Psychology 101 H01 Exam 2

Bottom-up processing

Data-driven perception building from simple sensory features to complex representations; stimulus properties dominate.

Top-down processing

Expectation- and knowledge-driven interpretation; context, goals, and prior experience shape perception.

Transduction

Conversion of physical energy (e.g., light) into neural signals by sensory receptors.

Electromagnetic spectrum (vision)

Humans perceive ~400–700 nm; wavelength, amplitude, and purity map to color, brightness, saturation.

Wavelength (Hue)

Distance between light peaks; shorter ≈ blue, longer ≈ red.

Amplitude (Brightness)

Wave height; larger amplitudes are perceived as brighter.

Purity (Saturation)

Spectral “mixedness”; purer light appears more vivid, mixed looks washed-out.

Cornea

Clear, curved surface providing most refraction; first focusing stage.

Lens

Flexible focusing element; fine-tunes image on retina via ciliary muscle control.

Accommodation

Lens curvature change to keep images sharp (rounder for near, flatter for far).

Pupil

Adjustable opening regulating light entry; dilates in dim/arousal, constricts in bright light.

Nearsightedness (Myopia)

Eye too long/curved; focus before retina—distant objects blurry.

Farsightedness (Hyperopia)

Eye too short/flat; focus behind retina—near objects blurry.

Retina

Light-sensitive layer with photoreceptors and neural circuitry; starts visual processing.

Fovea

Central pit with highest cone density; best acuity and color detail.

Rods

Dim-light and peripheral vision; high sensitivity, no color, lower detail.

Cones

Daylight, color, and fine detail; densest in fovea; three wavelength classes.

Dark adaptation

Sensitivity increases in low light; rods recover slowly (up to ~20–30 min).

Light adaptation

Sensitivity decreases entering bright light; cones rapidly adjust as pigments bleach.

Receptive field

Retinal region influencing a neuron’s firing; center–surround organization enhances edges/contrast.

Blind spot

Optic disc lacks receptors; brain “fills in” missing information.

Visual pathways

Retina→optic nerve→optic chiasm→LGN/superior colliculus→primary visual cortex (V1).

Optic chiasm

Nasal retinal fibers cross; each hemisphere gets contralateral visual field.

Lateral geniculate nucleus (LGN)

Thalamic relay preserving retinotopy; layered streams to V1.

Superior colliculus

Midbrain center for rapid orienting eye/head movements and attention shifts.

Primary visual cortex (V1)

First cortical stage; maps visual field, extracts edges, orientation, spatial frequency.

Feature detectors

Neurons tuned to features (orientation, motion, length); simple/complex cells build contours/movement.

Ventral “what” pathway

V1→temporal; object identity, form, color; damage → visual agnosias.

Dorsal “where/how” pathway

V1→parietal; spatial location, motion, visuomotor control; damage → action deficits.

Consciousness

Awareness of self, environment, and internal mental activity; varies in level/content.

Mind–body problem

Relation of subjective experience to brain processes; dualism vs physicalism.

Circadian rhythms

~24-hour biological cycles (sleep, hormones, temperature); entrained by light.

Suprachiasmatic nucleus (SCN)

Hypothalamic master clock; receives retinal light input; times melatonin release.

Pineal gland

Secretes melatonin, especially in darkness; signals biological night.

Melatonin

Darkness-linked hormone promoting sleepiness and shifting circadian phase; light suppresses.

Sleep architecture

Repeating ~90-min cycles: N1→N2→N3 (early night more N3) and REM (late night more).

N1 (Stage 1)

Light sleep; theta activity; hypnagogic imagery and brief muscle jerks.

N2 (Stage 2)

Theta plus spindles and K-complexes; reduced responsiveness; largest share of sleep.

N3 (Slow-wave sleep)

Deepest NREM; delta waves; restorative functions, growth hormone release.

REM sleep

Rapid eyes, vivid dreams, atonia, “awake-like” EEG; memory and emotion processing; rebounds after deprivation.

Dream content

Recent concerns, strong emotions, sensorimotor themes; narrative bizarreness common.

Manifest content

Surface storyline of a dream.

Latent content

Symbolic/hidden meaning of a dream.

Problem-solving theory (dreams)

Dreams facilitate creative insight and reorganization of waking problems.

Mood-regulation view (dreams)

Dreams help process and integrate emotions, especially negative affect.

Activation–synthesis hypothesis

Brainstem activation during REM; cortex synthesizes signals into a narrative.

Insomnia

Trouble initiating/maintaining sleep or nonrestorative sleep with daytime impairment; CBT-I first-line.

Narcolepsy

Excessive daytime sleepiness; REM intrusions, possible cataplexy; often orexin/hypocretin deficit.

Sleep apnea

Repeated breathing interruptions (often obstructive); snoring, daytime sleepiness; CPAP helps.

