Sensation and Perception

• Sensation occurs when sensory receptors detect stimuli, convert energy into action potentials (transduction), and send them to the central nervous system

Sensory Receptors

• Specialized neurons responding to specific stimuli types
• Respond to pressure from the surrounding environment

Absolute Threshold

• Minimum stimulus energy needed for detection 50% of the time

Just Noticeable Difference

• Minimum stimulus difference required to detect a change

Perception

• How sensory information gets interpreted, organized, and experienced

Bottom-Up Processing

• Perceptions built from sensory input

Top-Down Processing

• Interpretation influenced by knowledge, experiences, and thoughts

Sensory Adaptation

• Reduced perception of constant stimuli over time

Inattentional Blindness

• Failure to notice visible things due to lack of attention

Signal Detection Theory

• Stimulus detection changes based on mental state

Frequency

• Number of waves passing a point in time (longer wavelengths = lower frequencies)

Amplitude

• Wave height from peak to trough

Vision: Anatomy of the Eye

• Key components include the pupil, iris, lens, retina, fovea, ganglion cells, optic nerve, blind spot, photoreceptors (rods and cones)

Optic Chiasm

• Where optic nerves from each eye merge, an X-shaped structure below the cerebral cortex

Visual Pathways

• "What" pathway aids object recognition
• "Where" pathway identifies stimulus location

Color Vision: Trichromatic Theory

• Colors derive from red, green, and blue (applies to the retina)

Opponent-Process Theory

• Color is coded in opposing pairs, some cells are excited by opponent colors (black-white, yellow-blue, green-red)

Afterimage

• Continuation of visual sensation after stimulus removal

Binocular Cues

• Rely on both eyes
• Disparity: each eye views the world from a slightly different angle

Monocular Cues

• Rely on one eye
• Linear perspective: parallel lines converge
• Interposition: overlapping objects

Color-blindness

• Deficiency in the way the colours are seen

Gestalt Principles of Visual Perception

• The whole differs from the sum of its parts

• Figure-ground: segment visual world into figure (focus) and ground (background)

• Proximity: group nearby things

• Similarity: group alike things

• Continuity: perceive smooth, continuous lines rather than broken ones

• Closure: fill in gaps to perceive complete objects

Audition: Anatomy of the Auditory System

• Outer: pinna and tympanic membrane
• Middle: three ossicles
• Inner: cochlea, basilar membrane, vestibular system

Auditory Transduction

• Sound waves vibrate the tympanic membrane, ossicles move, stapes press into the cochlea’s oval window
• Cochlear fluid moves, stimulating hair cells, which generates neural impulses that travel along the auditory nerve to the brain

Pitch Perception: Place Theory

• Different basilar membrane portions are sensitive to different frequencies (base = high, tip = low)

Temporal Theory

• Frequency is coded by sensory neuron activity level

Sound Localization

• Interaural level difference: sound intensity varies between ears due to head attenuation
• Timing difference: sound arrives at each ear at slightly different times

Hearing Loss

• Conductive: sound energy delivery to cochlea is impaired due to eardrum vibration or ossicle movement issues
• Sensorineural: failure to transmit neural signals from cochlea to brain
• Congenital: deafness from birth

Hearing Aids

• Amplify incoming sound waves

Taste

• Papillae: bumps on the tongue
• Taste buds: groupings of receptor cells with extensions protruding into a central pore (life cycle of 10 days to 2 weeks)

Taste Transduction (Gustation)

• Taste molecules bind to receptors, causing chemical changes and sending neural impulses to the brain

Supertasters

• Heightened sensitivity to bitter tastes suggesting genetic differences

Taste and Smell

• 80% of taste is due to smell

Olfaction

• Olfactory receptor cells: contain hair-like extensions that provide olfactory reception

Olfaction Transduction

• Odor molecules bind to receptors, signal gets sent to olfactory bulb, and finally to the limbic system and primary olfactory cortex

Pheromones

• Chemical messages sent from one individual to another

Touch

• Meissner’s corpuscles: respond to pressure and low-frequency vibrations
• Pacinian corpuscles: detect transient pressure and high-frequency vibrations
• Merkel’s discs: respond to light pressure
• Ruffini corpuscles: detect stretch

