Exam #2: Sensations & Learning Theory

What is sensation?

Physical process of stimulation of sensory neurons

What is transduction?

Conversion of physical signals to neural signals.

What is perception?

Psychologically organize and interpret signals, make sense of them

Psychophysics

The study of how physical stimuli are translated into psychological experience.

Data Reduction

Only process small fractions of info/data

Sensory Adaptation

A tendency of sensory receptor cells to become less responsive to a stimulus that isn't new. We are wired to react to new info & ignore the old.

example of sensory adaptation

when you jump into cold water at first you feel freezing, but after a few moments, the water does not feel as cold (sensory receptors are fatigued and do not detect the stimulus as strong as they first did)

Absolute threshold

the minimum stimulation needed to detect a particular stimulus 50 percent of the time

Subliminal perception

the processing of information by sensory systems without conscious awareness

Example of subliminal perception

flash popcorn and coke in movie, not everyone goes out to buy it

What is the corneas function?

Acts as the initial fixed lens - attempts to sharpen and focus (protection).

What is the pupil (iris) function?

regulates the amount of light entering the eye by changing the size of the pupil

What is the function of the lens in the eye?

focus light rays on the retina

What is the function of the retina?

The function of the retina is to translate light into neural impulses for transmission through the optic nerve to the optic centers of the brain.

What are the two type of photoreceptors?

Rods and cones

What is the function of rods in the eye?

Best at detecting movement especially in dark locations. Dominate peripheral but none occur in fovea.

What is the functions of cones in the eyes?

Cones - clarity, color.

In charge for sharper vision, color, high light and densely packed in fovea.

What is the function of photoreceptors?

Convert light into action potentials that allow for the sensation of vision

opponent-process theory

the theory that opposing retinal processes (red-green, yellow-blue, white-black) enable color vision. For example, some cells are stimulated by green and inhibited by red; others are stimulated by red and inhibited by green

Dark -> light adaptation

Our pupils constrict and rods "shut down" quickly

Light -> dark adaptation

Our pupils dilate slowly and rods build up slowly. Take up to 30 minutes for eyes to adjust.

Bipolar cells

In the retina, the specialized neurons that connect the rods and cones with the ganglion cells.

Optic nerve

the nerve that carries neural impulses from the eye to the brain

Optic chiasm

point at which optic nerve fibers cross in the brain

Occipital cortex

Brain region that processes visual information.

color vision

Integration of information from red, green, and blue cones

Young-Helmholtz trichromatic theory

the theory that the retina contains three different color receptors—one most sensitive to red, one to green, one to blue—which, when stimulated in combination, can produce the perception of any color.

Visual pathways in the brain

Nerve impulses travel from each eye along the optic nerves and meet at the optic chiasm

Here, half of the nerves from each side cross and resume to the back of the brain

The left side of the brain receives half of the left optic nerve and half of the right optic nerve

The same goes for the right side

The binocular field of vision is where left and right fields of vision overlap.

Ventral streams

-used in neurological labelling for visual functioning

- important part of visual processing & perception

-what things are- object recognition. Where stream

Dorsal streams

- Where and how of our orientation

- Parietal lobe (orientation)

- Location & movement of object, how to locate, avoid

Perceptual Organization (Gestalt)

Separate figure from ground; identifying what is the main figure and what is the background (less focus on that)

What are the categories of organizational grouping?

Nearness, similarity, continuity, & closure

Nearness

Close things grouped together

Similarity

Similar things are grouped (purple pixels mold into a t-shirt)

Continuity

we perceive smooth, continuous patterns rather than discontinuous ones

Closure

See complete figures

What are binocular cues of depth perception?

retinal disparity and convergence

What are the monocular cues of depth perception?

relative size, interposition, relative clarity, relative height, linear perspective, shadows

Linear perspective

A monocular cue for perceiving depth; the more parallel lines converge, the greater their perceived distance.

Relative size

a monocular cue for perceiving depth; the smaller retinal image is farther away

Relative height

a monocular cue for perceiving depth; objects higher in our field of vision are perceived as farther away

Selective Attention

the ability to focus on only one stimulus from among all sensory input

Perceptual sets

expectations that produce a readiness to process experience in a predetermined way

in-attentional blindness

failing to see visible objects when our attention is directed elsewhere

Change blindness

failing to notice changes in the environment

What percentage of our vision field can you see at a time?

1%

What is the organization of our ear?

