psyc midterm chapter 4

Question 1

What is sensation?

Answer 1

Detection of physical energy by our sense organs (light, smell, sound).

Question 2

What is perception?

Answer 2

The brain’s interpretation of these raw sensory inputs.

Question 3

What is transduction?

Answer 3

The nervous system converts an external stimulus into electrical signals within neurons. (for example auditory system; hair cells in the ear are where transduction occurs and where auditory information takes place).

Question 4

When is sense activation the greatest?

Answer 4

The smallest change in the intensity of a stimulus that we can detect. (sensory receptors)

Question 5

What is sensory adaptation?

Answer 5

Process in which activation is the greatest when stimulus is first detected. (sitting down, we feel it for the first couple seconds then we don’t constantly focus on it after)

Question 6

What is psychophysics?

Answer 6

Study of how we perceive sensory stimuli based on physical characteristics (Gustav Fechner - 1860)

Question 7

What is the absolute threshold of a stimulus?

Answer 7

The lowest level of stimulus needed for the nervous system to detect 50% of the time.

Question 8

What is the just noticeable difference (JND) or difference threshold?

Answer 8

Is the smallest change in the intensity of a stimulus that we can detect. The JND is relevant tour ability to distinguish a stronger stimulus from a weaker stimulus (soft noise against a slightly louder noise) (Just Noticeable Difference).

Question 9

What is Weber’s Law?

Answer 9

There is a constant proportional relationship between the JND and the original stimulus intensity, a proportionate increase.

Question 10

What is Weber’s fraction?

Answer 10

Weber’s fraction is the constant ratio of the just noticeable difference (JND) to the initial stimulus intensity. It describes how much a stimulus must change for a person to detect the difference. The fraction remains constant for a given type of stimulus, meaning that larger stimuli require a larger absolute change to notice a difference, but the proportion (or fraction) stays the same.

Question 11

What is the signal detection theory, and can you give an example of it?

Answer 11

Theory of how stimulus is detected under different conditions. (trying to hear someone’s call with poor cellular connection).

Question 12

Do you know what response biases are?

Answer 12

Our tendencies to make one type of guess over another when we were in doubt about whether a weak signal is present or absent under noisy conditions. They developed a clever way to take into account some people’s tendency to say “yes” when they are uncertain and other people’s tendency to say “no” when they are uncertain.

Question 13

Can you explain the difference between true positive (hit), false negative (miss),
false positive (false alarm), and true negative (correct rejection)? (there is a picture you should study!)

Answer 13

Hit: detect stimulus that was present.
Miss: fail to detect a stimulus that was present.
False alarm: indicate a stimulus was present, when it was not.
Correct rejection: indicate there was no stimulus, when there was no stimulus.

Question 14

Are sensory systems independent?

Answer 14

No, sensory systems are not completely independent. While each sensory system (e.g., vision, hearing, touch) processes specific types of information, they often interact and influence each other. This is known as sensory integration. For example, vision can affect how we perceive sound (the McGurk effect), and touch can influence our sense of balance. Sensory systems work together to provide a more comprehensive perception of the environment.

Question 15

Can you explain the McGurk effect?

Answer 15

Demonstrates that we integrate visual and auditory information when processing spoken language, and our brains automatically calculate the most probable sound given then information from the two sources. In the McGurk effect, hearing the syllable “ba” spoken readily while seeing a video track of a different syllable “ga” produces the perceptual experience of a different third sound “da”. This third sound is the brain’s best “guess” at integrating the two conflicting sources of information.

Question 16

What is synesthesia? Can you give some examples of synesthesia?

Answer 16

Synesthesia is when people experience cross module sensations. Chromesthesia; sounds trigger the experience of colour, can trigger strong emotions such as anger or fear. Mirror-touch; a person experiences the same sensation that another person experiences, such as touch. Number-form; numbers are imagined as mental maps.

Question 17

Describe the role of attention.

Answer 17

Our brains are immersed in a sea of sensory input, flexible attention is critical to our survival and well-being. Any moment we must be prepared to use our sensory information that signals a potential threat. (two roles of attention selective and inattentional)

Question 18

What is Selective Attention?

