Chapter 6 Memory
− the ability to store and retrieve information over time.
− the process by which we transform what we perceive, think, or feel into an enduring memory.
− the process of maintaining information in memory over time.
− the process of bringing to mind information that has been previously encoded and stored.
− the process of actively relating new information to knowledge that is already in memory.
− memories are a combination of old and new information, so the nature of any particular
memory depends as much on the old information already in our memories as it does on
the new information coming in through our senses.
Visual Imagery Encoding
− the process of storing new information by converting it into mental pictures.
− Visual imagery encoding does some of the same things that elaborative encoding does:
when you create as visual image, you relate incoming information to knowledge already
in memory. Second, when you use visual imagery to encode words and other verbal
information, you end up with two different mental “placeholders” for the items-a visual
one and a verbal one-which gives you more ways to remember them than just a verbal
− Visual imagery encoding activates visual processing regions in the occipital lobe, which
suggests that people actually enlist the visual system when forming memories based on
- the process of categorizing information according to the relationships among a series of items.
- a type of storage that holds sensory information for a few seconds or less.
− a fast-decaying store of visual information
− a fast-decaying store of auditory information
Short-Term Storage and Working Memory
− a type of storage that holds nonsensory information for more than a few seconds but less
than a minute
− Short-term memory is limited in how long it can hold information, and also limited in how much information it can hold.
− the process of keeping information in short-term memory by mentally repeating it.
− combining small pieces of information into larger clusters or chunks that are more easily
held in short-term memory.
− active maintenance of information in short-term storage
− it differs from the traditional view that short-term memory is simply a place to
hold information and instead includes operations and processes we use to work with
information in short-term memory.
− a type of storage that holds information for hours, days, weeks, or years.
− In contrast to both sensory and short-term memory, long-term memory has no
known capacity limits.
The Role of the Hippocampus as Index
− the inability to transfer new information from the short-term store into the long-term
− the inability to retrieve information that was acquired before a particular date, usually
the date of an injury or operation.
− the process by which memories become stable in the brain.
− Shortly after encoding, memories exist in a fragile state in which they can be
easily disrupted; once consolidation has occurred, they are more resistant to disruption.
One type of consolidation operates over seconds or minutes.Another type of
consolidation occurs over much longer periods of time and likely involves transfer of
information from the hippocampus to more permanent storage sites in the cortex.
− The act of recalling a memory, thinking about it, and talking about it with others
probably contributes to consolidation.
− memories can become vulnerable to disruption when they are recalled, requiring them to
become consolidated again.
Memories, Neurons, and Synapses
long-term potentiation (LTP)
− a process whereby communication across the synapse between neurons strengthens the
connection, making further communication easier.
− Long-term potentiation has a number of properties that indicate to researchers
that it plays an important role in long-term memory storage: It occurs in sveral pathways
within the hippocampus; it can be induced rapidly; and it can last for a long time. NMDAreceptor
− a receptor site on the hippocampus that influences the flow of information between
neurons by controlling the initiation of long-term potentiation.
− The hippocampus contains an abundance of NMDAreceptors, more so than in
other areas of the brain. But for these NMDAreceptors to become activated, two things
must happen at roughly the same time.
− First, the presynaptic or “sending,” neuron releases a neurotransmitter
called glutamate which attaches to the NMDAreceptor site on the postsynaptic
or “receiving,” neuron.
− Second, excitation takes place in the postsynaptic neuron. Together, these
two events initiate LTP, which in turn increases synaptic connections by allowing
neurons that fire together to wire together.
Retrieval Cues: Reinstating the past
− external information that helps bring stored information to mind.
Encoding specificity principle
− the idea that a retrieval cue can serve as an effective reminder when it helps rec-create
the specific way in which information was initially encoded.
− the tendency for information to be better recalled when the person is in the same state
during encoding and retrieval.
− the idea that memory is likely to transfer from one situation to another when the
encoding context if the situations match.
Retrieval Can Impair Subsequent Memory
− a process by which retrieving an item from long-term memory impairs subsequent recall
of related items.
Explicit and Implicit Memory
− the act of consciously or intentionally retrieving past experiences
− the influence of past experiences on later behavior, even without an effort to remember
them or an awareness of the recollection.
− Implicit memories are not consciously recalled, but their presence is “implied”
by our actions.
− the gradual acqu