Lecture 5

Question 1

What are memory traces, and how do they relate to the binding of memories?

Answer 1

Memory traces refer to neural representations encoding memories in the brain. Binding involves integrating different aspects of a memory, such as sensory details and emotions, into a unified whole.

Question 2

Explain the multi-storage theory of memory in a concise manner, outlining its main components and how it accounts for memory processing stages.

Answer 2

Multi-Storage Theory: Memory is composed of distinct storage systems, each serving a specific role in the memory process.
Sensory Memory:
Brief duration (milliseconds to seconds).
Registers sensory input (e.g., visual or auditory stimuli).
Short-Term Memory (STM):
Limited capacity (usually around 7 items).
Short-lived (seconds to minutes without rehearsal).
Selectively attends to and processes information from sensory memory.
Long-Term Memory (LTM):
Virtually unlimited storage capacity.
Memories can last a lifetime.
Information is consolidated and stored for future retrieval.

Question 3

Explain Hebb’s theory of memory and its significance.

Answer 3

Hebb’s theory states that neurons strengthen their connections when repeatedly activated together. It’s crucial for forming memory traces and synaptic plasticity.

Question 4

What is reverberating neural activity in memory, and how does it help in storing and recalling information?

Answer 4

Reverberating neural activity is when neurons continue to fire in a closed-loop circuit, aiding memory by maintaining and strengthening memory traces for better retention and recall.

Question 5

Define the concept of consolidation in the context of memory. Explain its significance in the formation and long-term storage of memories.

Answer 5

Consolidation in memory refers to the process by which newly acquired information is gradually stabilized, strengthened, and integrated into long-term memory. It involves the transformation of fragile, initially labile memory traces into more permanent and durable forms, allowing for better retention and recall of the information over time.

Question 6

What is reactivation concerning memory, and why is it important in the memory retrieval process?

Answer 6

Reactivation in memory refers to the process of recalling or re-experiencing previously encoded information. It plays a crucial role in memory retrieval by allowing individuals to access stored memories, bringing them from long-term storage to conscious awareness. Reactivation is a key step in recalling facts, events, or experiences from one’s past.

Question 7

According to Hebb – When does strengthening occur?

Answer 7

When the postsynaptic and the presynaptic cell fire together,
the connection between them is strengthened

cells that fire together, wire together

Question 8

What is neuroplasticity, and how does it relate to changes in synaptic strength?

Answer 8

Neuroplasticity is the brain’s ability to change by forming new neural connections. Changes in synaptic strength, as seen in LTP, are fundamental to neuroplasticity, allowing the brain to adapt to new experiences.

Question 10

Describe what long-term potentiation (LTP) is and its significance in memory formation.

Answer 10

LTP is the strengthening of synaptic connections following high-frequency stimulation. It’s a key cellular mechanism underlying learning and memory

Question 11

Differentiate between short-term memory and long-term memory. How does synaptic strengthening play a role in both?

Answer 11

Short-term memory is temporary, relying on sustained neuronal activation. Long-term memory involves consolidating memories over time. Synaptic strengthening makes it easier to reactivate memory traces, contributing to long-term memory.

Question 12

Define NMDA and its role in neural function.

Answer 12

NMDA (N-Methyl-D-Aspartate) is a type of glutamate receptor that plays a pivotal role in synaptic plasticity and learning. It is essential for long-term potentiation (LTP), a process associated with the strengthening of synaptic connections during memory formation and storage in the brain.

Question 13

Explain the role of NMDA receptors in LTP.

Answer 13

NMDA receptors play a critical role in synaptic strength changes during LTP. They require both pre-synaptic and post-synaptic neuron activation to open, contributing to Hebbian plasticity.

Question 14

What is the Morris water maze, and how does AP5 impact it?

Answer 14

The Morris water maze is used to study spatial learning and memory in animals. AP5, an NMDA receptor antagonist, interferes with learning and memory processes in animals tested in the Morris water maze.

Question 15

How does ZIP affect established memories, and what does this reveal about memory consolidation?

Answer 15

ZIP disrupts established memories in laboratory rats, indicating that manipulating synaptic strength can impact memory recall. This highlights the role of LTP in memory consolidation.

