psy2012 ch5 sensation and perception

Distinguish between bottom-up and top-down processing.

-Bottom-up processing: perception based on physical features of the stiumulus ex: recognize a grapefruit squirt based on your experience of the strong scent, cool moisture and sharp taste -Top-down processing: how knowledge, expectations, or past experiences shape the interpretation of sensory information -what we expect to influences what we percieve ex: unlikely to see a blue, apple-shaped object as a real apple because we know from past experiences that apples are not blue

Describe the key difference between monocular and binocular depth cues.

-Monocular depth cues are available to each eye alone, while binocular depth cues arise from the fact that people have two eyes. -Binocular and monocular depth cues permit the perception of depth from a two-dimensional retinal image. Visual illusions can arise when the eye receives conflicting evidence - for example, a size cue that does not agree with a distance cue.

Color blindness

1. Red-green color blindness (more common) Includes deuteranomaly (green cone photopigment is abnormal) & protanopia (no working red cone cells) 2. Blue-yellow color blindness Includes tritanopia (lack blue cone cells) Genetic disorders more common in males (~8 %) than females (<1%) Third extremely rare type: cone or rod monochromacy

Explain the concept of a sensory threshold. Distinguish between absolute threshold and difference threshold.

A sensory threshold is the level of strength a stimulus must reach to be detected. Psychologists study sensory thresholds to learn how humans and animals process sensory information. -Absolute threshold is the minimum detectable amount of energy required to activate a sensory receptor. -Difference threshold is the amount of energy change necessary for a sensory receptor to detect a change in stimulation.

Define audism and discuss the controversy around cochlear implants.

Audism: discrimination that is based on a person's ability, or lack of ability, to hear. -Individual level -Systemic, or institutional level -What about the language in your textbook? "When devices are implanted in children born deaf, the child's hearing will be quite functional and he or /she will learn to speak reasonably normally."

*Dimensions of color

Categorize color along 3 dimensions: 1. Hue: the distinctive characteristics that place a particular color in the spectrum 2. Saturation: the purity of the color 3. Brightness: the color's perceived intensity -The lightness of a visual stimulus is determined by the brightness of the stimulus relative to its surroundings.

Identify three components of your sense of touch.

Components of your hepatic sense: 1. Pain 2. Pressure 3. Temperature

*Define and provide examples of the five basic taste sensations.

Every taste is composed of a mixture of 5 basic qualities: 1. Sweet: pleasures, sweetness signals the presence of sugars, the foundation of the food chain and a source of energy 2. Sour: mouth-puckering sensation is caused by acids ex: lemons, yogurt and sourdough bread 3. Salty: brains programmed so little salt tastes good, lot tastes bad. ensures we consume just enough to maintain the salt balance our bodies need to function. 4. Bitter: A poison alarm, bad taste accompanied by a reflexive "yuck" expression. ex: kale, dark chocolate and coffee. 5. Umami (Japanese for "savory" or "yummy"): produced by certain amino acids. It's best described as "savory"—a taste rich in flavor released by cooking, curing or aging ex: cured meats, aged cheeses, fish sauce, green tea, soy sauce and cooked tomatoes. 6. Monosodium glutamate (MSG): flavor enhancer

Identify and differentiate among the Gestalt principles of perceptual organization.

Gestalt principles of perceptual organization describe innate brain processes that put information into organized wholes. The Gestalt perceptual groupings are proximity, similarity, continuity, closure, and illusory contours. 1. Proximity: If things are close to eachother, you assume they are part of the same image 2. Closure: When your brain fills in gaps, like the dog made out of spots 3. Similarity: You see things as the same if they are similar looking 4. Good continuation: When things intersect, we see them as part of the same thing Common movement: When things move in the same direction at the same rate, we group them together.

*Describe the neural pathway for smell.

Olfaction: sense of smell Olfactory epithelium: a thin layer of tissue, within the nasal cavity, that contains the receptors for smell 1. stimuli: odorants pass into your nose and naval cavity 2. receptors: olfactory receptors in olfactory epithelium transmit the signal to the olfactory bulb, which transmits.. 3. pathway to the brain: along the olfactory nerve to areas of the cortex and amygdala 4. resulting perception: as a result you know the smell is good or bad and mat even experience memories related to the smell

*Distinguish between the two types of pain (and their fibers) - be able to identify examples of each.

