perceptual development

sensation

the process of receiving and detecting stimuli from the environment through sensory organs (e.g., light detected by the eyes)

receptor

specialized cells that detect stimuli and convert them into neural signals (e.g., photoreceptors in the retina)

stimulus

any event or object that can evoke a sensory response. For example, light is a stimulus for vision

vision

the sense of sight, which is processed through the eyes and interpreted by the brain. Example: seeing colors, chapes, and movement

audition

the sense of hearing, processed by the ears. Example: listening to music

gustation

the sense of taste. Example: tasting sweetness in sugar

olfactory

the sense of smell. Example: smelling flowers

touch

the sense of feeling physical sensations through the skin. Example: feeling warmth or cold on your skin

haptic

pertaining to the sense of touch and perception of objects through physical interaction (e.g., tactile feedback from touching a textured surface)

kinesthetic

the sense of body position and movement. Example: knowing where your limbs are without looking at them

vestibular

the sense of balance and spatial orientation. Example: feeling dizzy when spinning in circles

intensity

refers to the strength or magnitude of a stimulus (e.g., the loudness of a sound)

wavelength

the distance between successive crests of a wave, determining the color in vision and pitch in hearing

purity

in sound, refers to the complexity of a sound wave; in vision, it refers to the richness of color

frequency

the rate at which a wave cycles, related to pitch in hearing (e.g., high-frequency sound = high pitch)

pitch

the percetion of the frequency of sound (high or low)

transduction

the process by which sensory receptors convert physical stimuli into neural signals that can be interpreted by the brain

adaptation

the process by which receptors become less responsive to a constant stimulus over time (e.g., becoming less aware of a smell after being exposed to it for a while)

perception

the process of organizing and interpreting sensory information to recognize meaningful objects and events

negative afterimage

a visual image that appears after staring at a bright image and then looking at a neural background, showing complementary colors

positive afterimage

a visual image that remains after the original images is no longer present, often seen in bright light

bottom-up processing

the process of building a perception from basic sensory information (e.g., noticing individual letters and forming a word)

top-down processing

the use of prior knowledge and expectations to interpret sensory information (e.g., recognizing a word from a umbled letter sequence)

absolute threshold

the minimum amount of stimulus energy required to detect a stimulus 50% of the time

difference threshold

the smallest difference between two stimuli that a person can detect

Weber’s Law

the principle that the just noticeable difference (JND) between two stimuli is a constant proportion of the original stimulus

signal detection theory

the theory that detecting a stimulus is influenced by both the intensity of the stimulus and the individual’s psychological state

sensory adaptation

the diminished sensitivity to a constant stimulus over time (e.g., no longer noticing the sound of traffic after living near it for a while)

habituation

a decrease in response to a repeated stimulus (e.g., becoming less startles by a noise over time)

occipital lobe

the region of the brain responsible for processing visual information

temporal lobe

the region of the brain associated with hearing, memory, and language processing

parietal lobe

the region of the brain involved in processing sensory information, including touch, temperature, and spatial awareness

frontal lobe

the region of the brain responsible for decision-making, planning, problem-solving, and voluntary motor movements

recognition

the ability to identify previously encountered stimuli

representation

the mental process of encoding and storing information about sensory experiences

psychophysics

the study of how physical stimuli are translated into psychological experiences

cerebral cortex

the outer layer of the brain involved higher-level function like sensation, perception, and cognition

parent report

a research method where parents provide information about their child’s behavior or development

self-report

a method where individuals provide information about their own behavior, feelings, or experiences

VOE (violation of expectation)

a research method often used in developmental psychology to assess infants’ expectation based on their surprise or lack of surprise at an event

conditioning

a process of learning associations between stimuli and responses (e.g., classical or operant conditioning)

blinking/pupillary light reflex

involuntary responses like blinking or pupil constriction in response to stimuli, used in developmental studies

preference

a method to assess infants’ preferences for one stimulus over another, often based on looking time or choice

affordance

the opportunities for action that objects or environments provide to an individual. Example: a door handle affords the action of opening the door

action observation (Adolph’s NYU Action Lab)

research shows the infants’ motor development is closely linked to their perception of the environment and ability to interact with it

exploratory behavior

actions aimed at learning about the environment, like touching or manipulating objects

unimodal

sensory information that comes from a single sensory modality, like visual input

multimodal

sensory information that is integrated across multiple modalities (e.g., hearing and seeing an object together)

photoreceptor

cells in the retina that respond to light, including rods (for low light) and cones (for color vision)

sclera

the white part of the eye, providing structure and protection

cornea

the transparent, curved outer layer of the eye that helps focus light

iris

the colored part of the eye, controlling the size of the pupil

pupil

the opening that allows light to enter the eye, changing size based on lighting conditions

lens

the structure behind pupil that focuses light onto the retina

retina

the light-sensitive layer at the back of the eye that converts light into neural signals

rod

photoreceptor cells that help with vision in low light

cone

photoreceptor cells that detect color and function in bright light

fovea

the central part of the retina responsible for sharp, detailed vision

blind spot

the area where the optic nerve cross, sending information to the opposite side of the brain

receptive field

the specific area of the visual field that a particular neuron responds to

optic chiasm

the point where the optic nerves cross, sending information to the opposite side of the brain

visual cortex

the area of the occipital lobe that processes visual information

accommodation

the eye’s ability to change the shape of the lens to focus on objects at different distances

acuity

the sharpness or clarity of vision, often measured with the Snellen chart

Snellen chart

a tool used to measure infants’ visual acuity by showing them high-contrast patterns

ERP (event-related potential)

a measure of brain activity in response to specific, used in studies of perception

influence of sensory elements

sensory modalities can influence each other, such as when vision affects hearing perception (e.g., McGurk effects - seeing lip movements influences what we hear)

perception steps

sensory deduction, transduction (conversion to neural signals), organization and interpretation, recognition and response

obstacles in perceptual development research

infants’ limited ability to communicate and ethical concerns with testing young children

affordance

an example could be a staircase as an affordance for climbing for an adult, but not for a toddler

action observation and Adolph’s lab

research shows that perception and motor development are closely intertwined. Infants’ exploration and action are influenced by their sensory input and ability to perceive affordances