Definition: The immediate and very brief recording of sensory information in the memory system.
Short-Term Memory
Definition: A briefly activated memory system that holds information for a limited duration.
Example: Holding digits of a phone number just long enough to dial it.
Characteristic: Information in short-term memory is often later stored into long-term memory or forgotten entirely.
Long-Term Memory
Definition: The relatively permanent and limitless archive of the memory system.
Contents: Includes knowledge, skills, and experiences.
Memory Systems Overview
Sensory Memory
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Short-Term Memory/Working Memory
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Long-Term Memory
Atkinson and Shiffrin Model of Memory
Another model proposed by Atkinson and Shiffrin focuses on types of storage:
Sensory Memory: Initial stage that briefly holds all sensory information.
Not all sensory input is moved further into the memory system.
Short-Term Memory: Next stage with limited capacity and duration;
Information is forgotten if not encoded further.
Memory often held temporarily until encoding occurs.
Long-Term Storage: Information encoded semantically moves here for later retrieval.
Working Memory
Research has updated Atkinson and Shiffrin's model by adding the concept of working memory:
Definition: A newer understanding of short-term memory; it involves conscious, active processing of incoming sensory information and information retrieved from long-term memory.
Components of Working Memory:
Central Executive: A memory component that coordinates activities of the phonological loop and visuospatial sketchpad.
Phonological Loop: An auditory memory component that briefly holds auditory information.
Visuospatial Sketchpad: A memory component that briefly holds visual and spatial information about objects' appearance and location in space.
Suggested by Alan Baddeley as a modification to the concept of short-term storage.
Selective Attention
Definition: It helps us focus on new information while integrating long-term memories into working memory.
Example: Understanding words by relating them to previous knowledge based on context; such as knowing where your car is parked, which relies on both short-term and long-term memory.
Neurogenesis
Definition: The formation of new neurons.
Long-Term Potentiation (LTP)
Definition: An increase in a nerve cell's firing potential after brief, rapid stimulation; considered a biological basis for learning and memory.
Relationships:
LTP is both a cognitive function and a biological one.
Connections are made and strengthened when new information is learned and used.
Some stimulation may contribute to the creation of new neurons.
Mechanism: At the synaptic level, a neuron's increased potential to fire is linked to learning and memory; repeated stimulation of certain neural pathways enhances the likelihood of future firing with less prompting.
Studies on Memory and LTP
Studies using drugs that block or enhance long-term potentiation have demonstrated its critical role in memory formation.
Brain Areas Involved: Different types of memory are associated with specific brain areas:
The cerebellum is connected to implicit memories (unconscious knowledge).
The hippocampus is linked to explicit memories (conscious recall).