Pain receptors are located all over the body, but most pain is signaled by haptic receptors in the skin. 1. Fast fibers: sharp, immediate pain (activated by strong physical pressure and temperature extremes) Ex: 2. Slow fibers: chronic, dull, steady pain (activated by chemical changes in tissue when skin is damaged) myelinated axons: send info quickly nonmyelinated axons: send info slowly

Distinguish between qualitative versus quantitative sensory information.

Qualitative information: consists of the most basic qualities of a stimulus (is it green or red?) Ex: Having tea, from coffee. Beef or Soy burger Quantitative information: consists of the degree, or magnitude (is it bright or dim?) Ex: Degree of heat you feel in your mouth. Sense of vision, smell, sight. is this cooked rare, medium, medium well done... etc

Explain signal detection theory and sensory adaption.

SDT: a theory of perception based on the idea that the detection of a stimulus requires a judgment and is not an all-or nothing process. -Shaped by expectations, rewards/costs associated with detecting/not -Ex: people who read scans MRI/Cat scans. The importance of them picking up on abnormalities is really really high. -Sensory adaptation occurs when sensory receptors stop responding to unchanging stimuli. The brain integrates diverse neural inputs to produce stable representations.

Distinguish between sensation and perception.

Sensation: The detection of external stimuli and the transmission of this information to the brain Perception is our conscious experience of those stimuli, the processing, organization, and interpretation of sensory signals.

*Define and give an example of synesthesia.

Stimulation of one sensory or cognitive pathway leads to automatic paired experience in a second sensory or cognitive pathway. Ex: Most common type: grapheme-color synesthesia (letters or numbers are perceived as inherently colored).

Describe the trichromatic theory of color vision.

The theory that the sensation of color results because cones in the retina are especially sensitive to red light (long wave-lengths), green light (medium wavelengths), or blue light (short wavelengths).

Describe how sensory information is translated into meaningful stimuli.

Transduction is the process by which sensory stimuli are translated into signals the brain can interpret. Transduction occurs at sensory receptors, specialized cells in each sense organ. Sensory receptors send messages to the thalamus, which sends projections to cortical areas for perceptual processing.

Describe and be able to apply Weber's law to examples.

Weber's law: The just noticeable difference between two stimuli is based on a proportion of the original stimulus rather than on the fixed amount of difference. -Ex: (If you had one candle you would notice the change in brightness if you add another, but you wouldn't notice if they added one more to a group of 100 candles.) -Ex: Hershey kisses

Zach and David decide to go exploring the forest behind their farm on a cold December day. The fact that they felt much colder when they initially got outdoors than they do five minutes later, despite having not done anything to warm themselves, is known as: a. Sensory adaptation b. Sensory threshold c. Convergence d. Just noticeable difference

a. Sensory adaptation

In visual processing, ventral is to dorsal as: a. what is to where. b. where is to what. c. superior is to inferior. d. both B and C.

a. what is to where.

Identify the two main components of sound waves that influence our perception of a sound.

amplitude: determines loudness --> louder sound frequency: determines pitch --> higher pitch -measured in Hertz, vibrations per second

Javier's attention is captured by the loud sirens and bright lights of an ambulance as it passes by. Arezou's attention is captured when she hears someone say her name. Javier's response is best explained as a result of ________ , while Arezou's response is best explained as a result of ________. a. top-down processing; bottom-up processing b. bottom-up processing; top-down processing c. qualitative information; quantitative information d. quantitative information; qualitative information

b. bottom-up processing; top-down processing

With respect to the properties of the sound wave, a higher-pitched sound is one that is higher in ________, a louder sound is one that is higher in _______. a. decibels; hertz b. frequency; amplitude c. amplitude; frequency d. timbre; pressure

b. frequency; amplitude

You are standing at the intersection of two perpendicular roads. You see one road running north-south and another road running east-west. You do not see one road running north and then turning east and another road running east then turning north. Which Gestalt principle accounts for what you do and do not see? a. similarity b. good continuation c. parallelism d. closure

