Sensation and Perception

Sensation: your window to the world

Perception: interpreting what comes in your window 

Transduction

-transforming signals into neural impulses 

-information goes from senses to the thalamus, the to the various areas in the brain

Sensory Adaptation

-decreased responsiveness to stimuli due to constant stimulation 

Cocktail-party Phenomenon

-the cocktail party effect describes the ability to focus ones listening attention on a single talker among a mixture of conversations and background noises, ignoring other conversations.

Energy vs. Chemical senses 

Energy senses: 

Chemical senses: 

Vision

-our most dominating sense

-visual capture

The longer the wave, the more red

The shorter the wavelength the more violent 

PHASE TWO

Phase four: In the brain

-goes to the Visual Cortex located in the Occipital Lobe of the Cerebral Cortex

-feature detectors 

-parallel processing

Trichromatic Theory

Three types of cones:

-Red

-blue

-green

These three types of cones can make millions of combinations of colors

-Does not explain afterimages or colorblindness well

 

Opponent Process Theory

-the sensory receptors come in pairs

'Red/gree

'Yellow/blue

'Black/white

-if the color is stimulated, the other is inhibited

 

Afterimages 

Hearing

Our auditory sense 

We hear sound waves

The height of the wave gives us the amplitude if the sound

-the frequency of the wave gives us the pitch if the sound

Transduction in the ear 

-sound waves hit the eardrum then advil then hammer then stirrup the oval window

-everything is just vibrating

-the COCHLEA is lined with mucus called basilar membrane there are hair cells

-when hair cells vibrate they turn vibrations into neural impulses which are called organ of Corti

-sent up to the thalamus up the auditory nerve

Place Theory

-different hairs vibrate in the cochlea when they different pitches

-so some hairs vibrate when they hear high and other vibrate when they hear low pitches 

 

Deafness

Conduction deafness

-something goes wrong with the sound and the vibration on the way to the cochlea

-you can replace the bones or get a hearing aid to help

Nerve (sensorineural deafness) 

-the hair cells in the cochlea get damaged

-loud noises can cause this type of deafness 

-noway to replace the hairs

-cochlea implant is possible

 ________________________________________________

Sensation

-bottom up processing

Analysis that begins with the sense receptors and works up to the brains integration of sensory information 

-top down processing 

Information processing guided by higher level mental process

As when we construct perceptions drawing on out experience and expectations 

Absolute Threshold

-the minimum stimulation needed to detect a stimulus 50% of the time 

Difference Threshold

-the minimum difference that a person can detect between two stimuli

-also known as just noticeable the 

Webers Law

-the idea that, to perceive a difference between two stimuli, they must differ by a constant percentage not a constant amount

Signal Detection Theory

-predicts how we detect a stimulus amid other stimuli

-assumes that we do not have an absolute threshold

-we detect stuff based on our experiences, motivations and fatigue level

Subliminal Stimulation

-below one's absolute threshold for conscious

Intensity

The amount of energy in a light wave determined by the height of the wave. The higher the wave the more intense the light is

Parallel Processing 

-the processing of several aspects of a problem simultaneously 

color, motion, form

Rods facilitate black and white vision

Cones facilitate color vision 

Frequency 

The number of complete wave lengths that pass throu point at a given time. This determines the pitch of a sound

Short waves= high frequency 

Long waves= low frequency 

Amplitude: is how loud the sound is. The higher the crest of the wave is the louder the sound is. It is measured in decibels

Sensory Interaction: the principle that one sense may influence another

Papillae

-those bumps on our tongue are called Papillae

-papillae help grip food while your teeth are chewing. They also have another special job-they contain your taste buds

-Sweet is sensed when our sensitive taste buds come into contact with sugar , it is found on the tip of your tongue  

-Salty is sensed when our salty taste buds come in contact with salt (sodium chloride)

-Sour is sensed when our sour taste buds come in contact with an acid 

-Bitter is sensed when our bitter taste buds come in contact with our alkaline chemical and it is based on 

-Spicy is sensed when the nocioreseptors in our mouth come into contact with a chemical that irritates them 

_________________________________________________

Touch

-a receptors located in our skin

-gate control theory of pain

-the nervous system blocks or allows pain signals to pass to the brain 

Vestibular Sense

-tells us where our body is orientated in space

-our sense of balance

-located in our semicircular canals in our ears 

Kinesthetic Sense

-tells us where our body parts are

-receptors located in our muscles and joints 

_________________________________________________

Perception 

-the process of organizing and interpreting information, enabling us to recognize meaningful objects and events

Visual Capture

-the tendency for vision to dominate the other senses

Gestalt Psychology 

-gestalt psychology emphasize our tendency to integrate pieces of information into meaningful wholes

Figure Ground Relationship 

-the organization of the visual felid into objects (figures) that stand out from their surroundings (ground)

Grouping

-the perceptual tendency to organize stimuli into groups that we understand 

-PROXIMITY 

we group near by figures together

-SIMILARITY

we group items that are similar together

-CONTINUITY

continuos patterns 

-CONNECTEDNESS

something uniformed and linked together

Depth Perception 

-the ability to see objects in three dimensions although the images that strike the retina are two dimensional

-allows us to judge distance 

 

How do we transfer twi dimensional  objects  to three-dimensional peeception?

-binoculars Cues: depth cues that depend on two eyes 

-monocu

Binocular Cues

-Retinal Disparity: a binocular cue fir seeing depth 

The closer an object comes to you the greater the disparity is between to the two images 

 

Monocular Cues

-interposition: if something is blocking our view we perceive it as closer 

-relative Size: if we know that two objects are similar in size, the one that looks smaller us farther away

-relative Clarity:we assume hazy objects are farther away

-texture gradient:the coarser it looks the closer it is 

-relative height: things higher in our field of vision they look farther away

-relative motion:things that are closer appear to move more quickly 

-liner perspective:parallel lines seem to converge wit distance 

-light snd shadow: dimmer object appear farther away because they reflect less light

Phi Phenomenon 

-an illusion of movement created when two or mire adjacent lights blink on and off in succession 

Perceptual Consistency

-perceiving objects as unchanging even as illumination and retinal images change