Question 16

Describe what AP5 is and its specific role in neural function. How does it impact processes like memory and learning?

Answer 16

AP5 (D-AP5 or D-2-Amino-5-phosphonovaleric acid) is an antagonist of NMDA receptors. It interferes with the normal functioning of NMDA receptors, disrupting processes like long-term potentiation (LTP) crucial for memory formation. Explain its significance in the study of memory and neural plasticit

Question 17

Summarize the basic method of the Morris water maze test, highlighting its primary components and purpose in memory research.

Answer 17

The Morris water maze is a widely used test in memory research. It involves placing a subject in a large tank of warm water and evaluating its ability to locate a submerged platform. The main objective is to assess spatial learning and memory capabilities in animals.

Question 18

Provide a concise overview of Davis et al.’s 1992 study regarding the role of blocking LTP in memory formation.

Answer 18

Davis et al. (1992) conducted an experiment where they blocked Long-Term Potentiation (LTP) and examined its effect on memory formation. Their findings shed light on the relationship between LTP and memory processes.

Question 19

Explain what ZIP (Zeta-Inhibitory Peptide) is and its relevance in memory research.

Answer 19

ZIP, or Zeta-Inhibitory Peptide, is a molecule that inhibits the activity of protein kinase M zeta (PKMζ), which is believed to play a critical role in maintaining the strength of synapses associated with long-term memory. Its significance lies in its potential to disrupt established memories when applied to the brain, providing insights into memory consolidation and retrieval processes.

Question 20

Provide a concise overview of the method used in the study conducted by Pastalkova et al. (2006) concerning ZIP’s effect on established memories.

Answer 20

Pastalkova et al. (2006) used a method involving the application of ZIP (Zeta-Inhibitory Peptide) to the brains of experimental animals. The researchers selectively reactivated specific memories and observed the temporary erasure of these memories following ZIP application. This method helped investigate the role of ZIP in disrupting established memories.

Question 21

Describe the specific function that the visual cortex V4 is primarily responsible for in visual processing.

Answer 21

Visual cortex V4 is primarily responsible for processing color and color perception in the visual system.

Question 22

Explain the primary function of the visual cortex V5 in the context of visual processing.

Answer 22

The visual cortex V5, also known as the medial temporal (MT) area, is primarily responsible for processing motion and motion perception in the visual system.

Question 23

Define the term “akinetopsia” and describe its characteristics and effects on visual perception.

Answer 23

Akinetopsia is a neurological disorder characterized by the inability to perceive motion. Individuals with akinetopsia may see the world as a series of static, disjointed snapshots rather than a continuous flow of motion

Question 24

What did patient M.P have?

Answer 24

Bi-Lateral lesions of V5, Akinetopsia

Question 25

Describe direction and speed tuning in visual cortex V5 and their significance in visual perception.

Answer 25

Direction tuning in V5 involves neurons specialized in responding to specific motion directions, while speed tuning relates to neurons sensitive to motion speed. These features enable the brain to accurately process and interpret visual motion.

Question 26

What is “looming” in vision, and why is it important for visual perception?

Answer 26

Looming in vision refers to the visual sensation of an object approaching or getting closer, often accompanied by its apparent expansion in the visual field. It is important for assessing the proximity and potential threat of objects in the environment, contributing to our ability to perceive depth and motion accurately.

Question 27

Why is it important that the brain processes visual information through parallel pathways when it comes to perceiving objects?

Answer 27

Processing visual information through parallel pathways means the brain can analyze different aspects of an object (like its color, shape, and movement) at the same time. This helps us quickly and accurately recognize objects in our environment.

Question 28

Explain the “binding problem”

Answer 28

The “binding problem” refers to how our brain combines different pieces of information from our senses (like color, shape, and motion) to create a single, unified perception of an object. It’s like putting together a puzzle where each piece represents a different aspect of what we see, and the brain has to figure out how they all fit together to form a complete picture.

Question 29

hat is “temporal binding” in neural processing, and how does it help coordinate the representation of objects in the brain?

Answer 29

Temporal binding is when brain cells fire in sync to create cell assemblies, collectively representing an object at a specific moment. This coordination helps link different features of the object together for a unified perception.