Introduction to Behavioral Neuroscience: Memory and the Hippocampus

Practice flashcards to review key concepts and details about behavioral neuroscience, specifically focusing on memory and the hippocampus.

What is Hebbian plasticity?

Hebbian plasticity is a theory that states if cell A persistently and repeatedly excites cell B, the efficacy of the synapse between them will increase.

Who proposed the theory of Hebbian plasticity?

Donald Hebb proposed the theory of Hebbian plasticity.

What happens to EPSP before LTP?

Briefly stimulating the presynaptic axon causes a mild depolarization (EPSP) in the postsynaptic cell.

What is the result of high-frequency stimulation in inducing LTP?

High-frequency stimulation produces repetitive EPSPs in the postsynaptic cell.

What occurs after inducing LTP?

Briefly stimulating the presynaptic axon causes a bigger EPSP in the postsynaptic cell.

What is the role of NMDA receptors in synaptic strengthening?

NMDA receptors help allow calcium to enter the postsynaptic cell, which is crucial for LTP.

What happens when glutamate binds to an AMPA receptor?

Binding of glutamate to an AMPA receptor opens a sodium channel, leading to depolarization/EPSP in the postsynaptic cell.

What blocks the NMDA receptor's calcium channel at resting membrane potential?

A magnesium ion blocks the NMDA receptor's calcium channel.

What does strong and persistent depolarization do to the magnesium ion in the NMDA receptor?

Strong and persistent depolarization repels the magnesium ion, allowing calcium to enter.

What are the two key changes induced by calcium entering the postsynaptic cell?

Calcium activates second messenger cascades that result in the transport of more AMPA receptors to the membrane and changes in gene expression.

Where is LTP particularly prevalent in the brain?

LTP is particularly prevalent in the hippocampus.

What is the suggested role of the hippocampus in memory formation?

The hippocampus is involved in short-term memory storage. It has a time-limited role in memory.

What happens to recent and remote memory when the hippocampus is inactivated?

Inactivation of the hippocampus disrupts recent memory retrieval but not remote memory retrieval. After sufficient time (30 days), the short-term memories in the hippocampus are converted into long-term memories elsewhere in the brain.

What does the two-stage model for memory formation propose?

It proposes that information is temporarily stored in the hippocampus during experience and gradually transferred to the cortex for long-term storage. (memory consolidation)

When does offline memory consolidation occur?

Offline memory consolidation occurs during times of no new experiences, such as during sleep.

What effect does sleep have on memory formation?

Sleep has been shown to benefit memory formation, and lack of sleep can slow down memory consolidation.

What are place cells in the hippocampus?

Place cells are neurons that respond to specific spatial locations and are involved in encoding trajectories in space.

What is hippocampal replay?

Hippocampal replay is the time-compressed re-occurrence of the same sequence of place-cell firing that occurs during sleep, reflecting recent experiences. A mechanism of memory consolidation, coordinated with cortical regions

What critical role does the hippocampus play in rodents vs humans?

The hippocampus is critical for episodic memory in humans but encodes spatial locations in rodents.

What evolutionary relationship might exist between episodic memory and navigation?

Episodic memory may share an evolutionary origin with navigation, suggesting a link between spatial encoding and memory.

What is the proposed connection between the hippocampus and the cortex?

The hippocampus is bidirectionally connected to the cortex, facilitating the transfer of memory information.This connection supports memory consolidation and retrieval, showcasing the interplay between memory formation and storage across brain regions.

What does the term 'pattern completion' refer to in memory?

Pattern completion refers to the reinstatement of a memory from partial cues.

Why is the hippocampus considered a 'fast learner'?

The hippocampus is termed a 'fast learner' due to its high plasticity and ability to quickly encode new information.