PSYC Midterm 2 Flashcards

Question

5 Misconceptions of Heritability

Answer 1

1. Applies to a single individual rather than differences among individuals 2. Tells us whether a trait can be changed by environmental factors: heritability says nothing about how malleable a trait is. -Environmental changes can impact everyone in population, but heritability is not involved -Reaction Range: extent to which genes set limits to how much a trait can change in a new environment. (IQ high vs Eye color low) 3.Fixed number: heritability is the relative influence of genes compared to environment on individual differences in a trait or behavior in a given population at a given point in time. 4. Is the same for everybody across the whole population: different heritability in IQ between rich & poor 5. Implies destiny & only hope is to alter genes

Answer 2

Epigenetics: heritable changes in phenotype in the absence of changes in DNA sequence, caused by modification of gene expression/readability GxE Interactions: Nurture & Nature are interactive & additive. Phenotypic effect determined by interaction between environment & genes -On a graph lines representing different genotypes would intersect at a specific environment & grow farther apart when environment becomes more extreme (depression increasing in increasing stressful environments) or vice versa (speed of trained & untrained rats closing in together in increasingly enriched environments) showing interaction between environment & gene, how they multiply with each other to create overall greater phenotypic variability

Answer 3

Sensation: the stimulation of the sense organs Perception: the selection, organization, identification, filling in gaps & interpretation of sensory input in order to form a mental representation Actions can lead to perceptions & vice versa. Gun embodiment effect.

Answer 4

Transduction: process in which specialized sensors in the body convert physical signals from the environment into encoded neural signals sent to the CNS Sensory Adaptation: gradual decline in sensitivity due to prolonged stimulation

Answer 5

Absolute Threshold: lowest level of stimulus needed to detect its presence 50% of the time starting from 0 Noticeable Difference: smallest change in intensity of a stimulus that one can detect -Weber’s Law (linear): the change in a stimulus that will be just noticeable is a constant ratio of the original stimulus -Fechner’s Law (logarithmic): magnitude of perceived intensity increases proportionally to the logarithm of the stimulus intensity = increases at increasing rates -Steven’s Law (both): different relations for different stimuli Signal Detection Theory: becomes harder to detect a signal as background noise increases Response Biases: tendency to make one type of guess over another when a weak signal is present or absent under noisy conditions Specific Nerve Energies: experience of sensation is by the nature of the sense receptor not the stimulus, vulnerable to cross-talk between senses (Synthesia)

Answer 6

Attention: must be able to focus on one task’s sensory input ignoring all others & must be prepared to use sensory information that signals a potential threat Selective Attention: reticular activating system & forebrain selects on sensory input & turns off or down others Inattentional Blindness: poor at detecting stimuli in plain sight when our attention is focused elsewhere Binding Problem: how does our mind seamlessly combine many different senses into a unified perception (ex. Apple=sweet, juicy, red, shiny, smooth, etc.). Inability to do this visually is Visual Agnosia

Answer 7

Parallel Processing: attending to many sense modalities simultaneously Bottom Up: begins with perception of raw stimuli & ends with our synthesizing them into a meaningful concept = unknown→known = primary visual cortex → association cortex Top Down: beings with beliefs & expectations which are imposed onto raw stimuli = association cortex → primary visual cortex

Answer 8

Functions of Eyeball: channel light to the retina & house retina Cornea: curved transparent layer bending light to focus image to eye Pupil: hole that light enters Iris: colored ring of muscle surrounding & controlling pupil regulating amount of light entering eye for both eyes simultaneously Sclera: white part maintains ball shape → Lens: bends light Accommodation: adjustment of the curvature of the lens to alter visual focus. Loss of flexibility of lens presbyopia. Farsighted(long lens+ball)=far yes, close no. Nearsighted(flat lens+ball)=far no, close yes Retina: neural tissue lining inside back surface of the eye that absorbs light & processes light & sends info to the brain Optic Disk: blind spot hole in the retina where Optic Nerve exits the eye Optic Nerve: ganglion cells that bundle all their axons together depart the eye to reach the brain & fork at the optic chiasm, half fork the other stays on same side Optic Chiasm: inside half of each eye cross over & projects to opposite hemisphere of brain allowing for binocular vision Thalamus → Primary Visual Cortex or Secondary Visual Cortex & Tertiary visual cortex in midbrain

