PSYC 101 - MIDTERM 2

Sensation

Simple stimulation of a sense organ; basic registration of light, sound, pressure, odour, or taste.

Perception

The organization, identification, and interpretation of a sensation in order to form a mental representation.

Transduction

The process by which sense receptors convert physical signals from the environment into neural signals.

Sensory Adaptation

The decline in sensitivity to prolonged stimulation as an organism adapts to unchanging conditions.

Absolute Threshold

The minimal intensity needed to just barely detect a stimulus in 50% of trials.

Sensitivity

How responsive we are to faint stimuli.

Acuity

How well we can distinguish two very similar stimuli.

Just Noticeable Difference (JND)

The minimal change in a stimulus that can just barely be detected.

Weber’s Law

States that the change in a stimulus that is just noticeable is a constant proportion despite variations in intensity.

Signal Detection Theory

The response to a stimulus depends on a person’s sensitivity to the stimulus and their decision criterion.

Cornea

The transparent front part of the eye that bends light waves and sends them through the pupil.

Pupil

A hole in the coloured part of the eye that regulates light entry.

Retina

A layer of light-sensitive tissue lining the back of the eyeball.

Accomodation

The process by which the eye maintains a clear image on the retina.

Myopia

Nearsightedness; occurs when the eyeball is too long, causing images to focus in front of the retina.

Hyperopia

Farsightedness; occurs when the eyeball is too short, causing images to focus behind the retina.

Cones

Photoreceptors that detect colour and function well in bright light conditions.

Rods

Photoreceptors that become active under low-light conditions for night vision.

Fovea

The area of the retina where vision is clearest and contains no rods.

Blind Spot

A location in the visual field that produces no sensation on the retina.

Visual Receptive Field

The region of the visual field to which each neuron responds.

Ventral Stream

A pathway that processes object shape and identity.

Dorsal Stream

A pathway that identifies where an object is and how it is moving.

Visual Form Agnosia

The inability to recognize objects by sight.

Binding Problem

How the brain links features together to produce a unified perceptual experience.

Parallel Processing

The brain’s ability to perform multiple tasks simultaneously.

Illusory Conjunction

A perceptual mistake where the brain incorrectly combines features from different objects.

Attention

The active and conscious processing of particular information.

Perceptual Constancy

Perception remains constant even as sensory signals change.

Monocular Depth Cues

Visual cues for depth used with one eye.

Binocular Disparity

Difference in the retinal images of the two eyes providing depth information.

Apparent Motion

Perception of movement caused by alternating signals appearing in rapid succession.

Biological Motion Perception

The ability to recognize motion in biological entities.

Spatial Acuity

The ability to distinguish two stimuli that are very close together in space.

Temporal Acuity

The ability to distinguish two stimuli that are very close together in time.

Multisensory

Simultaneous stimulation of multiple senses.

Ventriloquist Illusion

Reliance on visual information for spatial location.

Change Blindness

Failure to detect changes in visual details of a scene.

Inattentional Blindness

Failure to perceive objects when not the focus of attention.

Sound Waves

Changes in air pressure that occur over time.

Pitch

The perceived frequency of sound, determining how high or low it sounds.

Loudness

The perception of a sound’s intensity.

Timbre

The quality of sound that differentiates between sources with the same pitch and loudness.

Cochlea

Fluid-filled tube in the inner ear that transduces sound vibrations.

Basilar Membrane

Structure in the inner ear that moves in response to sound vibrations.

Inner Hair Cells

Auditory receptor neurons embedded in the basilar membrane.

Area A1

The primary auditory cortex located in the temporal lobe.

Place Code

Determination of pitch based on the relative activity of hairs cells across the basilar membrane.

Temporal Code

Determination of pitch based on the timing of action potentials in the auditory nerve.

Haptic Perception

Active exploration of the environment through touch.

Tactile Receptive Field

Patch of skin that provides information about touch sensations.

Referred Pain

Pain perception occurring when different areas of the body share nerve pathways.

Gate-Control Theory

The theory that pain signals can be hindered by other sensory messages.

Proprioception

The sense of body position.

Vestibular System

The system that contributes to balance, consisting of semicircular canals.

Olfactory Receptor Neurons (ORNs)

Cells that transduce odourant molecules into neural signals.

Olfactory Bulb

The brain structure that processes smells, located above the nasal cavity.

Pheromones

Chemical signals emitted by animals that influence behaviour.

Taste Buds

Sensory organs for taste transduction.

Learning

The acquisition of new knowledge, skills, or responses due to experience.

Habituation

A process where repeated exposure to a stimulus reduces reaction.

Sensitization

Increased response to a later stimulus following initial stimulus exposure.

Classical Conditioning

Learning through association between neutral stimulus and unconditioned stimulus.

Unconditioned Stimulus (US)

A stimulus that naturally triggers a response.

Unconditioned Response (UR)

A natural reaction to an unconditioned stimulus.

Acquisition

The phase where the conditioned stimulus and unconditioned stimulus are paired.

Conditioned Stimulus (CS)

A previously neutral stimulus that begins to elicit a response after association with an unconditioned stimulus.

Conditioned Response (CR)

The learned response to a conditioned stimulus.

Second-Order Conditioning

Learning in which a CS is paired with a stimulus previously associated with a US.

Extinction

The process of reducing a conditioned response by not presenting the US.

Spontaneous Recovery

The reappearance of a conditioned response after a rest period.

Generalization

Responding similarly to similar stimuli.

Discrimination

The ability to differentiate between similar stimuli.

Biological Preparedness

The tendency to learn certain associations easily.

Operant Conditioning

Learning where behavior is influenced by its consequences.

Operant Behaviour

Behaviour that influences the environment.

Reinforcer

Any stimulus that increases the likelihood of a behavior occurring again.

Punisher

Any stimulus that reduces the likelihood of a behavior occurring again.

Primary Reinforcers

Reinforcers that satisfy biological needs (e.g., food).

Secondary Reinforcers

Reinforcers that derive effectiveness from association with primary reinforcers.

Fixed-Interval (FI) Schedule

Reinforcement after a fixed amount of time.

Variable-Interval (VI) Schedule

Reinforcement after varying amounts of time on average.

Fixed-Ratio (FR) Schedule

Reinforcement after a specific number of responses.

Variable-Ratio Schedule

Reinforcement after a variable number of responses on average.

Intermittent Reinforcement

Only some behaviors receive reinforcement.

Intermittent Reinforcement Effect

Behaviors maintained through intermittent reinforcement resist extinction better.

Shaping

Learning achieved by reinforcing successive approximations toward a desired behavior.

Latent Learning

Learning not immediately reflected in behavior.

Cognitive Map

A mental representation of the environment.

Observational Learning

Learning that occurs by observing others.

Diffusion Chain

Process of learning a behavior by observing someone and then teaching others.

Implicit Learning

Learning occurring without conscious awareness.

Memory

The ability to store and retrieve information over time.

Encoding

The process of transforming perceptions into enduring memories.

Storage

Maintaining information in memory over time.

Retrieval

Bringing to mind previously encoded and stored information.

Semantic Encoding

Relating new information to existing knowledge.

Visual Imagery Encoding

Converting information into mental images for storage.

Organizational Encoding

Categorizing information based on relationships among items.

Mnemonics

Techniques that improve memory retrieval.