PSYC 2nd Midterm

achromatopsia

lack of colour vision; can’t see or remember colours

synesthesia

colour associated with things

monocular depth cues

percieved with one eye

binocular depth cues

perceived using both eyes

occlusion (interposition)

blocking object is closer than the blocked object

relative & familiar size

the person who is bigger than the other people is closer

relative height

the higher object looks further away

texture gradient

the further away the smoother the ground

aerial perspective (haze)

closer objects appear clearer and further seems hazy

linear perspective

parallel lines converge as they go further in the distance

shading and shadow

attached shadow: shading pattern distributed across an object; provides 3D info

cast shadow

falls on the surface surrounding object in light path

pictorial cues

depth cues depicted in a static 2D image

non-pictorial cues

require additional information (e.g. movement) or physiological responses of eyes beyond static image

motion parallax

far objects move the same direction, close objects move opposite way

accommodation

objects closest to you make your eyes converge- the vergence angle will change when object is farther or closer

binocular depth cues

binocular disparity: difference in the retinal images of two eyes that provide information about depth

binocular rivalry/suppression

images in the left and right retinas will compete for conscious perception

ames room illusion

when viewed through a peephole, the person on the left look much smaller than the one on the right

parallel processing

different features are processed and the brain deals with them simultaneously

binding problem

we do not know how the brain combines different visual features to make a single perception of an object

perceptual constancy

image on retina can be vastly different at these pictures, but we still know that they are showing the same object

frequency

perception of pitch (low- low-pitch; high- high pitch)

amplitude

loudness (high amp- loud; low amp-soft sound)

complexity

perception of timbre (quality)- (simple-pure tone; complex-mix of frequencies)

McGurk effect

what we see overrides what we hear

multisensory perception

stimulating multiple senses (e.g. auditory and visual) at the same time e.g. visual thunder and sound

tactile agnosia

inability to identify objects by touch

2 brain pathways for pain receptors

somatosensory cortex (processing pain) and limbic system (processing emotional responses)

gate-control theory

signals arrive from pain receptors but stopped/gated by interneurons in the spinal cord- rubbing a sore spot

transcutaneous electrical nerve stimulation (TENS)

a commercial method based on gate control theory

anesthetics

produce total loss or sensation by interrupting signals travelling to brain

analgesics

produce total loss of pain sensation only (e.g. non-opiate and opiate) eg. tylenol or advil

peripheral nervous system: 4 different-sized nerve fibres

proprioceptor, mechanoreceptor, pain and temperature, pain, temperature and itch

proprioceptor

muscle sense reflexes

mechanoceptor

non painful touch; pressure

proprioception

sense of body position

vestibular system

three fluid-filled semicircular canals (inner ear)- supports balance and spatial orientation through visual input

vestibulo-ocular reflex

helps you maintain balance and stable perception even though your head and eyes are constantly moving

olfactory sensory neurons

have axons and fire action potentials

odour

sensation associated with stimulation of olfactory system

odourant

odour-inducing chemical; small, volatile molecule, repellent to water and fat molecule

piriform cortex

primary pathways for olfactory percepion

detection

percieving something is there

recognition

knowing you have smelled it before

discrimination

determining if there is a difference between things

identification

attaching a verbal label to the smell

asmosia

inability to smell; caused by infection, disease or drugs

parosmia

abnormally unpleasant odours

taste (gustation)

sensations caused by substances that dissolve in saliva and penetrate taste buds on the tongue

taste buds

located in the tiny bumps (papillae) covering the tongue

flavour

multi-modal sensations; stimulates receptors for taste, touch, and smell

psychophysics

measuring conscious perception

absolute threshold

the minimal amount of stimulation necessary to detect presence of stimulus e.g. dot trial

psychometric function

a graph of stimulus intensity on the horizon axis versus the subject’s responses (e.g. yes or no) on vertical axis

suprathreshold

above absolute threshold (both stimuli are detectable)

difference threshold

the smallest difference between stimuli or change in a stimulus that the observer noticed 50% of the time (also called JND)

consciousness

a person’s subjective experience of the mind and the external world (events, objects, changes etc.)

four basic properties on consciousness

intentionality, unity, selectivity and transience

minimal consciousness

low-level kind of sensory awareness and responsiveness that occurs when the mind input sensations and output behaviour eg. sensing sunlight and turning towards it

full consciousness

know and are able to report your mental state e.g. being aware when you are in pain

self-consciousness

distinct level of consciousness in which attention is drawn to self e.g. being embarassed

binocular rivalry

two dissamiliar images are presented simultaneously to each eye, and your conscious perception alternates

inattentional blindness

failure to percieve objects that are not focus of attention

innattentional deafness

failure to notice a fully-audible, but unexpected, sound because attention was focused on a different sound

change blindness

people fail to detect changes to the details of a scene

attention

ability to focus on specific things or locations

interocular suppression

an image is presented to one eye suppresses another image presented to other eye

blindsight

people who cant see have unconscious mind that guides behavior correctly (when forced makes correct guesses)

hemispatial neglect

defecit in attention to awareness of one side of visual field (contralesional)- brain defecit not visual

egocentric neglect

one side of the patient is ignored

allocentric (object-centered) neglect

one side of object ignored

hemispatial neglect in different perceptual domains

motor (failure to move one side of body), tactile (cannot feel touch on one side), auditory (inattention to sound on one side)

extinction

can detect something on their weaker contralesional side when alone but fail to notice with something else

balint syndrome

caysed by bilateral damage to parietal cortex, impaired spatial awareness, attention and coordination between vision and movement

stimultagnosia

everything except the current object of attention seems to be blocked from conscious perception

mind wandering

a state of consciousness in which random flow of thoughts come to mind

experience sampling

participants are asked “at random intervals) to report states “did I mind wander”

default mode network (DMN)

activations of brain areas when people daydream

attention network

more active during tasks- uses engaged attention

freudian slip

when an unconscious thought is suddenly expressed at an inappropriate time or in an inappropriate social context

modern take on freudian slips

some might indeed reveal unconscious thoughts and desires as simply cases of misremembering, mis-retrieval, lapses or language mistakes

priming

when the response to a stimulus is influenced or facilitate by recent experience with that stimulus or a related stimulus

subliminal perception

when stimulus are processed by sensory systems but do not reach consciousness, because of short duration or subtly

altered state of consciousness

sleep, dreaming, drug use, injuries

stage 1

“dozing off” stage. theta waves

stage 2

light sleep (relaxed muscle, eye movement stops, heart rate slows). sleep kindles and k-complex

stage 3

deep sleep (harder to wake up). delta waves

stage 4

deeper sleep

REM sleep

brain activity increases, eyes dart around quickly. dream

freud’s view on dreams

dreams hold meaning (they represent hidden wishes or anxiety)

activation-synthesis model

the brain imposes meaning on random neural activity

psychoactive drugs

chemicals that influence consciousness or behavior by altering the brain’s chemical message system

drug tolerance

tendency for larger doses of a drug to be required overtime achieve the same effect (longer you take, more you need)

physical dependance

unpleasant physiological symptoms (e.g. pain, convulsions or hallucinations) accompanying withdrawal from drug use

psychological dependance

desire to return to drug even when physical symptoms are gone

depressants

reduce CNS activity; increase activity of the neurotransmitter GABA alcohol

expectancy theory

alcohol effects can be produced by people’s expectations of how alcohol will influence them in particular situations

alcohol myopia theory

alcohol hampers attention, leading people to respond in simple ways to complex situations

stimulants

substances that excite the CNS heightening arousal and activity levels. increases dopamine and norephedrine