Neurobiology of Sleep and Memory Processes

Flashcards covering key terms and definitions related to sleep neurobiology and memory processes.

Circadian Rhythm

Our body’s internal clock that follows a roughly 24-hour cycle.

Sleep Pressure

Builds up with adenosine during wakefulness, creating a drive for sleep.

Adenosine

A neurotransmitter that creates sleep drive and slows down neuronal activity.

Caffeine

An adenosine receptor antagonist that blocks the effects of adenosine.

Melatonin

A hormone produced by the pineal gland in response to darkness that regulates sleep.

Pineal Gland

The gland that regulates the body's circadian rhythm and produces melatonin.

Suprachiasmatic Nucleus (SCN)

Part of the hypothalamus that controls circadian rhythms.

EEG

A neuroimaging method that records the brain's electrical activity.

Alpha Waves

Relaxed, awake 

Beta Waves

Alert, active thinking

Theta Waves 

Light sleep, drowsy 

Delta Waves

Deep sleep (slow waves)

NREM Sleep

Non-Rapid Eye Movement sleep that includes Stages 1-3.

REM Sleep

Rapid Eye Movement sleep characterized by vivid dreams and muscle atonia.

Stage 1

Light sleep (theta waves) 

Stage 2

Sleep spindles, K-complexes

Stage 3

Deep sleep (delta waves)

Sleep Architecture

The structure of sleep cycles including NREM and REM, cycling approximately every 90 minutes.

Hippocampal-Neocortical Dialog Model

A model that posits the hippocampus replays experiences during slow-wave sleep to transfer to cortex.

Dreams

Mental experiences during sleep that can help process emotions and enhance creativity.

Freud's Theory of Dreaming

Dreams express unconscious desires

Manifest content 

What you remember from the dream

Latent content 

Hidden meaning behind the dream 

Activation-Synthesis Model

Dreams are the brain’s attempt to make sense of random neural activity

Encoding

The process of transforming information into a form that can be stored.

Storage 

Maintaining information over time 

Retrieval

Brining stored information into conscious awareness 

Semantic Encoding

Meaning-based (deep processing → best memory)

Visual Imagery Encoding

Forming mental pictures to aid memory

Organizational Encoding

Structuring info (categories, hierarchies)

Encoding-Specificity Principle

Retrieval cues work best when similar to original context

State-Dependent Retrieval

When retrieval cues are reliant on internal states like mood or physiology.

Sperling’s Study

An experiment demonstrating sensory memory through improved recall with partial-report cues.

Explicit Memory

Conscious recall of information, including episodic and semantic memory.

Implicit Memory

Unconscious skills and conditioning that do not require conscious thought.

Amnesia

Memory loss that can be retrograde (loss of old memories) or anterograde (inability to form new memories).

Behaviorism 

Focuses on obserable behaviors and how they’re learned 

Classical Conditioning

Learning by associating two stimuli

Operant Conditioning

Learning through consequences, where behaviors are influenced by rewards or punishments.

Unconditioned Stimulus (US)

A stimulus that naturally produces a response without prior conditioning.

Unconditioned Response (UR)

Automatic response to an unconditioned stimulus.

Neutral Stimulus (CS)

A stimulus that initially produces no specific response but can become conditioned to elicit a response through association with an unconditioned stimulus.

Conditioned Stimulus (CS)

A previously neutral stimulus that, after being paired with an unconditioned stimulus, eventually elicits a conditioned response.

Extinction

The process by which a conditioned response diminishes or disappears when a conditioned stimulus is presented without the unconditioned stimulus.

Spontaneous Recovery

The reappearance of a conditioned response after a period of absence, following extinction.

Second-Order Conditioning

A learned association where a conditioned stimulus is paired with a new neutral stimulus to elicit a conditioned response.

Generalization 

The tendency for a conditioned response to be elicited by stimuli similar to the conditioned stimulus, leading to similar behaviors.

Contiguity

The principle that states that for learning to occur, events must occur close together in time, facilitating associations between stimuli.

Contingency 

The relationship between a behavior and its consequences, where the likelihood of a conditioned response is influenced by the presence of a specific unconditioned stimulus following the conditioned stimulus.

Rescorla & Wagner

Learning depends on prediction

Thorndike’s Law of Effect 

Behaviors followed by satisfying outcomes are more likely to be repeated; unpleasant outcomes make behavior less likely

Intermittent Reinforcement Effect 

Behaviors on partial schedules are more resistant to extinction 

Fixed-Interval

Reinforcement after set time

Variable Interval

Reinforcement after varying time 

Fixed Ratio 

Reinforcement after set number of responses 

Variable Ratio 

Reinforcement after unpredictable number of responses 

Latent Learning

Learning that occurs without immediate reinforcement, demonstrated by cognitive maps.

Cognative Maps

Mental representation of environment → learning involves expectations 

Taste Aversion and Biological Preparedness

Some associations are learned faster due to evolutionary adaptation

Observational Learning

Learning that occurs through observing others, exemplified by Bandura’s Bobo Doll study.

Implicit Learning

Learning that happens without conscious awareness, often related to language patterns.

Neural Correlates

Basal ganglia and cerebellum for procedural skills; explicit learning relies on hippocampus and frontal lobes

Implicit Association Test (IAT)

Measures unconscious bias through reaction times to word pairings