144 ❯ Step 4. Review the Knowledge You Need to Score High
even if we’ve never been to a particular elementary school, we expect it to have teachers,
young students, a principal, classrooms with desks and chairs, etc. Connectionism theory
states that memory is stored throughout the brain in connections between neurons, many
of which work together to process a single memory. Changes in the strength of synaptic con-
nections are the basis of memory. Cognitive psychologists and computer scientists interested
in artificial intelligence (AI) have designed the neural network or parallel processing
model that emphasizes the simultaneous processing of information, which occurs automati-
cally and without our awareness. Neural network computer models are based on neuronlike
systems, which are biological rather than artificially contrived computer codes; they can learn,
adapt to new situations, and deal with imprecise and incomplete information.Biology of Long-Term Memory
According to neuroscientists, learning involves strengthening of neural connections at
the synapses, called long-term potentiation (or LTP). LTP involves an increase in the
efficiency with which signals are sent across the synapses within neural networks of long-
term memories. This requires fewer neurotransmitter molecules to make neurons fire and
an increase in receptor sites. Where were you when you heard about the 9/11 disaster? Like
a camera with a flashbulb that captures a picture of an event, you may have captured that
event in your memory. A flashbulb memory, a vivid memory of an emotionally arousing
event, is associated with an increase of adrenal hormones triggering release of energy for neural
processes and activation of the amygdala and hippocampus involved in emotional memories.
Evidence from electrophysiology, neuroimaging, computational modeling, and neu-
ropsychology shows that memory function is more integrated rather than isolated in
specific brain areas. Although memory is distributed throughout the brain, in multiple
memory systems, specific regions are more actively involved in both short-term and long-
term memories. The role of the thalamus in memory seems to involve the encoding of
sensory memory into short-term memory. STM seems to be located primarily in the pre-
frontal cortex and temporal lobes. The hippocampus, frontal and temporal lobes of the
cerebral cortex, and other regions of the limbic system are involved in explicit long-term
memory. Destruction of the hippocampus results in anterograde amnesia, the inability
to put new information into explicit memory; no new semantic memories are formed.
Another type of amnesia, retrograde amnesia, involves memory loss for a segment of the
past, usually around the time of an accident, such as a blow to the head. This may result
from disruption of the process of long-term potentiation. Studies using fMRI indicate that
the hippocampus and left frontal lobe are especially active in encoding new information
into memory, and the right frontal lobe is more active when we retrieve information. A
person with damage to the hippocampus can develop skills and learn new procedures. The
cerebellum is involved in implicit memory of skills, and studies involving patients with
Parkinson’s disease have indicated involvement of basal ganglia in implicit memory too.Retrieving Memories
Retrieval is the process of getting information out of memory storage. Whenever we take
tests, we retrieve information from memory in answering multiple-choice, fill-in, and essay
questions. Multiple-choice questions require recognition, identification of learned items
when they are presented. Fill-in and essay questions require recall, retrieval of previously
learned information. Often the information we try to remember has missing pieces, which
results in reconstruction, retrieval of memories that can be distorted by adding, dropping,
or changing details to fit a schema.
Hermann Ebbinghaus experimentally investigated the properties of human memory
using lists of meaningless syllables. He practiced lists by repeating the syllables and keeping
records of his attempts at mastering them. He drew a learning curve. Keeping careful rec ords,