Memory (forms)
Memory is the ability to store, retain, and retrieve information. It can be divided and classified in many ways.
Classification
The first classification is via the duration over which it is retained.
Another classification relates to whether the memory can be consciously and intentionally retrieved.
Memories that can be consciously retrieved are referred to as declarative (or explicit) memories. Those which cannot are called nondeclarative (or implicit) memories. Learning in the episodic system tends to be rapid whereas storage in the semantic system occurs slowly over time and requires multiple exposures (hence the need to repeat the exam questions several times!)
Declarative memories are further divided into semantic (fact based) and episodic (event based) memories.
Implicit (nondeclarative) memories fall into three types.
Memory neuroscience
The hippocampal formation linked with regions of medial temporal lobe and parts of the prefontal cortex are involved with the encoding and retrieval of episodic memories. The memory traces themselves (called engrams) are stored in the neocortex.
Interactions with the hippocampal formation and the amygdala are important for emotional memories.
The basal ganglia and cerebellum are involved in procedural memory.
The amygdala plays a key role in fear conditioning and extinction
The dorsolatereral prefontal cortex (DLPFC) is thought to be important for working memory.
Classification
The first classification is via the duration over which it is retained.
| Memory type | Description |
|---|---|
| Ultra-short term memory | This is also called sensoric or echoic/iconic memory and lasts from milliseconds to seconds |
| Short-term memory (The working memory model was proposed by Baddeley in 1974 and is a more sophisticated model to describe the short-term memory) | Lasts from seconds to minutes. A feature of short-term memory is capacity limitation with most people being able to retain about seven items in short-term memory. Features of the working memory:
|
| Long-term memory | This refers to the retention of information from minutes to an entire lifetime. This does not appear to be capacity limited and results from changes to neuronal structure |
Another classification relates to whether the memory can be consciously and intentionally retrieved.
Memories that can be consciously retrieved are referred to as declarative (or explicit) memories. Those which cannot are called nondeclarative (or implicit) memories. Learning in the episodic system tends to be rapid whereas storage in the semantic system occurs slowly over time and requires multiple exposures (hence the need to repeat the exam questions several times!)
Declarative memories are further divided into semantic (fact based) and episodic (event based) memories.
Implicit (nondeclarative) memories fall into three types.
- Procedural - the acquisition of sensorimotor, perceptual, or cognitive skills through repeated exposure
- Priming - the facilitation of a response to an item previously encountered
- Conditioning and extinction
Memory neuroscience
The hippocampal formation linked with regions of medial temporal lobe and parts of the prefontal cortex are involved with the encoding and retrieval of episodic memories. The memory traces themselves (called engrams) are stored in the neocortex.
Interactions with the hippocampal formation and the amygdala are important for emotional memories.
The basal ganglia and cerebellum are involved in procedural memory.
The amygdala plays a key role in fear conditioning and extinction
The dorsolatereral prefontal cortex (DLPFC) is thought to be important for working memory.
