9: Memory part 2 Flashcards
What is the delayed match to sample task?
-In this delayed nonmatch to sample task:
a. A food reward is placed under an object
b. The door is opened and the monkey can
retrieve the food
c. After a delay, a food reward is placed under
a new object
d. The door is opened and the monkey can
retrieve the food under the non-matched item
○ Monkeys can perform this task and be trained very well
• Monkeys are trained to perform this task, then learning and memory can be observed
What is the delayed match to sample task? findings
- Those monkeys with lesions of the hippocampus and parahippocampal cortex (HP) performed more poorly than
- Number of trials it takes for them to get it right is higher
- And monkeys with lesions of the hippocampus, parahippocampal cortex and perirhinal cortex (HPP) performed even more poorly
- Conclusion: Both the hippocampus and surrounding MTL critical for forming LTM
Does the tissue surrounding the hippocampus contribute to memory function?
yes, Both the hippocampus and surrounding MTL critical for forming LTM
-monkey studies
How is the MTL involved in encoding of declarative memories? How about retrieval of declarative memories?
- Hippocampus, parahippocampal cortex, and frontal cortex showed activity at encoding for items that the participant had seen, reported having seen, and correctly indicated the color
- Confirms that the hippocampus (and MTL) are important for forming new long-term memories
- Successfully encoded items, participants able to tell which item they had seen and in what color
What structure is involved in familiarity memory?
- anterior parts of the parahippocampal cortex (perirhinal and entorhinal cortex)
- perirhinal
Is the frontal cortex involved in memory? How?
- involved in STM and LTM
- Left frontal cortex = Episodic encoding OR Linguistic memory tasks (Words, linguistic verbal tasks)
- Right frontal cortex = Episodic retrieval OR Spatial memory tasks
- Ex: Outline of a frog when hearing or thinking of the word frog
Faces
What is the frontal aging hypothesis?
- states that normal age-related cognitive deficits are mediated by cognitive control deficits associated with prefrontal cortex (PFC) dysfunction
- Early memory deficits could be due to the fact that the frontal cortex is the last to mature but the first to deteriorate with age
Is parietal cortex involved in memory?
- Successful memory retrieval is also associated with activity in posterior parietal cortex
- Maintenance of info in working memory
- Integration of multiple types of information
- Attentional process of info entering working memory from senses or LTM
Where are memories stored in the brain?
-Memories are stored as distributed representations throughout the cortex, involving the areas in which they were perceived
○ Visual memories = stored in visual cortex
○ Auditory memories = stored in auditory cortex
-Motor = basal ganglia and cerebellum
What is consolidation? Describe 2 theories of consolidation.
- the process by which immediate memories are transformed into LTM
- Hippocampus is necessary for consolidation, storing them in specific areas of the brain
1. standard consolidation theory
2. multiple trace theory
standard consolidation theory
- Hippocampus is necessary for binding all of these memories together in the distributed part of the brain, BUT overtime hippocampus no longer necessary
- Older memories tend to be more preserved than newer memories
multiple trace theory
- For semantic memories = hippocampus is initially necessary, but overtime no longer is needed b/c a sense of familiarity takes over
- For episodic = hippocampus remains involve forever
Medial temporal lobe (MTL)
- Hippocampus = Encoding and recollection
- Parahippocampal, entorhinal, and perirhinal cortices = Recognition
frontal lobe
-STM and LTM, lateralized
parietal cortex
Multiple theories how parietal could be contributing to memory
