Lecture 4- Learning & Memory 2

Question 1

What is nondeclarative, or procedural, memory, and what kinds of information fall under this category?

Answer 1

Nondeclarative, or procedural, memory includes unconsciously acquired and retrieved information, such as motor skills, classical conditioning, priming effects, and puzzle solving skills.

Question 1

Phylogenetic Memory

Answer 1

Iherited genetic knowledge and instincts passed down through generations of a species.

Question 2

Priming Effect

Answer 2

exposure to one stimulus influences the response to another stimulus, often leading to increased accessibility or processing speed of related information.

Question 3

Skinner Box

Answer 3

The most common method for studying operant conditioning, involved placing a rodent in a controlled environment to study how they learn behaviors through rewards and punishments

Question 4

A clinical case study of H.M.’s brain after a bilateral medial temporal lobe resection (removal of amygdala, uncus, hippocampal gryus, anterior two-third of hippocampus) revealed impairment to what type of memory?
A.) anterograde
B.) retrograde
C.) nondeclarative
D.) Both A and B

Answer 4

A.) anterograde; inability to form new memories after an event or injury, while past memories remain intact.

Question 5

A clinical case study of K.C.’s brain after bilateral hippocampal and parahippocampal damage revealed impairment to what type of memory?
A.) anterograde
B.) retrograde
C.) nondeclarative
D.) Both A and B

Answer 5

D) Anterograde and retrograde. He was unable to retrieve personal memories from his past (retrograde amnesia) and also unable to form new episodic memories (anterograde amnesia) after his accident. However, his ability to form new semantic memories and learn new skills was preserved.

Question 6

What is the role of the limbic circle in memory?

Answer 6

The limbic circle is a neural circuit that connects various brain centers, including the hippocampus, amygdala, and thalamus, crucial for forming declarative memories.

Question 7

What function does the fornix serve in the limbic system?

Answer 7

The fornix is a fiber tract that carries information from the hippocampus to the mammillary bodies, facilitating memory formation.

Question 8

What is a characteristic of short-term memory in terms of stability?

Answer 8

Short-term memory is labile, meaning it is sensitive to disruption.

Question 9

What are the hallmarks of Alzheimer’s disease in the brain?

Answer 9

Neurofibrillary tangles and amyloid plaques, particularly dense in the hippocampus, are hallmarks of Alzheimer’s disease, indicating neuron degradation​​.

Question 10

How does the Morris water maze demonstrate the role of the hippocampus in memory?

Answer 10

The Morris water maze shows that the hippocampus is essential for spatial learning and memory in rodents, as damage to this area impairs the ability to navigate the maze​​

Question 11

How is the protein Arc involved in synaptic plasticity?

Answer 11

Arc binds to the cytoskeletal protein actin in dendritic spines, playing a key role in synaptic plasticity and memory processes like long-term potentiation (LTP)​​.

Question 12

Does short-term memory require new RNA or protein synthesis?

Answer 12

No, short-term memory does not require new RNA or protein synthesis.

Question 13

What does it mean for long-term memory to be consolidated?

Answer 13

Consolidation means that long-term memory becomes insensitive to disruption over time.

Question 14

Does long-term memory formation involve new RNA or protein synthesis?

Answer 14

Yes, long-term memory formation requires new RNA or protein synthesis

Question 15

Amygdala Functions

Answer 15

1)Emotional memory
2) Motor Response
3) Decision Making
4) Social Cognition
5) Awareness
6) Salience Detection

Question 16

Where is the hippocampus located in relation to the lateral ventricle?

Answer 16

The hippocampus is located on the medial wall of the lateral ventricle.

Question 17

Which nerve fibers are located proximal to the mammillary body?

Answer 17

The optic nerve fibers are located proximal to the mammillary body.

Question 18

Pathway of the Trisynaptic Circuit

Answer 18

1. Granule cells in dentate gyrus send axons (mossy fibers) to excite CA3 pyramidal cells.
2. CA3 pyramidal cells send axons (Schaffer collaterals) to contact neurons in CA1.
3. CA1 pyramidal cells continue relaying information to other limbic system and cortical regions, facilitating information processing within the hippocampal circuitry.

Question 19

Explain the Hippocampus Circuity

Answer 19

Information enters the hippocampus from the entorhinal cortex, which includes the medial and lateral entorhinal cortex.

The subiculum acts as a relay station, forwarding information from the entorhinal cortex to the hippocampus proper.

Information from the dentate gyrus travels to the CA3 region through mossy fibers and then to CA1 via Schaffer collaterals.

Processed information exits the hippocampus through a structure called the fimbria of the fornix and connects with other brain regions in the limbic system, such as the amygdala.

Question 20

Where does the hippocampus receive its information from?

Answer 20

The hippocampus receives its information from the entorhinal cortex, including both the medial and lateral entorhinal cortex.

Question 21

What role does the subiculum play in the hippocampal circuitry?

Answer 21

The subiculum acts as a relay station, sending information from the entorhinal cortex to the rest of the hippocampus.

Question 22

How is information transmitted within the hippocampus?

Answer 22

Information is transmitted from the dentate gyrus to the CA3 region via mossy fibers and then to CA1 via Schaffer collaterals.

