Memory

What is Memory? Memory is a system that encodes, stores and retrieves information –Process by which information is taken in, converted to meaningful patterns and then saved until such time as it is needed –E.g., expectancies  stored associations between behaviors and consequences that drive behavior

The Three Stages of Memory

The three Stages of Memory Sensory Memory Working Memory Long-Term Memory

Sensory Memory Real time capture of sensory stimuli –Iconic memory  visual images –Echoic memory  sounds Function  Scan sensory information; select information to focus on and filter everything else out Capacity  12 – 16 items Duration.25 seconds

Sensory Memory Sperling –Designed a study to examine the capacity of the sensory store –Briefly presented a stimulus array; ask subjects to: Report everything you see Report on specific information

D J B W X H G N T M L P

Report everything you see

X Q Y W P L M G S Q T V

Report contents of second row

Working (or Short-Term) Memory Mental work station Functions: –Selects information from sensory store on which to focus attention –Temporary storage site for new information –Processes information so it can be transferred to long-term memory Capacity  7 +/- 2 Duration  approx. 20 seconds

Long-term Memory Function  Permanent storage site for all types of information Capacity  unlimited Duration  unlimited

Three Basic Tasks of Memory Encoding Storage Retrieval

Encoding Process of transforming, coding, or sorting information so that it is in a useable form –E.g., like a card catalog, encoding involves cross-referencing information under multiple categories

Methods of Encoding Chunking  putting multiple pieces of information together into meaningful groups; helps to expand the capacity of working memory –E.g., Can you remember these numbers?

Methods of Encoding Rehearsal –Maintenance rehearsal  involves repeating information over and over Good for maintaining in STM but not useful for transferring to LTM –Elaborative rehearsal  connecting new information with knowledge that is already stored Good for transferring information from STM to LTM

Methods of Encoding Levels of Processing –Deeper processing results in better remembering For example: encoding the word Horse –Visual  (i.e., how it looks) -- It has a capital letter, and is arranged cvccv. –Acoustic  Sounds like course –Semantic  an animal that eats hay that you can ride.

Storage Process by which information is maintained in long-term memory Divisions of LTM –Procedural  memory for mental directions or procedures –Declarative  memory for facts and events Episodic  Stores personal information; memory for events in your life Semantic  Basic meanings of words and concepts

Retrieval Process by which information is accessed from long term memory so that is can be used or modified by new information Depends on how information was encoded and stored

Factors Affecting Retrieval Depth of Processing  retrieval is better –the more deeply information is processed –The more connections that have been formed with existing information Retrieval Cues  Stimuli that help to bring a memory to consciousness Encoding specificity  The more closely the retrieval cues match the cues present at encoding, the more readily the information will be retrieved Mood  biases retrieval of information that is mood- congruent

Retrieval Implicit Recall – Memory that was not deliberately learned or was outside of conscious awareness –Priming – process of providing cues that stimulate retrieval of implicit memories without awareness of connection between the cue and the retrieved memory

Retrieval Explicit – Memory that has been processed with awareness and requires effort and conscious awareness –Recall  Must produce previously stored information (Short answer question) –Recognition  Identify stimulus as having been presented previously (i.e., multiple choice)

H.M. Removed hippocampus and amygdala on both sides of brain to control severe epileptic seizures Result  severe anterograde amnesia –Inability to form new memories –Unable to transfer information from short-term to long- term memories Memory deficits are uniquely for declarative but not procedural memories

Forgetting or Memory Lapses Serial Position Effect –First and last items on a list block retrieval of information in the middle Context – dependent learning –Memory fails when context at retrieval differs from context at encoding Reconstructive nature of memory –Take in information, discard details, organize rest in meaningful patterns –At retrieval, reconstruct details based on fragments that are stored