Answer 18

Process of selecting one sensory channel and ignoring or minimizing others. The major brain regions that control selective attention are the reticular activating system and the forebrain.

Question 19

Can you explain the cocktail party effect?

Answer 19

An attention related phenomenon refers to our ability to pick out important information from a conversation we aren’t engaged in or a part of.

Question 20

What is Inattentional Blindness?

Answer 20

Failure to detect stimuli that we are in plain sight when our attention is focused elsewhere.

Question 21

What is the binding problem?

Answer 21

Our brains manage to combine or “bind” these diverse pieces of information into a unified whole. Binding may explain many aspects of perception and attention. When we see the world, we rely on shape, motion, colour, and depth cues, each of which requires different amounts of time to detect individually. Yet our minds seamlessly combine these visual cues into a unified perception of a scene.

Question 22

Light waves vary in amplitude, wavelength, and purity. How do amplitude, wavelength, and purity affect or impact the perception of light?

Answer 22

Visible light has a wavelength in hundreds of nanometres. We only respond to a narrow range of wavelengths of lights. Our perceptions of an object’s brightness is influenced directly by the intensity of the reflected light that reaches our eye.Amplitude: Affects brightness—greater amplitude results in brighter light, while smaller amplitude leads to dimmer light.
Wavelength: Affects color (hue)—different wavelengths correspond to different colors on the visible spectrum. For example, shorter wavelengths (around 400 nm) appear violet, and longer wavelengths (around 700 nm) appear red.
Purity: Affects saturation (color intensity)—higher purity (less mixture of wavelengths) results in more vivid, pure colors, while lower purity (more mixed wavelengths) produces duller, less saturated colors.

Question 23

Do wavelengths have colour? Why or why not. Explain.

Answer 23

Mixing primary colors together to make pigment creates a certain wavelength, which leaves little or no color. Wavelengths themselves don’t have color; rather, they correspond to colors in the visible spectrum. When light of different wavelengths enters the eye, it is processed by the brain and interpreted as color. For example, a wavelength of about 480 nm is perceived as blue, and around 650 nm, it is seen as red. The perception of color is a result of how light interacts with the photoreceptors in our eyes, not an inherent property of the wavelengths themselves.

Question 24

How does the eye see?

Answer 24

Reflected light enters the pupil, cornea and lens focuses light on the retina to form images. Once light hits the retina, receptors are activated lens which are capable of accommodation. Light rays will then reach the back of the eyes and form an image.

Question 25

What are the main components of the eye? (look at diagram)

Answer 25

Optic nerve; transmits impulses from the retina to the rest of the brain. Retina; innermost layer of the eye, where incoming light is converted into nerve impulses. Eye muscle; one of the six surrounding muscles that rotate the eye in all directions. Sclera- the white of the eye. Pupil; opening in the center of the iris that lets in light. In charge of dilation and expansion. Iris; coloured area containing muscles that control the pupil. Cornea; curved, transparent dome that bends incoming light to focus the incoming visual to the back of the eye. Covers the iris and pupil. Lens; transparent disk that focuses light rays for the near or distant vision.

Question 26

What role does the cornea play in vision?

Answer 26

Its shape bends the incoming light to focus the incoming visual image at the back of the eye.

Question 27

What role does the lens play in vision?

Answer 27

Bends light, changes curvature, allowing fine tune the visual image called accommodation. The lens changes shape to focus light on the back of the eye; this way the eye can perceive distances of objects.

Question 28

What kinds of accommodations (or adjustments) can the lens make?

Answer 28

“Fat” which makes the lens short and wide allowing near vision. “Flat” makes the lens long and skinny allowing us to see distant objects.

Question 29

How is light focused in the eye?

Answer 29

Light is focused in the eye through the cornea, lens, and pupil: Cornea: When light enters the eye, the cornea (the transparent outer layer) bends (refracts) the light to begin focusing it. Pupil: The pupil controls how much light enters the eye by adjusting its size, depending on the lighting conditions. Lens: The light passes through the pupil and is further focused by the lens, which changes shape (via the ciliary muscles) to fine-tune focus for objects at different distances. Retina: The focused light is then directed onto the retina, where photoreceptor cells (rods and cones) convert the light into electrical signals that are sent to the brain, creating a visual image. This process ensures that light is focused accurately onto the retina for clear vision.

