Hebb (1949) suggested that we might store short-term memories by a reverberating circuit, in
which neuron A excites neuron B, which excites neuron C, which then re-excites neuron A.
Hebb further proposed that storing something in short-term memory for a sufficient period of
time made it possible for the brain to consolidate (strengthen) it into long-term memory,
presumably by building new synapses or other structural changes. If anything interrupts the
rehearsal of short-term memory before consolidation completes its course, the information is
simply lost (Kalat, p. 388).
The correct answer is:
Hebb concluded that short-term memory [was a temporary holding station on the way to
long‑term memory].
Question 2
Diane is in her 70’s and suffers from Down syndrome. There are a large number of elderly
people diagnosed with Down syndrome and.
The first major clue to the cause of Alzheimer’s was the fact that people with Down
syndrome (a condition generally linked to cognitive impairments) almost invariably get
Alzheimer’s disease if they survive into middle age. People with Down syndrome have three
copies of chromosome 21 rather than the usual two. This fact has led investigators to examine
chromosome 21, where they found a gene linked to many cases of early-onset Alzheimer’s
disease. Later researchers found two more genes linked to early-onset Alzheimer’s. In this
case, “early” means before age 60. For the much more common late-onset condition, many
genes increase or decrease the risk, but none has a large effect. Many late-onset cases relate
to epigenetic changes in certain genes (Kalat, p. 391). Korsakoff's syndrome is a disorder that
primarily affects the memory system in the brain, it usually results from a deficiency of
thiamine (vitamin B1). Parkinson's disease is a progressive nervous system disorder that
affects movement, while Huntington's disease is a rare, inherited disease that causes the
progressive breakdown (degeneration) of nerve cells in the brain which impacts on a person's
functional abilities and usually results in movement, thinking (cognitive) and psychiatric
disorders.
The correct answer is:
, Diane is in her 70’s and suffers from Down syndrome. There are a large number of elderly
people diagnosed with Down syndrome and [Alzheimer’s disease].
Question 3
A rat is positioned in a radial maze that it has already completed several trials in. Rats with
injury to their hippocampus are more prone to.
Explanation
Several types of evidence demonstrate the importance of the hippocampus and nearby areas
for spatial memory. Consider a radial maze with several arms — typically eight — some or
all of which have a bit of food at the end (see Kalat, p. 400, Figure 12.11). A rat’s best
strategy in a radial maze is to explore each arm once and only once, remembering where it
has already gone. In a variation of the task, a rat might learn that the arms with a rough floor
never have food or that the arms pointing toward the window never have food. Thus, a rat can
make a mistake either by entering a never-correct arm or by entering any arm twice. Rats
with damage to the hippocampus can learn to avoid the never-correct arms, but even after
much training they often enter a correct arm twice. That is, they forget which arms they have
already tried.
The correct answer is:
A rat is positioned in a radial maze that it has already completed several trials in. Rats with
injury to their hippocampus are more prone to [enter one of the correct alleys repeatedly].
Question 4
Long-term potentiation (LTP) is produced when two or more axons are stimulated nearly
simultaneously, whereas LTP is produced only weakly, if at all, when only one is stimulated.
This is referred to as.
Explanation
LTP cooperativity refers to the nearly simultaneous stimulation by two or more axons which
produces LTP more strongly than does repeated stimulation by just one axon (CP, p. 408).
The correct answer is:
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