Question 23

How does information processed in the hippocampus reach other brain regions?

Answer 23

Processed information exits the hippocampus through the fimbria of the fornix and links to other regions in the limbic system, such as the amygdala.

Question 24

Which proteins are influenced by CREB's transcriptional activity?

Answer 24

CREB influences the transcription of proteins like brain-derived neurotrophic factors (BDNF) and activity-regulated cytoskeleton-associated protein (Arc).

Question 25

How do Fos and c-Fos function as markers in memory research?

Answer 25

Fos and c-Fos serve as early indicators of neuronal activity during memory formation and modification.

Question 26

When are immediate early genes like Fos and c-Fos typically activated?

Answer 26

Immediate early genes are activated shortly after synaptic activity, indicating the start of new memory encoding or alteration.

Question 27

Describe the relationship between kinase pathways and memory mechanisms.

Answer 27

Kinase pathways, through phosphorylation, activate CREB and other transcription factors, initiating gene expression linked to memory formation.

Question 28

What molecular changes occur in neurons during learning?

Answer 28

Learning triggers kinase pathways that lead to gene expression and synaptic changes in neurons, forming the basis of memory encoding.

Question 29

What is the function of Arc protein in dendritic spines?

Answer 29

Arc binds to F-actin, a structural protein of dendritic spines, helping to helps stabilize and transport proteins in dendritic spines

Question 30

How does Arc influence synaptic changes associated with learning?

Answer 30

Arc controls the removal and addition of AMPA receptors at synapses, leading to weakening (LTD) or strengthening (LTP) of synaptic connections.

Question 31

What is the Morris water maze test designed to evaluate in rodents?

Answer 31

The Morris water maze test evaluates spatial learning and memory, requiring rodents to locate a hidden platform in a tank using environmental cues.

Question 32

What effect do hippocampal lesions have on rodents in the Morris water maze?

Answer 32

Rodents with hippocampal lesions show impaired learning and memory as they fail to remember the platform's location, indicating the hippocampus's critical role in this process.

Question 33

Lesions of varying size and location were made in rat brains either before or after the animals had learned to run mazes of varying complexity. Which of the following conclusions can be made based on the results of the experiment?

Answer 33

A.) The amount of tissue destroyed was proportional to learning reduction B.) Tissue location was inconsequential in learning reduction (it didn't matter where the damage occured, the impact was similar) C.) lesions were more likely to reduce performance for complex tasks

Question 34

What type of memories are included in declarative memory?

Answer 34

Declarative memory includes daily episodes, words and their meanings, and history.

Question 35

Difference between declarative and non-declarative memory

Answer 35

Declarative memory involves information that can be consciously recalled, such as facts and events, while nondeclarative memory involves skills and actions that are performed without conscious awareness.

Question 36

SA: What lines of evidence support the proposal that declarative memory and procedural memory involve different brain mechanisms?

Answer 36

Evidence from patients like H.M., N.A., and R.B., who had damage to their hippocampus, had deficits in declarative memory but could still learn new skills (procedural memory). This suggests different parts of the brain handle these types of memory.

Question 37

SA: What has patient H.M. taught us about human memory?

Answer 37

Patient H.M. had damage to his medial temporal lobe. After surgery, he couldn't form short-term memories, but he retained the ability to recall information and events from before his surgery, so his long-term memory was intact. He could also learn new skills like playing the piano, suggesting long-term and procedural memory are managed by brain regions other than the medial temporal lobe.

Question 38

SA: What approaches are used to assess hippocampal involvement in memory consolidation?

Answer 38

The role of the hippocampus in memory formation can be assessed in different ways. 1. Examining patients that have hippocampus damage or using fMRI to scan healthy subjects can give insight into hippocampal function. 2. Additionally, lesion studies in laboratory animals allow observation of the effects of damage to specific locations

Question 39

SA:Which evidence suggests that short-term and long-term memory involve different brain mechanisms?

Answer 39

In addiiton to retaining their procedural memory, H.M., N.A., and R.B. retained old memories formed prior to their injury but struggled to form new ones, showing only anterograde amnesia. Hippocampal damage impacts short-term, not long-term memory storage. 2. Additionally loss of cortical regions and techniques like electroconvulsive therapy can cause retrograde amnesia, suggesting long-term memory storage happens in the cortex.

Question 40

SA: What are the neural and behavioral symptoms of Alzheimer’s disease? Briefly summarize the current view on the causes of Alzheimer’s disease

Answer 40

Neural symptoms: Presence of neurofibrillary tangles, amyloid-beta plaques, and a loss of neurons Behavioural Symptoms: Memory problems, language deficits, spatial issues, and personality changes. Cause: The cause is unclear, but genetic mutations like in amyloid precursor protein, presenilin 1, and presenilin 2 are linked to early-onset Alzheimer's. The e4 allele of the ApoE gene raises late-onset Alzheimer's risk.

Question 41

SA: What changes occur in the brain as humans age?

Answer 41

As humans age, the brain shrinks, likely due to lost connections rather than neuron loss. These changes may lead to declining memory function that occurs with age