Question 30

What is Presbyopia? And how does it interact with age?

Answer 30

As our vision tends to worsen as we become older our lens loses its flexibility overtime, this is called prebyopia.

Question 31

What is the “near point?” How does near point relate to presbyopia?

Answer 31

The near point is the closest distance at which the eye can focus on an object clearly. For a young, healthy eye, this is typically about 10–15 cm from the eye. Presbyopia is the age-related condition in which the lens of the eye loses its flexibility, making it harder to focus on close objects. As a result, the near point moves farther away because the eye's ability to change the shape of the lens (to focus on nearby objects) declines. This is why people with presbyopia often need reading glasses or other corrective lenses to see objects up close.

Question 32

Do you know the difference between Myopia and Hyperopia, and can you explain each condition?

Answer 32

Myopia; nearsightedness results when images are focused in front of the rear of the eye due to the cornea being too steep or our eyes being to long. Makes this difficult to see far objects clearly. Hyperopia; farsightedness results when our cornea is too flat or our eyes are too short. Inability to see near objects clearly.

Question 33

What role does the retina play in vision?

Answer 33

Is able to absorb light, processes images and sends visual information to the brain, also contains the fovea.

Question 34

What is the function of the fovea? Where is it located?

Answer 34

Fovea; central part of the retina and is responsible for acuity, or sharpness of vision, has no receptor cells creating a hole, sour our brain fills in the gap.

Question 35

Can you describe what rods and cones are, what their functions are, and how they are different from one another?

Answer 35

Rods; receptor cells in the retina allowing us to see in low levels of light and peripheral vision. Cones; visual receptors that aid in daylight vision and colour vision.

Question 36

Where are cones most densely located? Where are the rods most densely located?

Answer 36

Both are found in the retina, rods are going to be more dense because they are long and narrow but also rely on low levels of light while cones require higher levels of light. But if we had too many cones the world would be blinding us continually.

Question 37

Where is the blind spot located? What is the blind spot?

Answer 37

The blind spot is where the optic nerve connects to the retina that contains no rods, cones, or sensory receptors.

Question 38

What is the Trichromatic Theory and how does it relate to colour perception?

Answer 38

Depends on the activity of three different = receptor types (red, green, blue). With three kinds of cones each maximally sensitive to different wavelengths of light.

Question 39

What is Opponent-Process Theory and how does it relate to colour perception?

Answer 39

Related to opposing responses by blue, yellow, red, and green. When we stare at one colour for too long we will begin to see other colors, coming from the visual cortex processing information from our rods and cones.

Question 40

What condition/effect does Opponent-Process theory explain well? What condition/effect does Trichromatic Theory explain well?

Answer 40

Opponent-Process Theory explains well the phenomenon of afterimages and the perception of color contrast. It suggests that color vision is based on three pairs of opposing color channels: red-green, blue-yellow, and black-white. When one color in a pair is stimulated, the other is inhibited. This theory helps explain why we see afterimages (e.g., staring at a red object and then seeing a green afterimage) and why certain color combinations seem to "cancel out." Trichromatic Theory explains well the detection of color at the level of the retina. It posits that color vision is based on three types of cone receptors, each sensitive to a different range of wavelengths: short (blue), medium (green), and long (red). This theory is particularly good at explaining how we initially perceive color based on the combination of input from these three types of cones, and is most effective for understanding color vision at the retinal level.

Question 41

What are the 3 different types of colour-blindness?

Answer 41

Monochromats; who only have one type of cones and thereby lose all color vision. Dichromats; they have two types of cones and are missing only one type. Trichromats; they have all four types of cones, all three colors plus an additional repeated one.

Question 42

What is Dual Process theory?