Thermoception

• Temperature perception

Nociception

• Sensory signal indicating potential harm and maybe pain

Vestibular Sense

• Maintains balance and body posture

Learning: Unlearned Behaviors

• Reflexes: triggered by a broad range of events
• Instincts: motor/neural reactions to stimulus, simple activity of specific body parts that involve primitive centers of the CNS

Associative Learning

• Organisms make connections between stimuli or events

Classical Conditioning

• Associate stimuli to anticipate events

• Unconditioned stimulus (UCS): elicits reflexive response (e.g., food)

• Unconditioned response (UCR): natural reaction to stimulus (e.g., salivation)

• Neutral stimulus (NS): doesn't elicit response initially; gets paired with UCS

• Conditioned stimulus (CS): elicits response after pairing with UCS

• Conditioned response (CR): behavior caused by CS

Higher-Order Conditioning

• Conditioned stimulus paired with a new neutral stimulus elicits conditioned response

Acquisition

• Initial learning period connecting neutral and unconditioned stimuli

Extinction

• Decrease in conditioned response when UCS no longer presented with CS

Spontaneous Recovery

• Return of extinguished conditioned response after a rest

Stimulus Discrimination

• Responding differently to similar stimuli

Stimulus Generalization

• Demonstrating conditioned response to similar stimuli

Habituation

• Learning not to respond to repeatedly presented stimuli

John Watson’s Little Albert Experiment

• Demonstrated stimulus-response reactions, pairing a neutral stimulus with a loud sound to induce fear

Operant Conditioning

• Associating behavior with consequences (B.F. Skinner)

B.F. Skinner and the Skinner Box

• Operant conditioning chamber containing a lever to release food

• Positive reinforcement: add something to increase behavior

• Positive punishment: add something to decrease behavior

• Negative reinforcement: remove something to increase behavior

• Negative punishment: remove something to decrease behavior

Shaping

• Rewarding successive approximations of target behavior

• Primary reinforcers: innate reinforcing qualities (e.g., food)

• Secondary reinforcers: learned value (e.g., praise, money)

Reinforcement Schedules

• Continuous: reinforcement every time
• Partial: reinforcement sometimes
• Fixed: reinforcement after a set amount of time or responses
• Ratio: based on number of responses between reinforcements (gambling)
• Variable: amount of time or responses varies between reinforcements (checking Instagram)
• Interval: based on time between reinforcements (paid by customer)

Cognitive Map

• Mental layout of environment

Latent Learning

• Learning occurs but not demonstrated until needed

Observational Learning (Modeling)

• Learning by imitating others

Social Learning Theory (Albert Bandura)

• Steps in modeling: attention, retention, reproduction, motivation

Vicarious Reinforcement

• Observer sees model rewarded, more likely to imitate

Vicarious Punishment

• Observer sees model punished, less likely to imitate

Bobo Doll Experiment

• Demonstrated how punished versus unpunished actions impact behavior

Thinking and Intelligence: Concepts

• Categories of linguistic information, images, ideas, or memories

Prototypes

• Best example of a concept

• Natural concepts: from direct or indirect experience

• Artificial concepts: defined by specific characteristics

Schema

• Mental construct of related concepts

• Role schema: assumptions based on roles

• Event schema (cognitive script): automatic behaviors that can make breaking habits difficult

Language

• A communication system using words and rules to transmit information

• Lexicon: words

• Grammar: rules

• Phoneme: basic sound unit

• Morpheme: smallest unit conveying meaning

• Syntax: word organization

• Semantics: meaning from morphemes/words

Language Development: Noam Chomsky

• Proposed biological basis for language acquisition

Critical Period

• Optimal language acquisition early in life

Problem-Solving Strategies

• Trial and error: try until solved
• Algorithm: step-by-step
• Heuristic: general framework for shortcuts
• Functional fixedness: inability to use objects beyond their designed purpose

Biases

• Anchoring: focus on one piece of information
• Confirmation: seek belief-confirming information
• Hindsight: believe events were predictable after they happened
• Representative: stereotype
• Availability: decision based on readily available examples

