Sensation

AP psychology

sensing

you noticing stimuli

perceiving

your brain interpreting the sense data

bottom up

beginning with the stimulus, using the stimulus themselves as your guide

top down

using information you already know to help understand and organize stimuli

receive info, transduction, deliver info to brain

steps to basic sensory systems

changes signal to neural impulse

transduction

absolute threshold

when you notice stimuli >50% of the time, aka edge of awareness

subliminal threshold

when you notice stimule <50% of the time

difference threshold

how much change is needed in a stimuli for one to notice there is a change in the stimuli

Ernst Weber

law which says there is a % change in which you will notice a change in a stimuli

physiology, strength and presence of stimuli, psychological state

factors that determine the absolute threshold for any particular stimuli

psychological state

anxious, emotions, experiences, motivations

sensory adaptation

you get “used” to a stimuli

sensory adaptation

this allows us to pay attention to a new stimuli

sensory interaction

the way your senses work together to help you understand the world

sensory interaction

taste, understanding people talking to you

synesthesia

experiencing one sensory input via another sense

rods

on the periphery of the eye

rods

detect movement, not color

rods

help with light/dark adjustment

retina

tissue full of photosensitive cells

retina

its job is to capture light and its transducer to the brain for processing

fovea

where visual acuity is the highest

blind spot

where the visual nerve connects to the eye, not photosensitive cells, brain fills in the gap

lens

focuses light onto the retina

accommodation

the process of the lens focusing light onto the retina

lens

problems (near and far sightedness) occur if accommodation is faulty here:

cone cells in the retina

are responsible for color vision

trichromatic, opponent process

theories of color vision:

trichromatic

you have cones that are able to detect one of three colors of light, Red, Green, Blue, we combine these to see colors

red

long wave length

green

medium wavelength

blue

short wavelength

opponent process

cone cells that can see only one of a pairs of colors at a time

red green, blue yellow, white black

ganglion cell pairs in the opponent process theory

opponent process

after image can be explained by the:

eye, brain

color vision problems can occur in:

dichromatism, monochromatism

color vision problems in the eye itself:

dichromatism

only see 2 of 3 color pairs

monochromatism

see shades of grey

occipital lobe

problems in colors vision in the brain occur in the:

prosopagnosia, blindsight

problems in color vision in the occipital lobe:

Prosopagnosia

when you cannot recognize faces

blindsight

blind but able to detect movement

sound

air molecules moving in waves

amplitude

loudness

wavelength

pitch

place, frequency, volley

theories of pitch perception

place

different pitches are detected by different parts of the ear

frequency

different pitches are detected because they cause different speeds of vibration

volley

different pitches are detected by both different parts of the ear and different speeds of vibration

sound location

the process of identifying where a sound came from (humans are able to do this)

olfaction

smell

smell

only sense that does not first go to the THALAMUS

olfactory bulb

smell is processed here first:

pheromones

chemical, produced by a person that are designed to stimulate behavior in another person

smell, taste

chemical sense

gustation

taste

tongue, mouth, brain

areas that work on taste:

sweet, sour, salty, bitter, umami, olegustus

types of taste

taste receptors

number of _______ determine your ability to taste

supertaster, medium taste, non taster

types of taster

pain

a sensation produced in the brain, usually but not always produced by a physiological event in your body

separate cells

to detect hot and cold

phantom limb pain

amputees experiencing pain in the missing limb

Gate theory of pain

“gates” in your spinal chord which “open and close” to control pain

vestibular

balance

semi circular

_____ in brain control balance:

kinesthesis

movement

kinesthesis

allows you to move WITHOUT needing to focus on the individual body parts

neurons

the nervous system is made up of:

glial cells

neurons are protected and nourished by:

glial cells

build myelin

myelin

increase the speed of processing

glial cells

send signals through synapses through the use of neurotransmitters

synapses

the gaps between neurons

interneurons

connect different parts of the brain and the spinal chord, main type of neuron

peripheral

nervous system which includes sensory neurons

sensory neurons

afferent nerve fibers that take input from sensory receptors and send it the brain or spinal chord

spinal chord

most signals are sent to the brain, but they may be processed by the ______ if a quick, reflective response is needed

reflex arc

signals being sent to the spinal chord for a quick response, usually used for pain signals

motor neurons

(efferent nerve fibers) send signals in the opposite direction, from the CENTRAL nervous system TO muscles and organs

excitatory neurotransmitters

when these chemicals are released from the terminal buttons, they excite connecting neurons and cause them to fire

inhibitory neurotransmitters

these inhibit the next neurons from firing

resting potential

the neuron is inactive and has a negative charge

depolarization

occurs when a signal is sent, this is when the channels in a neuron open, allowing ions to enter the cell and giving it a brief POSITIVE charge

all or nothing principle

the idea that during depolarization, if the charge is not strong enough the cell will not fire (release neurotransmitters)

threshold

minimum strength a signal needs to reach

action potential

an electrical impulse caused by reaching the threshold

refractory period

after the action potential impulse, a period when the cell CANNOT fire again as it RESETS

reuptake

part of the refractory period in which neurotransmitters are reabsorbed by the synapse, (could also be destroyed)

glutamate

an excitatory neuron which assists with normal brain operations, thinking, memory, and long term potentiation

GABA

an inhibitory neurotransmitter which calms the CNS

myasthenia gravis

an autoimmune neuromuscular disorder that causes weakness and fatigued muscles by reducing ACh receptors

multiple sclerosis

condition that causes the immune system to damage the myelin sheath and underlying nerve fibers, leading to a wide range of neurological symptoms

seretonin

neurotransmitter that controls mood, emotion, appetite, and sleep

dopamine

neurotransmitter than controls pleasure, rewards, and motivation

substance P

neurotransmitter than controls pain perception and pain communication

norepinephrine

neurotransmitter than controls alertness, fight flight or freeze response, and fear development

endorphins

relieve pain/stress and are released by the pituitary gland