Answer 9

Cones: visual receptors in daylight vision & color vision Fovea: tiny spot at center of retina containing only cones Rods: visual receptor in night vision & peripheral vision Photopigments: chemicals that change following exposure to light. Dark & Light Adaptation: eyes become more sensitive to light in low illumination & less sensitive to light in high illumination Receptive Field: collection of rods & cones that funnel signals to a particular visual cell, when stimulated this field affects the firing of the visual cell, pays attention to edges On Center: center=EPSP, outside=IPSP Off Center: center=IPSP, outside=EPSP

Answer 10

Feature Detectors: neurons that respond selectively to very specific features of more complex stimuli (research by Hubel & Wiesel cats neuron firing with certain light shape, size, width & orientation, movement) → our ability to use certain minimal patterns to identify objects -Simple Cells: respond best to lines of correct width, orientation, & location in receptive field -Complex Cells: respond best to movement of lines a specific direction Goal of Visual Perception: navigate our environment, reconstruct 2D-3D can make mistakes Higher Cortical Regions: process more complex shapes

Answer 11

Trichromatic Theory: additive mixing of 3 colors (blue, green red) as cones are only sensitive to these wavelengths of light which create all colors humans can see Subtractive color mixing: pigments Opponent Process Theory: we perceive colors in terms of three pairs of opponent cells: red or green, blue or yellow, and black or white, color perception also depend on receptors that make antagonistic responses to 3 pairs of color, inhibiting certain colors & processing others to create the color one sees Color Blindness: one or more of the color cone cells are absent, not working, or detect a different color than normal After Images-Combining both theories: Cones get tired from inhibiting red & processing green that eventually only sees red wavelengths from white screen.

Answer 12

Binocular Cues: clues about distance based on the differing views of the two eyes -Retinal Disparity: objects project images to slightly different areas in each eye -Convergence: sensing the eyes converging towards each other as they focus on closer objects Monocular Cues: clues about the distance based on the image of one eye -Motion Parallax: depth cues from difference in rate of movement of objects at different distances across retina -Pictorial Depth Cues: clues about depth that can be given in a picture: Linear perspective, texture gradients, interposition, relative size, height in plane, light & shadow

Answer 13

Size/Depth Perception: objects same size although far away, mentally enlarging far away figures Shape Constancy: see a door as a door even when shut, open & fully open although shapes look nothing alike -Distal Stimuli: stimuli that lie in the distance = the actual physical stimulus, the physically objective dimensions of the viewed object Hollow face, black & white checkerboard -Proximal Stimuli: stimulus energies that impinge directly on the sensory receptors = image that falls on the retina Looks like an actual 3D face, some of the tiles are the same shade of grey -Perceptual Hypothesis: an inference about which distal stimuli could be responsible for the proximal stimuli sensed -Subjective Contours: brain providing missing information about outlines Color Constancy: perceive color consistently across different levels of lighting

Answer 14

3 Different body senses: 1. Skin touch, temperature, & chemical/mechanical injury 2. Body Position 3. Balance Touch (informs of immediate surroundings) travels faster than pain (alerts us to take care of injuries that can wait) info

Answer 15

1. Somatosensory System: touch & pain, multiple stimulus, all nerve endings unevenly distributed across our body surface most in fingertips, fewest in back -Mechanoreceptors: specialized nerve endings located on the ends of sensory nerves in the skin: light touch or deep pressure -Free Nerve Endings: more plentiful, touch, temperature: hot or cold & pain from Chemical or Mechanical Injury 2. Proprioception: body position sense, kinesthetic sense, efficient movement, keep track of where we are -Proprioceptors: sense muscle stretch & force → brain stem → thalamus → somatosensory & motor cortices combines info+intentions=perception of body’s location -Stretch Receptors: embedded in our muscles Force Detectors: embedded in muscle tendons 3. Vestibular Sense: balance, equilibrium -3 Semicircular canals: filled with fluid snes equilibrium & help maintain balance, coordinate eye & head movements, info to cerebellum to control bodily responses to rebalance -Dizziness: mismatches of balance between vestibular sense & visual inputs

Answer 16

1. Traditional theories of pain outdated: pain results from the transmission of pain signals from the site of injury to the brain, amount of pain experienced is directly proportional to the amount of tissue damage 2. Gate Control Theory of Pain: pain gate in the spinal cord can open & close to modulate the experience pain determined by psychological factors & context (soldier vs civilian) -Open: physical-extent of injury, emotional-anxiety, cognitive-boredom -Close: physical-medication, emotional-relaxation, cognitive-distraction -Physical, emotional & cognitive factors all interact

Answer 17

Warns us of potential danger to tissue harm or to the presence of injury Facial expressions, body movements & vocalizations

PSYC Midterm 2 Flashcards

(41 cards)