Ch. 3 Sensation And Perception - Discovering Psyc (4Th Edition)

Front 1

What are sensation and perception?

Back 1

Sensation: refers to the detection and basic sensory experience of environmental stimuli, such as sounds, objects, and odors.

Hint 1

Perception: occurs when we integrate, organize and interpret sensory information in a way that is meaningful.

Front 2

Basic principles of sensation:

Back 2

-Key theme-
Sensation is the result of neural impulses transmitted to the brain from sensory receptors that have been stimulated by physical energy from the external environment.

Hint 2

Terms:

Sensory receptor: Specialized cells unique to each sense organ that respond to a particular form of sensory stimulation.

Front 3

What is the process of transduction?

Back 3

Transduction is the Process by which a form of physical energy is converted into a coded neural signal that can be processed by the nervous system.

Front 4

What is a sensory threshold, and what are the two main types of sensory thresholds?

Back 4

The point at which a stimulus is strong enough to be detected because it activates a sensory receptor cell.

Hint 4

Sensory Threshold types:

1. Absolute Threshold: the smallest possible strength of stimulus that can be detected half the time.

2. Difference Threshold: The smallest possible difference between two stimuli that can be detected half the time. (also called just noticeable difference)

Front 5

How does sensory adaption and Weber's law demonstrate that sensation is relative rather than absolute?

Back 5

-Sensory adaptation: The gradual decline in sensitivity to a constant stimulus.

-Weber's Law: "for each sense, the size of a just noticeable difference is a constant proportion of the size of the initial stimulus."

Hint 5

-So whether we can detect a change in strength of a stimulus depends on the intensity of the original stimulus.

-There is no one-to-one correspondence between the objective characteristics of a physical stimulus and our psychological experience of it.

Front 6

Strategies to control pain

Back 6

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Front 7

Hearing: From vibration to sound

Back 7

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Front 8

The Chemical and body sense: Smell, Touch, Taste, and position

Back 8

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Front 9

Perception

Back 9

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Front 10

Perceptual Illusions

Back 10

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Front 11

The effects of experience on Perceptual Interpretations

Back 11

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Front 12

Vision: From light to sight.

Back 12

-Key Theme-
The receptor cells for vision respond to the physical energy of light waves and are located in the retina of the eye.

Hint 12

Terms:

Retina: Thin membrane lining the back of eyeball; contains rods and cones

Front 13

What is the visible spectrum?

Back 13

the portion of the electromagnetic light spectrum that is visible to (can be detected by) the human eye.

Front 14

What are the key structures of the eye and their functions?

Back 14

-Eye structures-

-CORNEA: clear membrane that covers front of eye

-PUPIL: black opening in center of eye

-IRIS: colored structure of muscular tissue

-LENS: Transparent structure behind the pupil

-RETINA: Thin, light-sensitive membrane, lies at the back of the eye, covering most of it's inner surface. contains rods and cones (developed from brain tissue that migrated during fetal development)

-OPTIC DISK: Point where optic nerve leaves eye

-OPTIC NERVE (fibers): 1 mill Axons of Ganglion cells form fibers of optic nerve that exits behind eyes optic disk and connects to visual cortex of brain.

Hint 14

-Structure functions-

-CORNEA: helps gather and direct incoming light.

-PUPIL: opening that allows light in

-IRIS: contracts or expands to control size of pupil and amount of light entering the eye.

-LENS: In a process called ACCOMMODATION the lens thins or thickens to bend or focus the incoming light so it falls on the retina.

-RETINA: contains sensory receptor or photo receptor cells called Rods and Cones that respond to light by undergoing a chemical reaction that results in a neural signal.

-OPTIC DISK: No rods or cones in this part of retina, creating blind spot.

-OPTIC NERVE (fibers): carries visual information to visual cortex in the brain

Front 15

What are rods and cones, how do their functions differ?

Back 15

Photo receptor cells respond to light through chemical reaction for neural signal.

-ROD: long,thin, blunt ends (more in number - 125 mill.)

-CONE: short, thick, pointed ends (less in number - 7 mill.)

Hint 15

-Different Functions-

RODS: very sensitive to light, but not to color, responsible for peripheral vision and night vision.

CONES: Detect color, responsible for color vision and visual acuity in bright light. require more light than rods to function.

Front 16

What is a visual disorder and how are they caused?

Back 16

If the eyeball is abnormally shaped the lens may not properly focus the incoming light on the retina.

Hint 16

-Nearsightedness- Myopia:
distant objects appear blurry because the light reflected off objects focuses in the front of the retina.

-Farsightedness- Hyperopia:
Objects near the eyes appear blurry because light reflected off the objects is found behind the retina.

-middle age farsightedness- Presbyopia:
lens becomes brittle and inflexible

-Astigmatism: abnormally curved eyeball results in blurry vision for lines in a particular direction.

Front 17

Processing Visual Information

Back 17

-Key Theme-
Signals from the rods and cones undergo preliminary processing in the retina before they are transmitted to the brain.

Front 18

What are bipolar and ganglion cells, and how do their functions differ?

Back 18

BIPOLAR CELLS: specialized neurons in the retina that connect the rods and cones with the ganglion cells

GANGLION CELLS: specialized neurons in the Retina that reprocesses visual information. (this is possible because the retina develops from a bit of brain tissue that "migrates" during fetal development)

Front 19

How is visual information transmitted from the retina to the brain?

Back 19

1. Once visual information is preprocessed in the retina it travels through the optic nerve made of 1 mill axons of ganglion cells.

2. After exiting the eyes, the left and right optic nerves meet at the OPTIC CHIASM. The optic nerve splits in two. one set of axons cross to the other side of the brain. the other set forms a pathway that continues on the same side of the brain.

3. from optic chiasm, most optic nerve axons project to the thalamus brain structure (responsible for processing info about form, color, brightness, and depth)

4.Smaller number of nerve axons detour to areas in the midbrain before going to the thalamus (second pathway involved in processing location of an object)

5. From thalamus to visual cortex to decode and interpret information

6. Specialized Receiving Neurons in the visual cortex. Each responding to particular visual stimulation.

Hint 19

How visual information is transmitted

1. Optic Nerve

2 Optic Chiasm - Optic nerve splits, one set crosses, one continues.

3. Most optic nerve axons travel to the thalamus brain structure.

4. Smaller number of nerve axons detour to areas in the midbrain before going to the thalamus

5. From Thalamus to visual cortex

6. Specialized Receiving neurons inside visual cortex.

Front 20

What properties of light correspond to color perceptions?

Back 20

Color: Perceptual experience of different wave lengths of light, involving hue, saturation (Purity), and brightness (intensity)

Hue: The property of wavelengths of light known as color; Different wavelengths correspond to our subjective experience of different colors.

Saturation (Purity): The property of color that corresponds to the purity (singleness) of the light wave.

Brightness (intensity): The perceived intensity of a color, which corresponds to the amplitude of the light wave.

Front 21

how is color vision explained?

Back 21

Trichromatic theory of color vision: Theory that the sensation of color results because different varieties of cones in the retina are especially sensitive to red light (long wavelengths), green light (medium wavelengths), or blue light (short wavelengths). when a combination of color strikes the retina it stimulates a combination of cones.

Hint 21

Opponent-Process theory of color vision: Theory that color vision is the product of opposing pairs of color receptors, red-green, blue-yellow, and black-white. When one member of a color pair is stimulated, the other member is inhibited.