Psychology of Memory & Learning exam 1

Intro to Memory & Learning

• Hermann Ebbinghaus pioneered scientific memory study methods
• He invented nonsense syllables to measure "pure memory"
• Ebbinghaus's methods removed prior knowledge to isolate learning processes

Forgetting Curve

• The forgetting curve depicts memory decline over time
• Initial forgetting is rapid, then slows down
• Reinforcement and repetition are crucial for memory retention

Single-Trace vs. Dual-Trace Theories

• Single-trace theory: Memory strength gradually declines
• Dual-trace theory: Short-term and long-term memory traces exist
• Short-term traces fade quickly, long-term traces decay more slowly

Ribot's Law

• Older memories are more resistant to brain damage than newer ones
• This explains why individuals with brain disorders often forget recent memories first

Korsakoff's Syndrome

• Caused by thiamine deficiency, often due to alcoholism
• Symptoms include anterograde amnesia (inability to form new memories), retrograde amnesia (loss of past memories), and confabulation (filling memory gaps with false information)

William James' Stages of Memory

• James differentiated between immediate sensory memory, primary memory (short-term), and secondary memory (long-term)
• Different stages exist for initial and sustained memory retention

Neuron Doctrine & Synaptic Plasticity

• Neuron doctrine: Brain comprises individual nerve cells (neurons) separated by membranes
• Synaptic plasticity hypothesis: Synaptic connections strengthen with experience, forming the basis of learning and memory

Rosenzweig & Bennett Experiment

• Enriched environments increase synaptic connections in the brain, supporting the synaptic plasticity hypothesis

Classical Conditioning (Pavlov)

• Associative learning where a neutral stimulus is paired with an unconditioned stimulus, triggering a conditioned response
• Pavlov's dogs demonstrated this through the pairing of bell and food

Instrumental Conditioning (Thorndike & Skinner)

• Instrumental learning occurs via consequences of behavior
• Thorndike's law of effect: Behaviors with positive outcomes are reinforced; negative outcomes weaken behavior
• Skinner used operant conditioning, reinforcement, and punishment to study behavior

Positive & Negative Reinforcement

• Positive reinforcement: Adding a desirable stimulus to increase behavior
• Negative reinforcement: Removing an undesirable stimulus to increase behavior

Application of Memory Research in Education

• Spaced repetition improves learning
• Active recall techniques (e.g., flashcards) enhance retention
• Mnemonics aid memorization

Memory Research in Legal Field

• Memory research helps understand eyewitness reliability
• It identifies false memories in interrogation settings
• This affects jury decision-making processes and legal procedures

Long-Term Potentiation (LTP)

• LTP: Strengthening of synaptic connections due to repeated stimulation
• High-frequency stimulation induces LTP by enhancing synaptic responses
• LTP lasts for minutes to hours

Recording Field Potentials

• Neuronal activity is measured using electrodes near neuronal populations
• The amplitude of recorded electrical signals corresponds to synaptic strength

Synapse Components

• Synapse structure: Presynaptic terminal, synaptic cleft, postsynaptic membrane
• Postsynaptic density (PSD) includes receptors, scaffolding proteins, and signaling proteins

Role of Scaffolding Proteins

• They organize receptors and signaling molecules in the postsynaptic density, affecting synaptic strength and plasticity

First and Second Messengers

• First messengers: external stimuli like neurotransmitters
• Second messengers: intracellular molecules that amplify the first messenger signal, including calcium and cAMP

Protein Kinases and Signal Transduction

• Protein kinases phosphorylate proteins, altering their functions
• Kinases impact signal transduction pathways and learning, e.g., CaMKII strengthens synaptic connections during LTP

LTP Intensity and Duration

• Stronger stimulation leads to longer-lasting LTP
• Greater calcium influx induces more prominent synaptic modifications

Three Processes Contributing to LTP

• Induction: Initiating stimulation such as tetanus
• Expression: Synaptic strength enhancement
• Maintenance: Long-term structural changes

NMDA and AMPA Receptors

• NMDA receptors require glutamate and depolarization to activate
• Calcium influx through NMDA receptors affects plasticity
• AMPA receptors trigger faster synaptic transmission when activated by glutamate

Actin Filaments & Synapses

• Actin filaments stabilize and reshape synapses during LTP, strengthening dendritic spines for lasting memory storage

Calcium's Role in LTP

• Calcium triggers second messengers like CaMKII
• Calcium activates kinases that increase synaptic strength
• Calcium supports gene expression for long-term synaptic changes

Types of Memory

• Sensory memory: Brief storage of sensory information (e.g., iconic, echoic)
• Short-term memory: Temporary storage of information for immediate use (limited capacity, ~15-30 seconds)
• Long-term memory: Persistent storage of information (theoretically infinite capacity)

Short-Term Memory Capacity

• Miller's Law: 7± 2 items (chunks of information)
• Cowan's revision proposes a narrower capacity

Explicit vs. Implicit Memory

• Explicit Memory: Conscious recall of facts and events (e.g., episodic, semantic)
• Implicit Memory: Unconscious knowledge and skills (e.g., procedural memory)

Explicit & Implicit Brain Regions

• Explicit memory relies on hippocampus, cortex, and thalamus
• Implicit memory relies on basal ganglia, cerebellum, and amygdala

Hippocampus and Memory

• Hippocampus consolidates short-term into long-term memories
• Damage to the hippocampus impairs the formation of new long-term memories

Episodic vs. Semantic Memory

• Episodic memory: Personal experiences and events
• Semantic memory: General facts and knowledge

Procedural Memory

• Implicit memory that encompasses motor skills and learned behaviors

Non-Associative Learning Types

• Habituation: decreased response to repeated stimuli
• Sensitization: increased response to repeated stimuli
• Latent learning: Learning without immediate use
• Insight learning: sudden realization

Multiple Memory Systems Theory

• Different types of memory depend on distinct brain regions
• There is evidence supporting the idea that explicit and implicit memories function distinctly