Sensory Processing and Perception in Psychology

Binocular Cues

Depth perception using both eyes' input.

Retinal Disparity

Difference in images between two eyes.

Convergence

Eyes contract for close objects, relax for distant.

Monocular Cues

Depth perception using one eye's input.

Relative Size

Larger objects appear closer than smaller ones.

Interposition

Overlapping objects indicate which is closer.

Relative Height

Higher objects perceived as farther away.

Shading and Contour

Light and shadow create depth perception.

Motion Parallax

Distant objects move slower than nearby ones.

Sensory Adaptation

Reduced sensitivity to constant stimuli over time.

Weber's Law

JND is proportional to stimulus intensity.

Just Noticeable Difference (JND)

Minimum change in stimulus detectable 50% of time.

Absolute Threshold

Minimum stimulus intensity detected 50% of the time.

Subliminal Stimuli

Stimuli below the absolute threshold of perception.

Vestibular System

Inner ear structures for balance and spatial orientation.

Semicircular Canals

Detect rotational movement of the head.

Otolithic Organs

Detect linear acceleration and head positioning.

Endolymph

Fluid in canals that aids in balance detection.

Signal Detection Theory

Decision-making under uncertainty regarding stimuli.

Strength of a Signal (d')

Variable indicating signal strength in detection.

Signal Detection Strategy (c)

Conservative or liberal approach to signal detection.

Bottom-Up Processing

Perception driven by sensory input.

Top-Down Processing

Perception influenced by prior knowledge.

Gestalt Principles

Psychological concepts for visual perception organization.

Similarity

Grouping items based on shared characteristics.

Pragnanz

Perception simplified to simplest forms.

Proximity

Objects close together perceived as a group.

Continuity

Lines perceived as following the smoothest path.

Closure

Perception of incomplete shapes as whole objects.

Conjunctiva

First layer light encounters in the eye.

Cornea

Transparent tissue covering anterior 1/6th of eyeball.

Pupil

Hole in iris controlling light entry.

Lens

Bends light to focus on retina.

Suspensory ligaments

Connect lens to ciliary muscle.

Ciliary body

Secretes aqueous humor and controls lens shape.

Retina

Layer containing photoreceptors for light detection.

Macula

Retina area rich in cones for sharp vision.

Fovea

Center of macula, entirely composed of cones.

Photoreceptors

Nerve cells converting light into neural impulses.

Rods

Photoreceptors for low-light vision, 120 million present.

Cones

Photoreceptors for color vision, 6-7 million present.

Phototransduction Cascade

Process converting light into neural signals.

Rhodopsin

Protein in rods that changes shape with light.

Transducin

Molecule that initiates phototransduction in rods.

Phosphodiesterase (PDE)

Enzyme converting cGMP to GMP in phototransduction.

Hyperpolarization

Process where rods turn off in response to light.

Cones

Specialized nerves for color vision in retina.

Rods

Photoreceptors for low-light and black-and-white vision.

Rhodopsin

Light-sensitive protein in rod cells.

Photopsin

Protein in cone cells for color detection.

Phototransduction cascade

Process triggered by light hitting photoreceptors.

Fovea

Central region of retina with high cone concentration.

Blind spot

Area in retina without photoreceptors.

Peripheral vision

Vision outside the direct line of sight.

Trichromatic theory

Theory explaining color vision via three cone types.

Parvocellular pathway

Visual pathway for color and form detection.

Magnocellular pathway

Visual pathway for motion detection and temporal resolution.

Parallel processing

Simultaneous processing of different visual stimuli.

Sound waves

Pressure variations in air creating auditory signals.

Frequency

Number of sound wave cycles per second.

Pinna

Outer part of the ear collecting sound.

Tympanic membrane

Eardrum that vibrates with sound waves.

Malleus

First bone in the middle ear.

Incus

Second bone in the middle ear.

Stapes

Third bone in the middle ear, connected to oval window.

Cochlea

Inner ear structure for sound processing.

Organ of Corti

Structure in cochlea containing hair cells.

Kinocilium

Filament in hair cells responding to fluid movement.

Auditory nerve

Nerve transmitting sound information to the brain.

Kinocilium

Hair-like structure in auditory sensory cells.

Tip Link

Connects kinocilia and opens K channels.

K Channel

Potassium channel activated by tip links.

Action Potential (AP)

Electrical signal triggered in spiral ganglion cells.

Auditory Nerve

Transmits auditory information to the brain.

Cochlea

Inner ear structure for sound differentiation.

Basilar Tuning

Hair cells respond to specific sound frequencies.

Tonotypical Mapping

Brain's organization of sound frequency processing.

Apex of Cochlea

Activated by low frequency sounds (25 Hz).

Base of Cochlea

Activated by high frequency sounds (1600 Hz).

Somatosensation

Sense of body sensations like temperature and pain.

Thermoception

Sense of temperature through specialized receptors.

Mechanoception

Sense of pressure through mechanoreceptors.

Nociception

Sense of pain through nociceptors.

Proprioception

Awareness of body position and movement.

Kinaesthesia

Sense of body movement, excluding balance.

Sensory Adaptation

Decreased response to constant stimulus over time.

Amplification

Increased sensitivity to stimuli through receptor activation.

Somatosensory Homunculus

Topographical map of body sensations in cortex.

TrypV1 Receptor

Receptor for pain and temperature sensing.

A-beta Fibres

Fast, myelinated fibres for touch sensation.

A-delta Fibres

Medium fibres for sharp pain sensation.

C Fibres

Slow, unmyelinated fibres for lingering pain.

Olfaction

Sense of smell, crucial for taste perception.

Olfactory epithelium

Nasal area containing receptors for smell.

Cribriform plate

Bone separating olfactory epithelium from brain.

Olfactory bulb

Brain structure processing smell signals.

Receptors

Proteins sensitive to specific molecules in smell.

Glomerulus

Cluster of olfactory nerve endings in bulb.

Mitral cell

Neuron transmitting olfactory signals to brain.

GPCR

G-protein coupled receptor involved in smell.