Chapter 4 Flashcards
Sensation and Perception
Sensation
Simple stimulation of a sense organ. (Basic registration of light, sound, pressure, odor, or taste).
Perception
Organization, identification, and interpretation of a sensation in order to form a mental representation.
Transduction
The process whereby senses receptors convert physical signals from the environment into neural signals that are sent to the central nervous system.
Sensory Adaptation
The process whereby sensitivity to prolonged stimulation tends to decline over time as an organism adapts to current (unchanging conditions).
Psychophysics
Methods that systematically relate the physical characteristics of a stimulus to an observer’s perception.
Absolute Threshold
The minimal intensity needed to just barely detect a stimulus in 50% of the trials.
Sensitivity
How responsive we are to faint stimuli.
Acuity
How well we distinguish two very similar stimuli.
Just Noticeable Difference (JND)
The minimal change in a stimulus (e.g., in its loudness or brightness) that can just barely be detected.
Weber’s Law
For every sense domain, the change in a stimulus that is just noticeable is a constant proportion of the standard stimulus, over a broad range of intensities.
Signal Detection Theory (SDT)
A way of analyzing data from psychophysics experiments that measure an individual’s perceptual sensitivity while also taking notice, expectations, motivations, and goals into account.
Decision Criterion
The strength of the sensory evidence for the stimulus, and the amount of evidence necessary for your perceptual system to “decide” that the stimulus is present.
Cornea
Clear smooth outer tissue that bends light wave and sends it through the pupil.
Pupil
A hole in the colored part of the eye
Iris
Colored part of the eye, a translucent, doughnut-shaped muscle that control the size of the pupil and the amount of light that enters the eye.
Retina
A layer of light-sensitive tissue lining the back of the eyeball.
Accommodation
The process by which the eye maintains a clear image on the retina.
Cones
Photoreceptors that detect color, operate under normal daylight conditions, and allow us to focus on fine details.
Rods
Photoreceptors that become active only under low-light conditions, for night vision.
Fovea
An area of the retina where vision is clearest and there are no rods at all
Blind Spot
A location in the visual field that produces no sensation on the retina.
Area V1
The part of the occipital lobe that contains the primary visual cortex.
Binding Problem
How the brain links features together so that we see unified objects in our vision worlds rather than free-floating or miscombined features.
Illusory Conjunction
A perceptual mistake whereby the brain incorrectly combines features from multiple objects.
Attention
The active and conscious processing of particular information.
Perceptual Constancy
The principle that even as aspects of sensory signals change, perception remains constant.
Perceptual Contrast
The principle that although the sensory information from two things may be very similar, we perceive the objects as different.
Perceptual Organization
The process of grouping and segregating features to create whole objects organized in meaningful ways.
Monocular Depth Cues
Aspects of a scene that yield information about depth when viewed with only one eye.
Binocular Display
The difference in the retinal images of the two eyes.
Apparent Motion
Perception of movement as a result of alternating signals appearing a in rapid succession in different locations.
Change Blindness
Failure to detect changes to the visual details of a scene.
Inattentional Blindness
A failure to perceive objects that are not the focus of attention.
Pitch (Frequency)
How high or low a sound is, as ordered on a musical scale.
Loudness (Amplitude)
A sound’s intensity.
Timbre (Complexity)
The quality of sound that allows you to distinguish two sources with the same pitch and loudness.
Outer Ear
(Pinna, auditory canal: and ear drum) Collects sound waves and funnels then toward the middle ear.
Middle Ear
(Ossicles) Transmits the vibrations to the inner ear.
Inner Ear
Embedded in the skull, where they are transduced into neural impulses.
Cochlea “Snail”
A fluid-filled tube containing cells that transduce sound vibration to neural impulses.
Basilar Membrane
A structure in the inner ear that moves up and down in the time with vibration relayed from the ossicles, transmitted through the oval window.
Inner Hair Cells
Specialized auditory receptors neurons embedded in the basilar membrane.
Area A1
The primary auditory cortex, located in the temporal lobe.
Place Code
A process in which the brain uses information about hair cells across the whole basilar membrane to help determine the pitch you hear.
Temporal Code
A process in which the brain uses information about the timing of the action potentials in the auditory nerves to help determine the pitch you hear.
Haptic Perception
The active exploration of the environment by touching and grasping objects with our hands.
Referred Pain
Feeling of pain on the surface of the body, but due to internal damage, occurs when sensory information from internal and external areas converges on the same nerve cells in the spinal cord.
Gate-Control Theory
Holds that signals arriving from pain receptors in the body can be stopped, or gated, by interneurons in the spinal cord via feedback from the skin or brain.
Proprioception
Sense of body position.
Vestibular System
The three fluid-filled semicircular canals and adjacent organs located next to the cochlea in each inner ear.
Olfactory Receptor Neurons (ORNs)
Receptors cells that transduce odorant molecules into neural impulses.
Olfactory Bulb
A brain structure located above the nasal cavity beneath the frontal lobes.
Pheromones
Biochemical odorants emitted by other members of an animal’s spices that can affect the animal’s behavior or physiology.
Taste Buds
(In the papilla) The organs of taste transduction.
