Psych (Conciseness and Perception)

Sensation

The detection of physical stimuli and transmission of that information to the brain.

Can be light or sounds waves, molecules of food or odor, or temp. and pressure changes.

Perception

The brains further processing, organization, and interpretation of sensory information.

The 4 stages

Stimulus

Sensation

Sensory Coding

Perception

Bottom-up processing

Based on physical features of the stimulus.

Top-down processing

How knowledge, expectations, or past experiences shape the interpretation of sensory information. Content affects perception.

Transduction

The translation of stimuli.

Sensory systems translate the physical properties of stimuli into patterns of neural impulses.

Primary sensory areas

Regions in the brain where information about vision, hearing, taste, smell, and touch are projected.

Qualitative

consists of the most basic qualities of a stimulus.

Ex:the difference between a tuba’’s honk and a flute’s toot. Or the difference between a salty taste and a sweet one.

Quantitative

consists of the degree or magnitude of those qualities.

Ex: Loudness of the honk, the softness of the toot, the relative saltiness or sweetness. Brightness of light.

Absolute Threshold

the minimum intensity of stimulation that must occur before you experience a sensation.

(the stimulus intensity you would detect 50 percent oof the time)

Difference Threshold

Sometimes called the Just Noticeable Difference. The smallest difference between two stimuli that you can notice.

Signal Detection Theory

Detecting a stimulus is not an objective process. It’s a subjective decision with two components:

1) sensitivity to the stimulus in the presence of noise

2) The criteria used to make the judgement from ambiguous information.

Response Given: Yes

Stimulus Signal: On

(Hit, Miss, False Alarm, Correct rejection)

Hit

Response Given: No

Stimulus Signal: On

(Hit, Miss, False Alarm, Correct rejection)

Miss

Response Given: Yes

Stimulus Signal: Off

(Hit, Miss, False Alarm, Correct rejection)

False Alarm

Response Given: No

Stimulus Signal: Off

(Hit, Miss, False Alarm, Correct rejection)

Correct rejection

Synesthesia

when your brain routes sensory information through multiple unrelated senses, causing you to experience more than one sense simultaneously. Ex: tasting words or linking colors to numbers and letters.

(they experience unique combinations of their different senses, like being able to hear tastes, smell colors, or see sounds.)

Cornea

Light first passes through the cornea, the eye’s thick, transparent outer layer.

Lens

The light is bent further inward and focused to form an image.

Retina

The thin inner surface of the back of the eyeball. Contains the sensory receptors that transduce light into neural signals.

Rods and Cones

The retina has two types of receptor cells: rods and cones

Rods respond at extremely low levels of light and are responsible primarily for night vision. Do not support color vision and they are poor at fine detail

Each retina holds about 120 million rods and 6 million cones.

Cones are less sensitive to low levels of light. They are responsible for vision under brighter conditions and for seeing both color and detail.

Fovea

Center of the retina where the cones are densely packed.

Ganglion cells

The first neurons in the visual pathway with axons. The first neurons to generate actions potentials.

Where Stream (Which lobe)?

Parietal Lobe

What Stream (What lobe)?

Temporal Lobe

Opponent Process

Describes how the brain perceives color and how it can explain afterimages and behavior patterns

Red and green are opponent colors, as are blue and yellow.

different pairs of colors are perceived as opponents due to activity in the ganglion cells.

Fatigue

Staring at one color causes receptor fatigue for that color, and looking elsewhere leads unfatigued receptors for the “opposing” color to produce an afterimage.

Figure of Ground

The ability to visually differentiate between an object and its background

Proximity

The closer two figures are to each other, the more likely we are to group them and see them as part of the same object.

Similarity

We tend to group figures according to how closely they resemble each other, whether in shape, color, or orientation.

Good Continuation

We tend to group edges or contours that are smooth and continuous as opposed to those having abrupt or sharp edges.

Closure

To complete figures that have gaps. The principles of good continuation and closure sometimes can result in seeing contours, shapes, and cues to depth when they do not exist, as is the case with illusory contours.

Common Fate

We tend to see things that move together as belonging to the same group.

Object Constancy

Leads us to perceive the object as unchanging despite changes in sensory data that compose the object.

Face Perception

The visual system is sensitive to faces.

The Thatcher Illusion

Our tendency to process upright faces holistically makes small distortions in any feature obvious. When faces are inverted, this holistic processing is disrupted, and we are less likely to notice changes in the relative orientation os specific features.

Why are faces special?

Recognizing people from facial cues was important as our species evolved, so we developed unique abilities and brain mechanisms that support facial.

The fusiform face area (also known as the fusiform gyrex) is specialized for face perception.

Binocular Depth Cues

Available from both eyes together and are present only when viewing the three dimensional world.

Monocular depth cues

Available from each eye alone and provide organizational information that can be used to infer depth. Motion depth cues emerge when we move through space and depend on relative changes to visual input with motion.

