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memory, behavior, sleep
memory
• store, retain and recall
• sensory-short-workinglong 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 presynaptic 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 threespined 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.