Outer ear, ear drum, auditory ossicles, oval window, cochlea, basilar membrane, hair cells

Outer Ear

Funnel auditory energy to ear drum

Ear drum

The part of the ear that vibrates to allow us to hear sound. It is connected to 3 bones

What are the bones in the ear?

hammer, anvil, stirrup

oval window

membrane at the entrance to the cochlea through which the ossicles transmit vibrations

Cochlea

a coiled, bony, fluid-filled tube in the inner ear through which sound waves trigger nerve impulses

Basilar membrane

A structure that runs the length of the cochlea in the inner ear and holds the auditory receptors, called hair cells.

Pitch

a tone's experienced highness or lowness; depends on frequency

Place code

the process by which different frequencies stimulate neural signals at specific places along the basilar membrane, from which the brain determines pitch

Temporal code

the cochlea registers low frequencies via the firing rate of action potentials entering the auditory nerve

What happens in the ear when you hear high pitch?

The waves crash early in the cochlea

What happens in the ear when you hear low pitch noise?

The waves are longer, crash later

What impacts pitch?

frequency

Conductive hearing loss

hearing impairment caused by interference with sound or vibratory energy in the external canal, middle ear, or ossicles

Hunters notch

When hair cells are damaged in the area affected by gunfire's pitch. Wears out basilar nerve at that pitch but other pitches can be heard fine

Sensorineural deafness

Signal not getting from cochlea to brain (born deaf, damage to signal connection)

Cochlear implants

a device for converting sounds into electrical signals and stimulating the auditory nerve through electrodes threaded into the cochlea

Perception is a ----- task

learned

3 different sets of nerves in charge of touch:

texture, patterns, pressure

Thermoreceptors

respond to changes in temperature (shivering)

What part of our body has the most nerve endings?

Face & hands

Pain in body

It has a separate set of neurons that has diverse amounts of triggers and receptors.

Phantom limb

perceived sensation, following amputation of a limb, that the limb still exists

Referred pain

pain that is felt in a location other than where the pain originates

Opiates

opium and its derivatives, such as morphine and heroin; depress neural activity, temporarily lessening pain and anxiety (block signals)

Gate Theory

the suggestion that only a certain amount of information can be processed by the nervous system at a given time. Either pain OR other feelings -distraction

How many tastes do we have

4-6

Supertasters

people with heightened sensitivity to all tastes and mouth sensations

Learning

Enduring changes in behavior due to experience

Behaviorism

the science of behavior that focuses on observable behavior only

Watson & Skinner

redefined psychology as "the scientific study of observable behavior". They further suggested that behavior is influenced by learned associations, through a process called conditioning.

Conditioning

the process of learning associations

Classical conditioing

Associating 2 stimuli

operant conditioning

Associating responses & consequences

What is unconditioned stimulus?

something that reliably produces a naturally occurring reaction in an organism

What is conditioned stimulus?

a previously neutral stimulus that, after becoming associated with the unconditioned stimulus, eventually comes to trigger a conditioned response

Unconditioned response

an unlearned, naturally occurring response to an unconditioned stimulus

Conditioned response

a learned response to a previously neutral stimulus

examples of unconditioned stimulus

food, loud noise, light in eye, puff of air in eye

examples of conditioned stimulus

Presenting the bell along with the food

example of unconditioned response

salivation

example of conditioned response

salivation to bell

Examples of classical conditioning

Pavlov's dogs, Little Albert, Aversions, phobias

acquisition

The initial stage in classical conditioning; the phase associating a neutral stimulus with an unconditioned stimulus so that the neutral stimulus comes to elicit a conditioned response. In operant conditioning, the strengthening of a reinforced response.

stimulus generalization

the tendency to respond to a stimulus that is only similar to the original conditioned stimulus with the conditioned response (fluffy white anything -> white bunny)

Stimulus discrimination

the ability to differentiate between a conditioned stimulus and other stimuli sufficiently different from it

Extinction (operant conditioning)

A process by which a response that has been learned is weakened by the absence or removal of reinforcement.

Spontaneous activity

behavior that is simply emitted by an organism rather than being elicited by external stimulation.

Examples of Classical conditioning discrimination

A kid can tell the difference between lost favorite teddy bear and replacement

Aversive conditioning

a type of counterconditioning that associates an unpleasant state (such as nausea) with an unwanted behavior (such as drinking alcohol)

Counter conditioning

a classical conditioning procedure for changing the relationship between a conditioned stimulus and its conditioned response

Operant conditioning

Learning based on the consequences of responding.

Types of consequences in operant conditioning

Positive and negative

Positive consequences

Something is added after behavior