Sensation And Perception - Vocab.

Front 1

A reduction in response caused by prior or continuing stimulation.

Back 1

Adaptation

Front 2

A receptor that converts physical energy from the environment into neural activity.

Back 2

Sensory Transductor

Front 3

The idea that the mind produces ideas that are not derived from external sources, and that we have abilities that are innate and not learned.

Back 3

Nativism

Front 4

The idea that both mind and body exist.

Back 4

Dualism

Front 5

The idea that mind and matter are formed from, or reducible to, a single ultimate substance or principle of being.

Back 5

Monism

Front 6

The idea that physical matter is the only reality, and everything including the mind can be explained in terms of matter and physical phenomena; a type of monism.

Back 6

Materialism

Front 7

The idea that the mind is the true reality and objects exist only as aspects of the mind's awareness; a type of monism.

Back 7

Mentalism

Front 8

Originated by Rene Descartes, the idea positing the existence of two distinct principles of being in the universe: spirit/soul and matter/body.

Back 8

Mind-Body Dualism

Front 9

The idea that experience from the senses is the only source of knowledge.

Back 9

Empiricism

Front 10

The idea that all matter has consciousness.

Back 10

Panpsychism

Front 11

The science of defining quantitative relationships between physical and psychological (subjective) events.

Back 11

Psychophysics

Front 12

The minimum distance at which two stimuli (e.g. two simultaneous touches) are just perceptible as separate.

Back 12

Two-Point Touch Threshold

Front 13

The smallest detectable difference between two stimuli, or the minimum change in a stimulus that enables it to be correctly judged as different from a reference stimulus.

Back 13

Just Noticeable Difference (JND)/ Difference Threshold

Front 14

The constant of proportionality in Weber's Law.

Back 14

Weber Fraction

Front 15

The principle that the just noticeable difference (JND) is a constant fraction of the comparison stimulus.

Back 15

Weber's Law

Front 16

A principle describing the relationship between stimulus and resulting sensation such that the magnitude of subjective sensation increases proportionally to the logarithm of the stimulus intensity.

Back 16

Fechner's Law

Front 17

The minimum amount of stimulus necessary for a person to detect a stimulus 50% of the time.

Back 17

Absolute Threshold

Front 18

A psycho-physical method in which many stimuli, ranging from rarely to almost always perceivable(or rarely to almost always perceivably different from a reference stimulus), are presented one at a time. Participants respond to each presentation: "yes"/"no," "same"/"different," and so on.

Back 18

Method of Constant Stimuli

Front 19

A psycho-physical method in which the particular dimension of a stimulus, or the difference between two stimuli, is varied incrementally until the participant responds differently.

Back 19

Method of Limits

Front 20

The method of limits for which the subject controls the change in the stimulus.

Back 20

Method of Adjustment

Front 21

In studies of signal detection, the graphical plot of the hit rate as function of the false alarm rate. If these are the same, points fall on the diagonal, indicating that the observer cannot tell the difference between the presence and absence of the signal. As the observer's sensitivity increases, the curve bows upward toward the upper left corner. That point represents a perfect ability to distinguish signal from noise (100% hits, 0% false alarms).

Back 21

Receiver Operating Characteristics (ROC) Curve

Front 22

A psycho-physical theory that quantifies the response of an observer to the presentation of a signal in the presence of noise. Measures attained from a series of presentations are sensitivity (d') and criterion of the observer.

Back 22

Signal Detection Theory

Front 23

A psycho-physical method in which the participant assigns values according to perceived magnitudes of the stimuli.

Back 23

Magnitude Estimation

Front 24

The ability to match the intensities of situations that come from different sensory modalities. This ability enables insight into sensory differences. For example, a listener might adjust the brightness of the light until it matches the loudness of a tone.

Back 24

Cross-Modality Matching

Front 25

A principle describing the relationship between stimulus and resulting sensation, such that the magnitude of subjective sensation is proportional to the stimulus magnitude raised to an exponent.

Back 25

Stevens' Power Law

Front 26

A doctrine formulated by Johannes Muller stating that the nature of a sensation depends on which sensory fibers are stimulated, not on how fibers are stimulated.