Answer 42

Dual Process Theory in color vision combines elements from both the Trichromatic Theory and the Opponent-Process Theory. It suggests that color vision operates through two stages:In short, Dual Process Theory integrates both theories, with Trichromatic Theory describing the initial detection of colors and Opponent-Process Theory explaining how the brain processes and interprets those colors at a higher level.

Question 43

What are feature detector cells? How do we know of the existence of feature detector cells (e.g., the work of Hubel & Weisel).

Answer 43

Feature detector cells are specialized neurons in the brain that respond to specific features of stimuli, such as edges, angles, motion, and orientation. These cells help process basic visual information that contributes to object recognition. The existence of feature detector cells was discovered through the work of Hubel and Wiesel in the 1960s. They conducted experiments on cats, recording electrical activity from individual neurons in the visual cortex. They found that some neurons responded strongly to specific features like vertical lines, while others responded to horizontal lines or particular orientations. This provided evidence that the brain processes visual information in stages, with specialized neurons detecting basic visual features.

Question 44

What are the components of sound that are responsible for our perception of auditory information? How do these components of sound affect what we hear?

Answer 44

Mechanical vibrations, sound waves are vibrations of molecules that travel through a medium, such as air, gas, liquids or solids. They are characterized by amplitude, wavelength and purity.

Question 45

What is frequency (pitch)?

Answer 45

Songs have pitch, which corresponds to the frequency of the wave. Higher frequency corresponds to higher pitch, lower frequency to lower pitch. This is also measured in hertz.

Question 46

What is amplitude?

Answer 46

Amplitude is the height of a sound wave corresponding to loudness, measured in decibels. The loud noise results in increased wave amplitude because more airborne molecules are vibrating.

Question 47

What is timbre?

Answer 47

Timbre refers to the quality, mixture, or complexity of the sound. Why human voices all sound different.

Question 48

What is the range of frequency the human ear can pick up?

Answer 48

20 to 20,000 Hz

Question 49

What is the interaction between pitch, amplitude, and pain.

Answer 49

The interaction between pitch, amplitude, and pain is as follows: Amplitude (loudness) determines how intense a sound is. High amplitude (loud sounds) can cause discomfort or pain, especially above 120 dB. Pitch (frequency) affects sensitivity; high-pitched sounds are more likely to cause discomfort at high volumes. Pain occurs when loud sounds (high amplitude) exceed a threshold, especially at higher frequencies, leading to hearing damage or discomfort. In short, loud, high-pitched sounds are more likely to cause pain.

Question 50

What are the three major components of the ear?

Answer 50

Outer, middle and inner ear

Question 51

What is the outer ear composed of?

Answer 51

Pinna and ear canal; helping funnel sound waves onto the eardrum.

Question 52

What is the middle ear composed of?

Answer 52

Ossicles; three tiniest bones in the body (malleus, incus, stapes) the ossicles will vibrate at the frequency of the sound wave, transmitting it from the eardrum to the inner ear.

Question 53

What is the inner ear composed of?

Answer 53

Cochlea converts vibration into neural activity. The inner cavity is filled with thick fluid. Vibrations from sound waves disturb this fluid and travel to the base of the cochlea where pressure is released and transduction occurs. The Organs of corti and basilar membranes are both inside the cochlea. They have hair cells that transduce auditory information based on how the fluid moves.

Question 54

What are the two main theories of pitch perception? Name and describe each.

Answer 54

Place theory- corresponds to the vibrations of different places along basilar membrane, accounting for perception of high pitched tones. Frequency theory- corresponds to the frequency the basilar membrane vibrates, and reproduces the pitch. (how many times a neuron fires-max 100x Hz)

Question 55

What are the two major types of deafness? How do they differ?

Answer 55

Conductive deafness is due to a malfunctioning of the ear, especially a failure of the ear drum or the ossicles of the inner ear. Nerve deafness is due to damage to the auditory nerve.

Question 56

What are common causes of hearing loss?

Answer 56

Loud sounds, can last a long time or are repeated, can damage our hair cells and lead to noise-induced hearing loss.

Question 57

What is olfaction?

Answer 57

Our sense of smell

Question 58

What is gustation?

Answer 58

Our sense of taste

Question 59

What is the gustatory system?

