chapter 3 lesson1

What is sensation?

the stimulation oof sensory receptors and the transmission of sensory information to central nervous system

What does sensory receptors located?

in sensory organs such as eyes and ears, the skin and elsewhere

how does sensation activate?

stimulations of senses is an automatic process it results from sources of energy like light and sound or from the presence of chemicals as in smell and taste

what is perception?

the process which sensations are organized into an inner representation of the world

how does perception activate

it is not automatic, its an active process i which sensations are organized and interpreted to form an inner representation of the world

what does perception do?

perception begins with sensation but it also reflects our experiences and expectations as it makes sense of sensory stimuli

what is absolute treshold?

The smallest intensity of a stimulus at which we can detect 50% of the time , determine the intensity of the sound auditory can determine if you can hear frequency of sound or the minimal amount of energy that can produce a sensation ‘

ex minimum light to activate visual sensory

what do psychophysicists look for?

they look for the absolute threshold of the senses by exposing individuals to progressively stronger stimuli until they find minimum stimuli that the person can detect 50 percent of the time

More about absolute threshold about how they are different

theses absolute thresholds are not all absolute however some people are more sensitive than others even the same person might have a slightly different response at different times

If your ears were senstive to sound that a lower in pitch

you may hear the collisions amongmolcues

what is psychophysics

Study of relationship between real world and our psychological experiences of them

what does psychophysics do?

Assumes that there are lawful relationships between physical quality of a stimulus (e.g.: weight in ounces) and our subjective evaluation of that stimulus (e.g rating of how heavy the object is

what is pitch

the highness or lowness of a sound as determined by the frequency of the sound waves

if you see light with slightly longer wavelengths

you see infrared light waves , your world would be transformed because head generates infrared light

what is subliminal perceptions

the unconscious processing of sensory information that occurs below the threshold of conscious perception. In other words, it involves the brain detecting and interpreting stimuli that are presented at a level too low for individuals to consciously perceive

what is difference threshold?

Minimal difference needed to detect a change in stimulus quality 50% of the time; also called just noticeable difference (JND).

what is difference of threshold about intensity?

the minimal difference in intensity required between two sources of energy so that they will be perceived as being different

the minimum difference in magnitude of two stimuli required to tell them apart is their what?

difference threshold

what did weber discover

he discovered through lab research that the threshold for perceiving differences in the intensity of the light is just under 2 presence of their intensity

what is Weber's constant or Weber's law

the fraction of the intensity by which a source of physical energy must be increased or decreased so that a difference in intensity will be perceived

what is does the weber law explain

Weber's Law: JND of a stimulus is a constant proportion (Weber fraction) of the original stimulus.

eg.: Weber fraction for weight is 0.05 (2%). A person would notice the difference between a 10

does the webers law apply to eveyone?

Will this apply to everybody anything less than 2 you won't be able to tell Also reduce the wait by 2 half the time can tell , for everybody is his theory sound can play in , light , temp

Comparison to the originally and relation percent

how does sound apply to weber theory?

people are most sensitive to changes in the pitch of founds , tiny as 0.3 percent meaning that on average people can tell when a tone rises or falls in pitch

how does taste apply to webers theory

the sense of tase is much less sensitive . people cannot detect difference in saltiness

what is signal detection theory

the view that perception of sensory stimuli involves interaction of physical, biological and psychological factors such as motivation, alertness, interest, and experience., States that perception is based not only on stimulus intensity.

what does signal detection theory explain?

Can explain why we can sometimes tune things out (e.g., reading a book on a busy subway). If boring book you can listen to noise

Can also explain why we may be especially sensitive to certain stimuli (e.g.: picking out your own name in a room filled with conversation).

why do people not notice?

Not everybody will notice because of the factors gate keeper in you whenever you hear your name works when u are sleeping wakes up for danger responses unconscious monitoring things to wake you up for

Reticular formation doing this

What are the four outcomes of signal detection theory?

Hit, false alarm , miss , correct rejection

what does Hit mean?

there is a signal and the individual correctly says signal present

what does miss mean?

there is a signal but the individual misses it

what does false alarm mean?

there is no signal but the individual mistakenly says there is one

what does correct rejection mean?

there is no signal and the individual correctly says there is no signal

according to signal detection theory?

the relationship between a physical stimulus and a sensory response is not fully mechanical , people ability to detect stimuli depends on their training (learning), motivation (desire) and psychological states such as fatigue or alertness

the intensity of the signal determines what?

it determines whether people will perceive sensory stimuli or difference between signals , another degree to which signal can be distinguished from background sound

its easier to hear a friend in a quiet place then a loud one

one psychologist determined that

in signal detection is focusing in signals you consider important

what is Labelled Lines Hypothesis?

The brain interprets different types of sensory information based on its neural origin and its destination in the brain.

what is feature detectors?

Specialized neurons in the sensory cortex fire in response to specific features of sensory information. such as lines or edges of objects

Neurons in the occipital lobe specializes in?

interpreting information coming from the eyes. They fire in response to colour, textures, movement, or directional lines.

Neurons in the temporal lobes tend to specialize in?

interpreting information coming from the ears. These neurons respond to specific pitch and volume , frequency

What is Sensitization?

the type of sensory adaptation in which we become more sensitive to stimuli that are low in magnitude also called positive adaptation

what is sensory adaption

The process by which organisms respond to the magnitude of incoming stimuli or the process where organisms become more sensitive to stimuli that are low in magnitude and less sensitive to stimuli that are constant or ongoing in magnitude

how does sensitization occur

occurs when we become more sensitive to stimuli of low magnitude. Things get bigger does not mean its good just gets bigger , initial we didn't notice but the more it presence the more we notice

we become less sensitive when

there is constant stimulation

What is desensitization?

the type of sensory adaption in which we become less sensitive to constant stimuli also called negative adaptation

when does desensitization occur?

occurs when we become less sensitive to stimuli that remain unchanged.

We become desensitized to some senses quickly, like smell and touch.

We never really become desensitized to visual or extremely intense stimuli. e.g. odour of ammonia or pain of a bad burn Facilitates learned avoidance and encourages protective self

care when injured.