Back 26

Doctrine of Specific Nerve Energies

Front 27

Twelve pairs of nerves (one for each side of the body) that originate in the brain stem and reach sense organs and muscles through openings on the skull.

Back 27

Cranial Nerves

Front 28

The first pair of cranial nerves, which conduct impulses from the mucous membrane of the nose to the olfactory bulb.

Back 28

Olfactory (I) Nerves

Front 29

The second pair of cranial nerves, which arise from the retina and carry visual information to the thalamus and other parts of the brain.

Back 29

Optic (II) Nerves

Front 30

The eighth pair of cranial nerves, which connect the inner ear with the brain, transmitting impulses concerned with hearing and balance; composed of the cochlear nerve and the vestibular nerve.

Back 30

Auditory (VIII) Nerves/ Vestibulo-Cochlear Nerve)

Front 31

The third pair of cranial nerves, which innervate all the extrinsic muscles of the eye except the lateral rectus and the superior oblique muscles, and which innervate the elevator muscle of the upper eyelid, the ciliary muscle, and the sphincter muscle of the pupil.

Back 31

Oculomotor (III) Nerves

Front 32

The fourth pair of cranial nerves, which innervate the superior oblique muscles of the eyeballs.

Back 32

Trochlear (IV) Nerves

Front 33

The sixth pair of cranial nerves, which innervate the lateral rectus muscle of each eye.

Back 33

Abducens (VI) Nerves

Front 34

Blending multiple sensory systems.

Back 34

Polysensory

Front 35

The idea that "vital forces" are active within living organisms, and these forces cannot be explained by physical processes of matter more generally.

Back 35

Vitalism

Front 36

The junction between neurons that permits information transfer.

Back 36

Synapse

Front 37

A chemical substance used in transmission; usually back toward ion at synapses.

Back 37

Neurotransmitter

Front 38

An oscillation that travels through a medium by transferring energy from one particle or point to another without causing and permanent displacement of the medium.

Back 38

Wave

Front 39

A quantum of visible light or other form of electromagnetic radiation demonstrating both particle and wave properties.

Back 39

Photon

Front 40

To take up light, noise, or energy and not transmit it at all.

Back 40

Absorb

Front 41

To disperse light in an irregular fashion.

Back 41

Scatter

Front 42

To redirect something that strikes a surface - especially light, sound, or heat - usually back toward its point of origin.

Back 42

Reflect

Front 43

To convey something (e.g. light) from one place or thing to another.

Back 43

Transmit

Front 44

1. To alter the course of a wave of energy that passes into something from another medium, as water does to light entering it from the air. 2. To measure the degree of refraction in a lens or eye.

Back 44

Refract

Front 45

A picture or likeness.

Back 45

Image

Front 46

The transparent "window" into the eyeball.

Back 46

Cornea

Front 47

Allowing light to pass through with no interruption so that objects on the other side can be clearly seen.

Back 47

Transparent

Front 48

The watery fluid in the anterior chamber of the eye.

Back 48

Aqueous Humor

Front 49

The lens in side the eye that enables changing focus.

Back 49

Crystalline Lens

Front 50

The dark circular opening at the center of the iris in the eye, where light enters the eye.

Back 50

Pupil

Front 51

The colored part of the eye, consisting of a muscular diaphragm surrounding the pupil and regulating the light entering the eye by expanding and contracting the pupil.

Back 51

Iris

Front 52

The transparent fluid that fills the vitreous chamber in the posterior part of the eye.

Back 52

Vitreous Humor

Front 53

A light-sensitive membrane in the back of the eye that contains rods and cones, which receive an image from the lens and send it to the brain through the optic nerve.

Back 53

Retina

Front 54

The process by which the eye changes its focus (in which the lens gets fatter as gaze is directed toward nearer objects).

Back 54

Accommodation

Front 55

Literally "old sight." The loss of near vision because of insufficient accommodation.

Back 55

Presbyopia

Front 56

Opacity of the crystalline lens.

Back 56

Cataract

Front 57

The condition in which there is no refractive error, because the refractive power of the eye is perfectly matched to the length of the eyeball.

Back 57

Emmetropia

Front 58

A common condition in which light entering the eye is focused behind the retina.