Answer 59

The gustatory system is a sensory system involved in analyzing various characteristics of food, such as its taste, texture, temperature, and pungency. It works in conjunction with other senses like vision and olfaction to perceive and evaluate the properties of food.

Question 60

What are the five basic tastes humans are sensitive to?

Answer 60

Bitter, salty, sweet, sour, umami

Question 61

How do humans detect taste?

Answer 61

With our taste buds on our tongues, papillae. These taste buds are able to separate between sweet, salty, sour, bitter and umami.

Question 62

What is the difference between nontasters, medium-tasters, and supertasters?

Answer 62

25% of people are supertasters, which are people who have extreme tastes in food (coffee is extremely bitter, normally picky eaters). Nontasters cannot taste most flavors of food. Medium tasters have a diverse planet and enjoy a variety of flavors.

Question 63

What are some olfaction disorders?

Answer 63

Damage to the olfactory nerve along with diseases like parkinsons and alzheimers can damage our ability to perceive taste and smell.

Question 64

What are pheromones?

Answer 64

Odorless chemicals that serve as social signals to members of one's species- altering sexual behavior.

Question 65

What is flavor?

Answer 65

We analyze how something tastes by how it smells, parts of our limbic system, such as the amygdala, help us distinguish flavor. Activates the gustatory cortex once our body has a reaction to the smell of the food to anticipate the flavor.

Question 66

What is the somatosensory system?

Answer 66

Our sense of touch, temperature, and pain.

Question 67

What are the four main components of the somatosensory system? Describe each.

Answer 67

Our somatosensory system will respond to stimuli applied to the skin, such as light touch or deep pressure, hot or cold, sometimes our body can localize pain in different locations-heart attacks the left arm through the shoulder will cause pain.

Question 68

What is the vestibular sense?

Answer 68

Our sense of equilibrium and balance. Our senses of body position and balance work together.

Question 69

What are the different layers of skin called?

Answer 69

Surface level- Skin surface, skin layers, pressure-sensitive nerves, meissner's corpuscle, sweat gland Subsurface Level- Subcutaneous fat, blood vessels, pacinian corpuscle, ruffini ending.

Question 70

What are mechanoreceptors?

Answer 70

We sense light touch, deep pressure, and temperature with mechanoreceptors, specialized nerve endings located on the ends of sensory nerves in the skin.

Question 71

Describe the withdrawal reflex.

Answer 71

Often touch and pain information activates local spinal reflexes before traveling to brain sites dedicated to perception. In some cases, painful stimuli trigger the withdrawal reflex. When we touch a fire or hot stove, we pull away immediately to avoid getting burned. After activating the spinal reflexes, touch and pain information travels upward through parts of the brainstem and thalamus to reach the somatosensory cortex.

Question 72

What is the Gate Control theory of pain?

Answer 72

Idea that pain is blocked or gated from consciousness by neural mechanisms in the spinal cord. Can account for how pain varies from situation to situation depending on our psychological state.

Question 73

What is Nociceptive pain? What is Inflammatory pain? What is Neuropathic pain?

Answer 73

Nociceptive pain is from injury. Inflammatory pain is from swelling or infection. Neuropathic pain is from nerve damage.

Question 74

What are the differences between the A-delta pathway and the C-fibre pathway?

Answer 74

Pain signals transmitted to the brain via two types of pathways that pass through different areas in the thalamus. Fast pathway (A-delta pathway), slow pathway (C fibre pathway).

Question 75

What is the Proprioceptive system?

Answer 75

Also called our kinetic sense, helps us keep track of where we are and move efficiently. Sense of out body position.

Question 76

What are the two types of proprioceptors?

Answer 76

Stretch receptors embedded in our muscles and force detectors embedded in our muscle tendons. Proprioceptive information enters the spinal somatosensory and motor cortices. Therefore our brain combines information from our muscles and tendons, alongside with a sense of our intentions, to obtain a perception of our bodies location.

Question 77

What is the Vestibular system?

Answer 77

System responds to gravity and keeps you informed of your body’s location in space

Question 78

What makes up the Vestibular system?