b. good continuation

Anna is reading her psychology text. The activation of receptors in her retina is called ________; her interpretation of the stimuli as particular words is termed ________. a.sensation; sensation as well b. sensation; perception c. perception; sensation d. perception; perception as well

b. sensation; perception

If you close one eye, you will still be able to use ________ as a depth cue, but you will not be able to use ________ as a depth cue. a. linear perspective; occlusion b. texture gradients; disparity c. convergence; motion parallax d. disparity; linear perspective

b. texture gradients; disparity

As part of an experiment, Amanda is seated in front of a blank computer screen. On each trial, a line appears on the screen and then an object appears above the line. The task is to name the object as rapidly as possible. The object is either presented alone or within a scene. For example, a chicken may be presented alone or in a barnyard. People are significantly faster at naming the object when it is presented in the scene. This result is evidence for: a. bottom-up processing in visual perception. b. top-down processing in visual perception. c. the role of context in figure-ground segmentation. d. a cognitive application of the Gestalt laws.

b. top-down processing in visual perception.

Days after breaking his nose in a football game, Ben still perceives a dull pain in his nose. The dull ache travels along ________ pain fibers, which are ________. a. fast; unmyelinated b. fast; myelinated c. slow; unmyelinated d. slow; myelinated

c. slow; unmyelinated

________ states that the more intense the original stimulus, the greater the change in intensity required to produce a just noticeable difference. a. Matching law b. Sensory adaptation c. Signal detection theory d. Weber's law

d. Weber's law

After being in a car crash, Yuri has the selective inability to recognize faces. He is most likely suffering from ________ due to damage to his ________. a. agnosia; primary visual cortex b. agnosia; fusiform gyrus c. prosopagnosia; primary visual cortex d. prosopagnosia; fusiform gyrus

d. prosopagnosia; fusiform gyrus

Describe the function of the fusiform gyrus and explain what happens if this area is damaged (prosopagnosia).

fusiform gyrus: the visual perception of faces activated in area of the brain prosopagnosia: the inability to recognize faces

Describe the process of gustation.

gustation: sense of taste 1. bite into something, molecules dissolve in fluid on your tongue and received by papillae and taste buds 2. receptors: taste receptors in taste buds transmit signal of taste receptor to nerve fiber 3. pathway to brain: along a cranial nerve, through the thalamus, to other areas of your brain (thalamus) 4. resulting perception: as a result, you know the taste is good or bad

Name the part of the brain involved in the process of olfaction that is also involved in emotion and memory and that is involved in deciding if a smell is pleasant or not.

information about whether smell is pleasant or unpleasant is process in the brain's prefrontal cortex intensity of smell is involved in emotion and memory olfactory stimuli can evoke feelings and memories

Describe what the vestibular system is involved in.

perception of balance (determined by receptors in the semicircular canals of the inner ear).

Describe the function of the two types of sensory receptors in the retina.

rods and the cones, and they differ in their shape, number, function, location, and links to the brain. -When light enters the eye, it triggers a photochemical reaction in the rods and cones, which in turn activates bipolar cells. -The bipolar cells activate ganglion cells, and their axons (combined to form the optic nerve) transmit information (via the thalamus) to the visual cortex in the brain's occipital region. -The more numerous rods, located mainly around the periphery of the retina, are more sensitive to light. -Multiple rods send combined messages to a bipolar cell, and this pool of information lets us see rough images in dim light. -Cones, concentrated in the fovea (at the center of the retina), are sensitive to color and detail. -A cone may link directly to a single bipolar cell,and this direct line to the brain preserves fine details in the cone's message.

Know which part of the brain is not involved in the process of olfaction that is involved with all other senses.

smell signals bypass the thalamus, the early relay station -smell receptors transmit information directly to olfactory bulb: the brain center for smell, located below the frontal lobes

Identify and explain the what and where pathways.

theory that visual areas beyond primary visual cortex form two parallel processing streams, or pathways 1. lower ventral system(what): specialized in perception and recognition of objects ex: determining colors and shapes 2. upper dorsal system(where): specialized in spatial perception ex: where object is and relating to other objects in scene