Back 58

Hyperopia

Front 59

A visual defect caused by the unequal curving of one or more of the refractive surfaces of the eye, usually the cornea.

Back 59

Astigmatism

Front 60

Referring to the convertion from one form of energy (e.g. light) to another (e.g. electricity).

Back 60

Transduced

Front 61

The back layer of the retina - what the eye doctor sees through an ophthalmoscope.

Back 61

Fundus

Front 62

Photoreceptors specialized for night vision.

Back 62

Rods

Front 63

Photoreceptors specialized for day-light vision, fine visual acuity, and color.

Back 63

Cones

Front 64

In reference to the retina, consisting of two parts: the rods and cones, which operate under different conditions.

Back 64

Duplex

Front 65

The part of a photoreceptor that contains photopigment molecules.

Back 65

Outer Segment

Front 66

The part of a photoreceptor that lies between the outer segment and the cell nucleus.

Back 66

Inner Segment

Front 67

The location where axons terminate at the synapse for transmission of information by release of a chemical transmitter.

Back 67

Synaptic Terminal

Front 68

The light-catching part of the visual pigments of the retina.

Back 68

Chromophore

Front 69

The visual pigment found in rods.

Back 69

Rhodopsin

Front 70

Activation by light.

Back 70

Photoactivation

Front 71

The increase in membrane potential where the inner membrane surface becomes more negative than the outer membrane surface.

Back 71

Hyperpolarization

Front 72

The electrical potential that can vary continuously in amplitude.

Back 72

Graded Potential

Front 73

The distance between the retinal image and the fovea.

Back 73

Eccentricity

Front 74

Specialized retinal cells that contact both photoreceptor and bipolar cells.

Back 74

Horizontal Cells

Front 75

Antagonistic neural interaction between adjacent regions of the retina.

Back 75

Lateral Inhibition

Front 76

Retinal cells found in the inner synaptic layer that make synaptic contacts with bipolar cells, ganglion cells, and one another.

Back 76

Amacrine Cells

Front 77

Retinal cells that synapse with either rods or cones (not both) and with horizontal cells, and then pass the signals on to ganglion cells.

Back 77

Bipolar Cells

Front 78

Bipolar retinal cells whose processes are spread out to receive input from multiple cones.

Back 78

Diffuse Bipolar Cells

Front 79

1. The ability to perceive via the sense organs. 2. Extreme responsiveness to radiation, especially to light of a specific wavelength. 3. The ability to respond to transmitted signals.

Back 79

Sensitivity

Front 80

A measure of the finest detail that can be resolved by the eyes.

Back 80

Visual Acuity

Front 81

Small cone bipolar cells in the central retina that receive input from a single cone.

Back 81

Midget Bipolar Cells

Front 82

Bipolar cells that respond to an increase in light captured by the cones.

Back 82

ON Bipolar Cells

Front 83

Bipolar cells that respond to a decrease in light captured by the cones.

Back 83

OFF Bipolar Cells

Front 84

Retinal cells that receive visual information from photoreceptors via two intermediate neuron types (bipolar cells and amacrine cells) and transmit information to the brain and the midbrain,

Back 84

Ganglion Cells

Front 85

Small ganglion cells that receive excitatory input from single midget bipolar cells in the central retina and feed the parvocellular layer of the lateral geniculate nucleus.

Back 85

P Ganglion Cells

Front 86

Ganglion cells resembling little umbrellas that receive excitatory input from diffuse bipolar cells and feed the magnocellular layer of the lateral geniculate nucleus.

Back 86

M Ganglion Cells

Front 87

The region on the retina in which visual stimuli influence a neuron's firing rate.

Back 87

Receptive Field

Front 88

A cell that depolarizes in response to an increase in light intensity in its receptive field center.

Back 88

ON-center Cell

Front 89

A cell that depolarizes in response to a decrease in light intensity in its receptive field center.

Back 89

OFF-center Cell

Front 90

An acoustic, electrical, electronic , or optical device, instrument, computer program, or neuron that allows the passage of some frequencies or digital elements and blocks the passage of others.

Back 90

Filter

Front 91

The difference in luminance between an object and the background, or between lighter and darker parts of the same object.