Answer 78

Inner ear in the semicircular canals are filled with fluid that helps sense equilibrium and maintain our balance. Vestibular information reaches parts of the brainstem that controls eye muscles and triggers reflexes that coordinate eye and head movements. Vestibular information also travels to the cerebellum, which controls bodily responses that enable us to catch our balance when we are falling.

Question 79

What Is parallel processing?

Answer 79

Ability to attend to many sensory modalities simultaneously (process the big picture)

Question 80

What is bottom-up processing? Give an example. is top-down processing?

Answer 80

Bottom-up processing- we construct a whole stimulus from its parts (stimulus drivenTop-down processing- influences what we perceive due to our beliefs, expectations, and past experiences (conceptually driven)

Question 81

What is perceptual constancy? Give an example.

Answer 81

The process by which we perceive stimuli consistently across varied conditions.as an example of a door because we can consider viewing a door from shut, barely opened, or fully opened, even though these shapes look almost nothing like each other. (shape constancy)

Question 82

What are perceptual sets?

Answer 82

Size constancy, shape constancy, colour constancy

Question 83

What Is size constancy?

Answer 83

Our ability to perceive objects as the same size no matter how far away they are from us.

Question 84

What Is colour constancy?

Answer 84

Our ability to perceive colour consistently across different levels of lighting.

Question 85

What Are the Gestalt Principles?

Answer 85

Are rules governing how we perceive objects as whole within their overall context. Gestalt principles of perception help to explain why we see much of our world as consisting of unified figures or forms rather than confusing jumbles of lines and curves. These principles provide a road map for how we make sense of our perceptual worlds.

Question 86

What is motion blindness?

Answer 86

Is a disorder when paitents cant seamlessly string still images processed by their brains into perception of ongoing motion. The disability can affect simple daily tasks, like crossing the road.

Question 87

Name and describe the six main Gestalt Principles of perception.

Answer 87

Proximity- objects close to each other tend to be perceived as unified wholes. Similarity- all things being equal or patterns. Continuity- we perceive objects as whole, even if the other objects block part of them. Closure- when partial visual information is present, our brains fill in what's missing. Symmetry- we perceive objects that are symmetrically arranged as whole more often than those that aren't. Figure-ground - perceptually, we make an instantaneous decision to focus attention on what we believe to be the central figure. ( the pictures with two images in it)

Question 88

What is the Phi Phenomenon?

Answer 88

Discovered by Max Wertheimer, is the illusory perception of movement produced by the successive flashing of images.

Question 89

What is depth perception?

Answer 89

The ability to judge distance and three-dimensional relations.

Question 90

What are the two kinds of cues used to gauge depth?

Answer 90

Monocular depth cues; ability to judge depth with one eye, binocular depth cues; ability to judge depth with both eyes.

Question 91

What are the two kinds of monocular depth cues? Explain and describe each one?

Answer 91

Relative size; all things being equal, more distant objects lokk smaller than closer objects. Texture gradient; the texture of objects becomes less apparent as objects move farther away.

Question 92

What are the two main binocular depth cues? Describe each.

Answer 92

Binocular disparity; objects project images to different locations on the right and left retinas. Binocular convergence; eyes converging toward each other as they focus on closer objects.

Question 93

What are some common visual illusions humans are susceptible to? (add image)

Answer 93

Linear perspective, texture gradient, introspection, relative size, height in plane, light and shadow.

Question 94

What is auditory localization?

Answer 94

Auditory localization is the ability to identify the location of a sound source in space. It relies on cues such as differences in loudness, timing, and pitch between the two ears. The brain uses these cues to determine the direction and distance of a sound, helping us perceive where it is coming from.

Question 95

What Is Subliminal perception?

Answer 95

The perception below the limen, or the threshold of consciousness.watching TV causally an ad comes up and extremely quick flashes of light on a screen, only a few minutes later, you’re resized with an uncontrollable desire to eat a cheeseburger.

Question 96

What Is Subliminal persuasion?

Answer 96

Subliminally presented words related to thirst, such as drink, may slightly influence how much people drink, but specific words related to brand names, such as cola, don't influence beverage choice.