Modal Model of Memory

Visual Sensory Memory
"Iconic" Memory

• Movies, "sky writing", lightening
• Sperling's experiments

Properties of Sensory Memory

• Very large capacity
• Decays very quickly
• Not perceptually processed
• Bright vs. dark "mask"
• Spatially organized
• Row cue vs. letter/digit cue

Functions of Sensory Memory

• Sensory memory allows the visual system to continue to extract information about the environment even though it is not visible.
• Sensory memory is "worth" about 100 milliseconds (1/10th of a second) of extra processing time.

Short-term "Working" Memory

• Intermediate memory system "between" sensory memory and long-term memory.
• Consists of elements of long-term memory that are activated or objects of attention or both.
• Everything in conscious awareness is "in" short-term working memory.

Properties of Short-term Memory

• Contains perceptually processed information.
• Information is maintained in STM by rehearsal.
• Reciting a phone number; memory span
• Capacity is limited by how much can be rehearsed in about 2 seconds.
• Word-length effect

Properties of Short-term Memory

• The capacity of short-term memory can be increased by "chunking."
• The bigger the chunks, the more can be remembered.
• A student at CMU acquired a memory span of over 80 digits using chunking.

Functions of Short-term Memory

• Mental activities often require coordinating several pieces of information or inputs. We may need to process inputs one at a time, and then integrate them.
• Examples: Language comprehension, mental computation, planning.

Properties of Long-term Memory

• Very large capacity
• Organized according to meaningful relations
• The major cause of forgetting is interference
• Reconstructive

Principles of Long-term Memory

• Elaboration
• Encoding-Retrieval Match
• Massed vs. Distributed Practice

Elaboration

• Material is remembered better if it is elaborated precisely and meaningfully.
• Elaborations are facts or features that are associated with or expand upon to-be-remembered material.
• Think about meaning, relationships, & differences.

Implications

• Organization

Implications

• Intentional vs. Incidental Learning
• Hyde & Jenkins

Summary

• Sensory memory: Large capacity, temporary, register of physical stimulation, allows visual system to continue to process information.
• Short-term memory: Limited capacity, rehearsal, perceptually processed, "chunks", needed to integrate information over time and space.
• Long-term memory: Very large capacity, organized according to meaningful relations; elaboration.