Back 91

Contrast

Front 92

A progressive degeneration of the retina that affects night vision and peripheral vision. RP commonly runs in families and can be caused by defects in a number of different genes that have recently been identified.

Back 92

Retinitis Pigmentosa (RP)

Front 93

For a grating, a pair consisting of one dark bar and one bright bar.

Back 93

Cycle

Front 94

The angle subtended by an object at the retina.

Back 94

Visual Angle

Front 95

A grating with a sinusoidal luminance profile.

Back 95

Sine Wave Grating

Front 96

Misperception of a grating due to undersampling.

Back 96

Aliasing

Front 97

The number of cycles of a grating per unit of visual angle (usually specified in degrees).

Back 97

Spatial Frequency

Front 98

The number of dark and bright bars per degree of visual angle.

Back 98

Cycles per Degree

Front 99

A function describing how the sensitivity to contrast (defined as the reciprocal of the contrast threshold) depends on the spatial frequency (size) of the stimulus.

Back 99

Contrast Sensitivity Function (CSF)

Front 100

The relative position of a grating.

Back 100

Phase

Front 101

A structure in the thalamus, part of the midbrain, that receives input from the retinal ganglion cells and has input and output connections to the visual cortex.

Back 101

Lateral Geniculate Nucleus (LGN)

Front 102

The neurons in the bottom two layers of the lateral geniculate nucleus, which are physically larger than the top two layers.

Back 102

Magnocellular layers

Front 103

The neurons in the top four layers of the LGN, which are physically smaller than those in the bottom four layers.

Back 103

Parvocellular Layers

Front 104

Referring to the opposite side of the body (or brain).

Back 104

Contralateral

Front 105

Referring to the same side of the body (or brain).

Back 105

Ipsilateral

Front 106

The orderly mapping of the world in the lateral geniculate nucleus and the visual cortex.

Back 106

Topographical Mapping

Front 107

The area of the cerebral cortex of the brain that receives direct input from the lateral geniculate nucleus, as well as feedback from other brain areas and is responsible for processing visual information.

Back 107

Primary Visual Cortex/ Area 17/ Striate Cortex

Front 108

The amount of cortical area (usually specified in millimeters) devoted to a specific region (e.g. 1 degree) in the visual field.

Back 108

Cortical Magnification

Front 109

The tendency of neurons in striate cortex to respond optimally to certain orientation and less to others.

Back 109

Orientation Tuning

Front 110

The property of the receptive fields of striate cortex neurons by which they demonstrate a preference, responding somewhat more rapidly when a stimulus is presented in one eye than when it is presented in the other.

Back 110

Ocular Dominance

Front 111

A cortical neuron with clearly defined excitatory and inhibitory regions.

Back 111

Simple Cell

Front 112

A neuron whose receptive-field characteristics cannot be easily predicted by mapping with spots of light.

Back 112

Complex Cell

Front 113

The process by which a cell in the cortex first increases its firing rate as the bar length increases to fill up its receptive field, and then decreases its firing rate as the bar is lengthened further.

Back 113

End Stopping

Front 114

A vertical arrangement of neurons.

Back 114

Column

Front 115

A 1-millimeter block of striate cortex containing two sets of columns, each covering every possible orientation (0-180 degrees), with one set preferring input from the left eye and one set preferring input from the right eye.

Back 115

Hypercolumn

Front 116

An enzyme used to reveal the regular array of "CO blobs," which are spaced about 0.5 millimeters apart in the primary visual cortex.

Back 116

Cytochrome Oxidase (CO)

Front 117

A perceptual illusion of tilt, produced by adaptation to a pattern of a given orientation.

Back 117

Tilt Aftereffect

Front 118

A pattern analyzer, implemented by an ensemble of cortical neurons, in which each set of neurons is tuned to a limited range of spatial frequencies.

Back 118

Spatial-Frequency Channel

Front 119

A misalignment of the two eyes such as a single object in space is imagined on the fovea of one eye, and on a nonfoveal area of the other (turned) eye.

Back 119

Strabismus

Front 120

A developmental disorder that is characterized by reduced spatial vision in an otherwise healthy eye, even with proper correction for refractive error.

Back 120

Amblyopia/ "Lazy Eye"