Somnambulism (sleepwalking)

Ambulation from N3; unresponsive, amnesia; common in kids and with deprivation.

Hypnosis

Focused attention + increased suggestibility; used clinically for analgesia/habits/anxiety.

Hypnosis—role-playing

Socio-cognitive view: effects reflect expectations and social context.

Hypnosis—dissociation theory

state where consciousness is divided into different streams, allowing for heightened suggestibility in one stream while another stream remains aware; actions outside conscious control (“hidden observer”).

Meditation

Practices training attention/awareness; reduce stress and improve emotion regulation.

Focused-attention meditation

Sustained focus on a target (e.g., breath); stabilizes attention, reduces mind-wandering.

Open-monitoring (mindfulness)

Nonjudgmental awareness of present experience; boosts meta-awareness, emotional balance.

Psychoactive drugs

Substances altering CNS function (mood, perception, behavior).

Agonist

Increases neurotransmitter action (mimics, boosts release, blocks reuptake).

Antagonist

Decreases neurotransmitter action (blocks receptors or inhibits release).

Substance Use Disorder (SUD)

Maladaptive use with impaired control, social impairment, risky use; tolerance/withdrawal may occur.

Depressants

Lower CNS activity (alcohol, benzodiazepines); enhance GABA; sedation, impaired coordination.

Opioids

Analgesics at μ-opioid receptors (morphine, heroin, fentanyl); euphoria, respiratory depression, dependence risk.

Stimulants

Increase CNS activity (caffeine, nicotine, amphetamines, cocaine); ↑ dopamine/norepinephrine.

Hallucinogens

Alter perception/thought (LSD, psilocybin, mescaline); many act at 5-HT2A; sensory distortions.

Tolerance

Diminished effect with repeated use; higher doses needed; pharmacodynamic or metabolic.

Withdrawal

Opposing symptoms on stopping; reflects physiological adaptation.

Learning

Durable change in behavior/knowledge due to experience; associative and observational.

Classical conditioning

Neutral stimulus becomes CS after pairing with US; CS elicits CR resembling UR.

Unconditioned stimulus (US)

Naturally elicits a reflexive response.

Unconditioned response (UR)

Reflexive response to a US.

Conditioned stimulus (CS)

Previously neutral; after pairing with US, elicits learned response.

Conditioned response (CR)

Learned response to CS; typically weaker/smaller than UR.

Fear conditioning

CS paired with aversive US → conditioned fear; can generalize; basis for phobias.

Evaluative conditioning

Pairing with positive/negative stimuli shifts liking/attitudes (common in ads).

Acquisition (classical)

CS–US pairing strengthens CS→CR; best when CS slightly precedes US. (ex: pavlov dog bell ringing (CS) leading to salivation (CR) when food (US) is presented.)

Extinction (classical)

(classical conditioning) conditioned response (CR) weakens when conditioned stimulus (CS) is repeatedly presented without the unconditioned stimulus (US), breaking down the association btw CS and US

Spontaneous recovery

Extinguished CR reappears after rest; original learning persists.

Generalization (classical)

CR to stimuli similar to CS; more similar → stronger response.

Discrimination (classical)

CR to CS but not similar stimuli after nonreinforced exposure to them.

Operant conditioning

Behavior shaped by consequences; reinforcement increases, punishment decreases behavior.

Law of Effect

Satisfying outcomes strengthen behavior; discomfort weakens it.

Skinner box

Controlled chamber measuring responses under contingencies; lever/key and outcome delivery.

Cumulative recorder

Graphs cumulative responses; slope indexes response rate.

Reinforcement

Consequence that increases behavior (adds desirable or removes aversive).

Punishment

Consequence that decreases behavior (adds aversive or removes desirable).

Positive reinforcement

Add desirable stimulus after behavior → behavior increases.

Negative reinforcement

Remove aversive stimulus after behavior → behavior increases (not punishment).

Positive punishment

Add aversive outcome after behavior → behavior decreases.

Negative punishment

Remove desirable outcome → behavior decreases.

Acquisition (operant)

Behavior strengthens as it reliably produces reinforcement.

Shaping

Reinforce successive approximations toward a target behavior.

Extinction (operant)

Behavior declines when reinforcement is discontinued.

Resistance to extinction

Persistence after stopping reinforcement; stronger after intermittent schedules.

Discriminative stimulus

Cue signaling whether a response will be reinforced or punished.

Primary reinforcer

Innately reinforcing (food, warmth); linked to biological needs.

Secondary reinforcer

Gains value via association (money, grades).

Schedules of reinforcement

Rules for delivering reinforcement; shape rates and persistence.

Fixed ratio (FR)

Reinforce after set number of responses; high rate with brief pause.

Variable ratio (VR)

Reinforce after varying response counts; highest steady rates, very persistent.

Fixed interval (FI)

Reinforce first response after fixed time; “scalloped” bursts near interval end.