Intelligence: Classifying

• G: general factor of intelligence
• Crystallized: acquired knowledge and retrieval
• Fluid: seeing complex relationships

Sternberg’s Triarchic Theory

• Practical, creative, analytical

Gardner’s Multiple Intelligences

• Each person has at least eight intelligences

IQ Tests

• Measure intelligence quotient

• Stanford-Binet: early test for children

• Wechsler Adult Intelligence Scale: combines verbal and nonverbal subtests, most used

Flynn Effect

• Each generation has increased IQ

Bell Curve (Normal Distribution)

• Average IQ score is 100

Learning Disabilities

• Dysgraphia: writing difficulties
• Dyslexia: difficulty processing letters
• Dyscalculia: math difficulties
• ADHD: neurodevelopmental disorder (inattention, hyperactivity, impulsivity)

Creativity

• Producing novel, appropriate, and valued responses

Sternberg’s Investment Theory

• Intellectual skills, toying with ideas, stepping out of the box, supportive environment

• Convergent thinking: finding one best answer (IQ tests)

• Divergent thinking: finding multiple solutions Ideational Fluency: measuring diverse idea generation in response to a problem

Memory: Information Processing

• Encoding: putting information in memory
• Storage: retaining information
• Retrieval: getting information out

Encoding

• Labeling and coding information
• Automatic: encoding details like time and space
• Effortful: requires time and effort
• Semantic: encoding words and their meanings
• Visual: encoding images
• Acoustic: encoding sounds
• Self-Reference Effect: better memory for self-related information

Baddeley and Hitch Model

• Short-term memory has different forms

A-S Model

• Storage creates a permanent information record

• Sensory memory: brief storage of sensory events

• Short-term memory: processes incoming sensory memory

• Long-term memory: continuous information storage

Short-Term / Working Memory

• Temporary information retention and processing

Memory Consolidation

• Transferring from STM to LTM

Rehearsal

• Conscious repetition

Long-Term Memory

• Explicit: conscious recall

• Episodic: personal events

• Semantic: words, concepts

• Implicit: unconscious memories

• Procedural: how to do things

Retrieval

• Getting information out of storage

Memory Processes

• Recall: access without cues
• Recognition: identify previously learned information after encountering again
• Relearning: learning previously learned information

Brain Parts

• Amygdala: fear and emotional memories
• Hippocampus: explicit, recognition, and spatial memory which is used for navigation
• Cerebellum: procedural memories and classical conditioning
• Prefrontal cortex: semantic tasks

Neurotransmitters

• Repeated activity strengthens synaptic connections

Arousal Theory

• Strong emotions create stronger memories

Flashbulb Memory

• Record of atypical events with strong emotions

Amnesia

• Loss of long-term memory

• Retrograde: loss of past events记忆，无法回忆起创伤发生前的记忆

• Anterograde: inability to form new ones无法形成创伤后的记忆

Memory Construction

• Formulation of a new memory when remembering is attempted

Memory Reconstruction

• The act of remembering an old memory, which is not always accurate

Suggestibility

• False memories from external information

Eyewitness Misidentification

• Police procedures can alter memories

Misinformation Effect

• Misremembering events after exposure to incorrect information

Repressed and Recovered Memories

• Events can be repressed or falsely recalled

Forgetting

• Loss of Long Term Memory

Encoding Failure

• Memory was never encoded

Memory Errors (Schacter’s 7 Sins)

• Transience: temporary inaccessibility
• Absentmindedness: lapses in attention
• Blocking: temporary inaccessibility
• Misattribution: source confusion
• Suggestibility: false memories
• Bias: distorted memories
• Persistence: inability to forget undesirable memories

Storage Decay

• Unused memory fades

Interference

• Proactive: old interferes with new retroactive: new interferes with old

Ways to Enhance Memory

• Rehearsal: Repetition of information
• Chunking: organizing information into chunks
• Elaborative Rehearsal: Relating new information to stored memories
• Mnemonic Devices: Memory aids that organize information
• Use elaborative rehearsal
• Apply self-reference effect
• Keep studying to prevent decay
• Rehearse
• Be aware of inference
• Keep moving
• Get sleep
• Make use of mnemonic devices
• Quiz yourself