Ch. 7: Learning Flashcards
Memory
The nervous system’s capacity to retain and retrieve skills and knowledge
Information processing theory of memory
Views memory as analogous to a form of how computers process information. There are three stages to this: encoding, storage, and retrieval.
The encoding phase
First phase of memory in information processing theory. The encoding phase occurs at the time of learning, as information is transferred into a format that can be stored in memory.
The storage phase + consolidation
Second phase of memory in information processing theory. The storage phase is the retention of the encoded representation. Neural connections that represent memory become stronger, and new synapses are constructed, which is called consolidation. Through consolidation, encoded information becomes stored in memory
The retrieval phase
The third phase of memory in information processing theory. This stage consists of reaching into memory storage to find and bring to mind a previously encoded and stored memory when it is needed.
Reconsolidation
Once memories are activated, they need to be consolidated again to be stored back in memory. This implies that when memories for past events are retrieved, those memories can be affected by current circumstances, so the newly reconsolidated memories can differ from their original versions. This implies the possibility that memories could be erased by activating them and then interfering with their reconsolidating.
Hebb’s memory model
Psychologist Donald Hebb proposed that memory results from alterations in synaptic connections. In this model, memories are stored in multiple regions of the brain that are linked through memory circuits. When one neuron excites another, some change takes place that strengthens the connection between the two neurons. Subsequently, the firing of one neuron becomes increasingly likely to cause the firing of the other neuron. In other words: “cells that fire together wire together”.
Long term potentiation
A process that is central to the neural basis of memory consolidation. LTP is the strengthening of a synaptic connection by making the post-synaptic neuron more easily activated by the pre-synaptic neuron. LTP serves as a model for how neural plasticity might underly memory.
NMDA receptor on the post-synaptic neuron
Plays a key role in LTP. This type of glutamate receptor responds only when large amounts of glutamate are available in the synapse and the neuron is sufficiently depolarized. LTP leads to an increase in the number of glutamate receptors in the post-synaptic neuron, which increases its responsivity to glutamate released by the pre-synaptic neuron
Equipotentiality
The idea that memory is distributed equally throughout the brain rather than confined to any specific location.
memory regions
Although memory involves multiple regions throughout the brain, not all brain regions are equally involved. A great deal of natural specialization occurs. Because of this specialization, different brain regions are responsible for storing different aspects of information, and different memory systems involve storing different aspects of information. For instance, we know that regions inside the temporal lobes, like the hippocampus, are important for the ability to store new memories. Thus, memory for sensory experiences, such as remembering something seen or heard, involves the reactivation of the cortical circuits involved in the initial seeing or hearing.
The medial temporal lobes
The middle section of the temporal lobes. It is responsible for the formation of new memories. The actual storage, however, occurs in the specific brain regions engaged during perception, processing, and analysis of the material being learned.
3 part model of memory
Composed of: sensory memory, short-term memory, and long-term memory.
Sensory memory + visual and auditory sensory memory names
Temporary memory system closely tied to the sensory systems. It is not what we usually think about when we think about memory because it only lasts a fraction of a second. In fact, normally we are not aware that it is operating. Visual sensory memory is called iconic memory, auditory sensory memory is called echoic memory.
Short term memory
When we pay attention to something, the information passes from sensory stores to short-term memory. Initially this was only seen by researchers to be a buffer or a holding place for memories, but a more contemporary model has emerged called working memory. This storage system actively retains and manipulates multiple pieces of temporary information from different sources. Information remains in working memory for 20-30 seconds. It then disappears unless you actively prevent that from happening (by rehearsing it or otherwise monitoring it)
Memory span and chunking
Working memory can hold a limited amount of information. Miller noticed that the number is generally 7 items (though modern research has found it to be lower), which is referred to as the memory span. Meaningful units are easier to remember than nonsensical ones. This process of breaking down information into meaningful units is called chunking. Chunking is an interplay of the long term system and the working memory system, as to chunk information properly, a person needs to use his prior experiences and memories to add significance to the information.
Long term memory
The relatively permanent storage of information. Unlike computer storage, human long term memory is nearly limitless. Long term memory is different from working memory in two key ways: it has longer duration, and it has a far greater capacity.
Serial position, primacy, and recency effect
People tend to remember items at the start and end of a list better than those in the middle. The primacy effect refers to the better memory that people have for items presented at the beginning of the list. The recency effect refers to the better memory that people have for items presented at the end of a list (ie. the most recent items). Delays in the asking for the repeating of information caused the recency effect to fade but not the primacy effect.
