement: stronger by
taking away a negative stimulus. • Punishment
a behavior is weakened, and thus, less likely to happen again– Negative Punishment: removing a
pleasant stimulus– Positive Punishment: presenting an
unpleasant stimulus when the behavior occurs
• motivation
behavior• motivation (endogenous x
exogenous-intr-extrinsic)• drive • apetitive behavior• key (sign) stimulus• reward
• reflex – fixed-action pattern – stereotype – instinct – learned behavior
• Konrad Lorenz, Niko Tinbergen and Karl von Frisch shared the 1973 Nobel Prize for physiology or medicine for their work in ethology.
Example: Niko Tinbergen noticed male three-spined stickleback fish responded aggressively
to red trucks passing by their tank. Fixed-Action Pattern: Male sticklebacks
attack other males that enter their territories. Sign stimulus: The red belly of the invading
male. Sticklebacks attacked nonfish-like models with red on the ventral surface.
sleep• unconsciousness from which
the organism can be aroused by sensory stimuli
• a period of repair for a tired brain and body (recuperative theory), or an adaptive mechanism to the long and dangerous darkness of the night (circadian theory)
• serotonergic ascending tracts from the dorsal rapheal nuclei may be responsible for non-REM sleep
• noradrenergic ascending tracts from the locus coeruleus may cause REM sleep
• section A - the cat fell into a coma - their EEG became permanently synchronized
• section B - the cat was only paralyzed, not comatose
• stimulation - the cat "woke up" - according to its EEG
awakeness
• The cholinergic cells are active, so they facilitate sensory thalamus and inhibit the reticular nucleus. The inhibition of the reticular nucleus actually excites the sensory thalamus as well (negative x negative = positive). As a result the thalamus lets all sensory information through, and cortex is highly active and desynchronized dealing with all the input.
sleep - stages
• non-REM– 1. alpha to theta (4-7 Hz)
twitches, (jerks, myoclonus)=drowsiness
– 2. sleep spindles (brain's active blocking of arousals) and K-complex (brief arousal) - stage
– 3. stage 2 plus delta activity– 4. only delta (1-4 Hz)
sleep
• Destruction of the raphe nuclei causes complete insomnia (lack of sleep) for 3 or 4 days, but then, the animal begins to sleep again
REM sleep
• The locus coeruleus is responsible for the paralysis, and the destruction of this area in cats produces "REM sleep without atonia", whereby the sleeping cat moves about in bursts of activity, seemingly enacting its dreams.
