Psy 342 Learning & Memory


Amnesia—Chapter 11 

I.  The Anatomy of the Brain

 

sheep brain dissection

 

III.  Where are Memories Located in the Brain?

      A. Localized view—memories are located in specific sites in the brain 

B. Distributed view--memories are distributed across the brain. 

 IV.  Amnesia 

A. Case studies 

1. SP--stroke affected both medial temporal lobes, the left hippocampus, and other neighboring areas 

Severe anterograde (except digit span) and retrograde amnesia.   

Ability to name objects was severely impaired

 Lost recent and remote autobiographical

 Able to learn new procedural

 

2. Clive Wearing—encephalitis, an inflammation of the central nervous system

         Problems in semantic memory

         Severe losses in episodic memory 

Lost the capacity for new learning, but coined new definitions for words, remaining consistent in their use 

CT and MRI scans revealed structural changes in both temporal lobes with dilations of certain regions compared to their normal state.   

Hippocampus was severely damaged

 

B. Performance Patterns in Amnesia

 

1. Retrograde amnesia—losing past memories 

In differential retrograde amnesia, some types of information are lost, while others are retained 

Retrograde amnesia is assessed by a variety of instruments to measure autobiographical memory, semantic memory, and episodic memory 

2. Anterograde Amnesia—Problems acquiring new info. 

If injury is mild, can regain the ability to learn new info. 

Have patient learn new info. 

Wechsler Memory Scale 

3. Spared Memory Functions—Some retain ability to acquire perceptual skills, motor skills, cognitive skills, and, under very specialized conditions, new declarative knowledge.  

Implicit memory and memory for skills 

       Working Memory 

       Semantic Memory   

Acquiring new declarative info.

 

C. Explaining Amnesia

  Interference hypothesis

  Retrieval hypothesis

  Encoding hypotheses

       Consolidation hypotheses

         Context memory deficit hypothesis

         Error monitoring hypothesis

 

V.   Implicit Memory 

A. Definitions 

Learning instructions—incidental or intentional 

Type of test—implicit or indirect vs. explicit or direct

Memory used by S— implicit (nonconscious) or explicit (conscious)

 Implicit Learning—acquiring knowledge about stimuli without a conscious attempt.

 

B. Explicit vs. implicit measures  

Explicit (direct) memory test—Ss are instructed to remember information   

Examples—recall, recognition

 Implicit (indirect) memory test—Ss perform a cognitive task which is facilitated by previous experience with the material.  

Examples—word-stem completion, word-fragment completion, repetition priming