Implicit memory
How do instructions differ between implicit and explicit memory tests?
In implicit tests, participants are not asked to use memory to complete the task
What is the difference between flat RA and graded RA?
Flat retrograde amnesia involves similar impairment for memories preceding the damage, whereas graded RA involves decreasing memory impairment with the age of the memory (so childhood is better remembered than the years prior to the damage, for example)
List 3 causes of anterograde amnesia
Lesions, blow to head, brain infection, stroke, ECT, korsakoff's, hypoxia
The word fragment completion studies presented in class showed that implicit memory is forgotten ________ and does not require _________.
Slower (than explicit memory); attention
List 4 cognitive abilities that are intact in those with amnesia
Skill learning, semantic memory, phonological STM, simple perception, implicit memory, delay conditioning
Describe the declarative vs procedural explanation of amnesia
Declarative (explicit) - memory that can be verbally reported (like knowledge and events), MTL dependent, but slowly consolidated to cortex
Procedural (implicit) - learning that can’t be verbalized or consciously expressed, cortex dependent
Describe the experiment presented in class about the mere exposure effect
Irregular shapes presented subliminally (1ms exposure, so fast that participants couldn't consciously perceive the shapes)
Chance performance on recognition test
In preference test, they preferred the shape they saw before
Describe contextual cueing & what brain region is involved
In a search task (find the target), targets are paired with backgrounds, and those background-target pairs are repeatedly presented. Over repeated searches, you learn that for a given background, the target always appears in the same location. The resulting increase in search speed is called contextual cueing
Contextual cueing involves the perirhinal cortex/parahippocampal gyrus
How does Activation theory explain amnesia, and what results are problematic for it?
Amnesics can activate existing long term memories (supporting implicit memory), but can't create new associations (which is why they don't have explicit memory)
So MTL damage should disrupt learning of new associations, but a study found that amnesics were not impaired at implicit memory for new information (nonwords)
Describe the experiment finding evidence for contamination between implicit and explicit tasks
Deep LOP appeared to increase implicit memory in a stem completion experiment, but a post-test questionnaire showed that participants often used explicit memory to complete the stems. The LOP effects only appeared in those participants who reported using memory to complete the stems, so this was actually an explicit memory effect after all.
This suggest explicit memory can contaminate implicit memory tasks
What are 3 cognitive processes associated with the hippocampus?
What are 3 that are associated with the perirhinal cortex?
(Besides recollection & familiarity)
Hippocampus: scene perception, trace conditioning, precise visual STM
Perirhinal: conceptual implicit memory, object perception, contextual cueing
Describe the perceptual impairments experiment in amnesia
Hippocampus damage impaired ability to spot odd-one-out for scenes, whereas hippocampus + perirhinal damage impaired ability to spot odd-one-out for objects & faces
What are the neuroimaging findings on priming for visual perceptual implicit memory, and for conceptual implicit memory?
Neural priming in visual perceptual implicit memory is often related to decreased occipital activity
Conceptual priming is related to the perirhinal cortex
List 5 impairments that those with MTL damage can have
Autobiographical/episodic memory, trace conditioning, contextual cueing, precise perception, precise STM, conceptual implicit