Convergence

when a person views a nearby object, the eye muscles turn the eye inward

Occlusion

A near object occludes (blocks) an object that is farther away.

Relative size

Far-off objects project a smaller retinal image than close objects do, if the far-off and close objects are the same physical size.

Familiar size

Because we know how large familiar objects are, we can tell how far away they are by the size of their retinal images.

Linear perspective

Seemingly parallel lines appear to converge in the distance.

Texture gradient

As a uniformly textured surface recedes, its texture continuously becomes denser.

Position relative to horizon:

All else being equal, objects below the horizon that appear higher in the visual field are perceived as being farther away. Objects above the horizon as being farther away.

Motion Parallax

arises from the relative speed with which objects closer to us changes more quickly than does our view of objects that are farther away, motion provides information about how far away something is.

The Ponzo Illusion

The two horizontal lines appears to be different sizes but are actually the same length.

Binocular Disparity (retinal disparity)

Caused by the distance between humans’ two eyes

Horopter

Imagery circle that passes through the point of focus

Eardrum

A thin membrane that marks the beginning of the ear; sounds waves cause it to vibrate.

Vestibular Senses

Uses information from receptors in the semicircular canals of the inner ear.

Cochlear Implants

Consists of a microphone around the eat and a transmitter fitted to the scalp, link to electrodes that directly stimulate the auditory nerve.

The structures thorough which that information travels through the ears?

Eardrum

Ossicles

Cochlea

Auditory nerve

Cochlear

Hair cells

What are hair cells at the base activated by?

High Frequencysounds

What are hair cells at the tip activated by?

Low Frequency

Place coding

helps us encode sound waves of all frequencies

Vestibular Senses

Perception of balance determined by receptors in the semi-circular canals of the inner war.

Gustation

Sense of taste

Olfaction

Sense of smell

Taste Buds

Taste receptors.

8,000 to 10,000 taste buds.

Olfactory epithelium

A thin layer of tissue within the nasal cavity that contains the receptors of smells.

olfactory bulb

The brain center for smell, located below the frontal lobe.

How is the processing of olfactory information different from the other senses?

Rather than being initially processed by the thalamus (like the signals for all the other senses), smell signals travel directly to the olfactory bulb, located beneath the frontal lobe.

Haptic Sense

The sense of touch

Sensitivity of body parts and cortical tissue

Large amounts of cortical tissue are devoted to sensitive parts of the body like the fingers and lips.

Very little cortical tissue are devoted to other areas like the back of the calves.

FACT: It is possible for some people to be completely insensitive to pain.

FACT: It is possible for some people to be completely insensitive to pain.

Activation-synthesis hypothesis

A hypothesis of dreaming proposing that the brain tries to make sense of random brain activity that occurs during sleep by synthesizing the activity with stored memories.

change blindness

A failure to notice large changes in one's environment.

circadian rhythms

Biological patterns that occur at regular intervals as a function of time of day.

consciousness

One's moment-to-moment subjective experience of the world.

dreams

Products of an altered state of consciousness in which images and fantasies are confused with reality.

Endogenous attention

Attention that is directed voluntarily.

Exogenous attention

Attention that is directed involuntarily by a stimulus.

hypnosis

A social interaction during which a person, responding to suggestions, experiences changes in memory, perception, and/or voluntary action.

insomnia

A disorder characterized by an inability to sleep that causes significant problems in daily living.

meditation

A mental procedure that focuses attention on an external object, an internal event, or a sense of awareness.

Narcolepsy

A sleep disorder in which people experience excessive sleepiness during normal waking hours, sometimes going limp and collapsing.

obstructive sleep apnea

A disorder in which people, while asleep, stop breathing because their throat closes; the condition results in frequent awakenings during the night.

priming

A facilitation in the response to a stimulus due to recent experience with that stimulus or a related stimulus.

REM sleep

The stage of sleep marked by rapid eye movements, paralysis of motor systems, and dreaming.

Subliminal Perception

The processing of information by sensory systems without conscious awareness.

traumatic brain injury (TBI)

Impairments in mental functioning caused by a blow to or very sharp

movement of the head.

Optic Chasm

a crucial structure in the brain's visual pathway where the optic nerves from the two eyes partially cross over

Pineal gland secretes

Melatonin

Rhythm Generator

the brain and body can play a role in cognition, social behavior, and other psychological functions

Weber’s law

The idea is that to notice the change in stimulus it must differ by a constant percentage.

The different pressure in touch or sound.

Heuristics

best guesses based on context and experience

Mental shortcuts that people take to make decisions quickly.

the global workspace model

Posits that conciseness arrises as a function of which brain circuits are active.

Reticular Activating System (RAS)

Responsible for regulating arousal, sleep-wake transitions, and achievement of consciousness.

Gate Control Theory

a theory that explains how non-painful sensations can reduce or override painful sensations