Plain-language explanation.
Perception bridges the physical world and conscious experience — studying how patterns of sensory energy become the sights, sounds, and sensations we experience.
Core concepts and standard treatment.
Core perception covers psychophysics (Fechner; Weber's law — JND; Stevens power law; signal detection theory — d-prime, criterion, ROC curve; absolute vs difference thresholds; sensory adaptation), vision (rods and cones — fovea; phototransduction; opponent process — Hering; trichromatic — Young-Helmholtz; contrast sensitivity function; Marr's three stages — primal sketch, 2.5D, 3D model; face recognition — fusiform face area — prosopagnosia; dorsal and ventral streams — what and where), audition (basilar membrane — place theory — Helmholtz; frequency theory — Rutherford; volley theory; auditory cortex — tonotopic; binaural hearing — ILD, ITD; categorical speech perception — McGurk effect; auditory stream segregation — Bregman), and multisensory integration (rubber hand illusion — Botvinick and Cohen; McGurk effect; temporal binding; ventriloquist effect; sensory substitution — Bach-y-Rita tactile-visual — BrainPort).
Deeper theory, debates and edge cases.
Advanced perception covers predictive coding (Helmholtz unconscious inference; Bayesian brain — Knill and Pouget; predictive processing — Clark and Friston — precision-weighted prediction errors; active inference — motor control as prediction error minimisation; explaining illusions via priors — hollow face, Kanizsa triangle), visual consciousness and attention (feature integration — Treisman — pre-attentive vs attentive; Posner spatial cueing; binocular rivalry — NCC; Libet experiment — readiness potential; backward masking — subliminal priming), and applied perception (Gibson — affordances — direct perception — optic flow; wayfinding — landmarks, survey, route knowledge; gate control theory of pain — Melzack and Wall; descending pain modulation; placebo analgesia; Proust phenomenon — smell and episodic memory; olfaction and Alzheimer's).
How it is applied in practice.
At the perception researcher and human factors psychologist level, practitioners contribute to Perception and Vision Research; lead applied research (Wellcome Centre FMRIB Oxford; MRC CBSU Cambridge; Unilever consumer neuroscience — fragrance perception); advise on product and safety design (cockpit display design; Dyson sound engineering; NHS medical device human factors — MHRA guidance; ANSI/AAMI HE75; automotive HMI — ISO 15008 visual demand); design accessibility solutions (RNIB tactile graphics; cochlear implant processor optimisation; RNID hearing loss; Universal Design — WCAG 2.1 colour contrast; simulating colour blindness); and contribute to pain science (FMRIB neuroimaging; NICE CG173 neuropathic pain; chronic pain — central sensitisation inventory).