Psych. Unit II

Medulla

-connects brain w/ spinal cord
-controls vital life functions

Brainstem

lowest brain portions include:
-cerebellum
-medulla
-pons
-reticular formation

Subcortex

All brain structures below
cerebral cortex

Facial agnosia

inability to recognize familiar faces

Agnosia

inability to grasp meaning of stimuli
(words, objects, pictures)

Wernicke's area

language comprehension

Broca's area

-language
-grammar & pronunciation

Aphasia

speech disturbance
(result from brain damage)

Association cortex

cerebral cortex areas not primarily sensory/motor fuctions

Motor cortex

control of movement

Frontal lobes

-movement
-smell
-higher mental functions

Temporal lobes

sites where hearing registers in brain

Somatosensory area

Receiving area for bodily sensations

Parietal lobes

bodily sensations register

Occipital lobes

Part of cerebral cortex
-vision registers in brain

Neurological soft signs

subtle brain behavior signs dysfunction
-perceptual & motor problems
-poor hand-eye coordination

"Split-brain" operation

cutting the corpus callosum

Corticalization

Increase in the relative size of cerebral cortex

Cerebral cortex

outer layer of cerebrum

PET scan

'Positron Emission Tomography'
-computer image of brain activity
-brain glucose consumption

fMRI scan

MRI that records brain activity

MRI scan

'Magnetic Resonance Imaging'
-computerized 3D rep. of brain/body based on response 2 magnetic field

Computed Tomographic
CT Scan

computer-enhanced X-RAY image of brain/body

Electroencephalograph
EEG

Device that
-detects
-amplifies
-records
brain elect. activity

Electrical Stimulation of the Brain
ESB

Direct eclect. stimulation & activation of brain tissue

Deep lesioning

Removal of tissue w/n brain using electrode

Electrode

Device 2 elect. stimulate nerve tissue or record activity

Ablation

surgical removal of tissue

Clinical study

detailed single person investigation
(esp. injury/disease)

sensory neuron

info. from senses to CNS

Reflex arc

simplest behavior stimulus provokes auto. response

Spinal Nerves

sensory & motor messages in/out spinal cord

Cranial nerves

leave brain w/o via spinal cord

Limbic system

-forebrain system
-fear & responses

Hippocampus

of limbic system
-storing memories

Hormone

Glandular secretion affects bodily functions or behavior

Growth hormone

Hormone secreted by pituitary gland
-Promotes bodily growth

Pituitary gland

"Master gland"
Hormones influ. other endocrine glands

Pineal gland

-Gland in brain
-regulate body rhythms
& sleep cycles
zzz...

Melatonin

Hormone release by pineal gland in response to daily cycles of
light & dark

Thyroid gland

regulate rate of metabolism

Epinephrine

Adrenal hormone arouse body
-fear
(AKA adrenaline)

Norepinephrine

Adrenal hormone arouse body
-Anger
(AKA noradrenaline)

Adrenal glands

Endocrine glands arouse body
-regulate salt balance
-Adjust body stress
-affect sexual functioning

Handedness

prefer right/left hand in most activities

Dominant hemisphere

side of brain that produces language

Lateralization

Diff. b/w 2 sides of body esp. diff. in brain hemisphere abilities

Hypothalamus

Small brain area
-regulates emo. behavior & motives

Thalamus

relays sensory info. to
cerebral cortex

Reticular Activating System
RAS

of reticular formation
-activates the cerebral cortex

Reticular Formation
RF

network w/n medulla & brainstem
-attention
-alertness
-some reflexes

Cerebellum

controls posture & coordination

Pons

on brainstem
-bridge b/w medulla & other structures

Sensory analysis

Separate sensory info. into important elements

Perceptual features

Basic elements of a stimulus
(e.g. lines, shapes, edges or colors)

Sensory coding

Codes used by sense organs to transmit info. to brain

Sensation

Immediate response in brain caused by sensory organ excitation

Perception

mental process of organizing sensations into meaningful patterns

Psychophysics

study of relationship b/w physical stimuli & sensations evoked in human observer

|Absolute threshold|

minimum amount of physical energy needed to produce a sensation

Difference threshold

change in stimulus intensity that's detectable to an observer

Just Noticeable Difference
JND

Any noticeable difference in a stimulus

Weber's law

JND is a constant proportion of the original stimulus intensity

Perceptual defense

Resistance to perceiving threatening or disturbing stimuli

Subliminal perception

perception of a stimulus below the threshold for conscious recognition

Visible spectrum

part of electromagnetic spectrum to which eyes are sensitive

Retina

light-senstive layer of cells @ back of eye

Accomodation

changes in shape of lens of eye

hyperopia

difficulty focusing nearby objects
farsightedness

Myopia

Difficulty focusing distant objects
nearsightedness

Astigmatism

defects in cornea, lens or eye that cause some areas of vision to be out of focus

Presbyopia

Farsightedness caused by aging

Iris

circular muscle that controls amount of light entering eye
colored part

Pupil

opening @ front of eye through which light passes

Cones

Visual receptors for colors & daylight visual acuity

Rods

Visual receptors for dim light that produce only black & white sensations

Blind spot

An area of the retina lacking visual receptors

Visual acuity

The sharpness of visual perceptions

Fovea

An area @ the center of the retina containing only cones

Peripheral vision

vision @ the edges of the visual field

Trichromatic theory

Theory of color vision based on 3 cone types:
red, green & blue

opponent-process theory

Theory of color vision based on 3 coding systems:
red or green
yellow or blue
black or white

Simultaneous color contrast

changes in perceived hue that occur when a colored stimulus is displayed on backgrounds of various colors

Color blindness

total inability to perceive colors

Dark adaptation

Increased retinal sensitivity to light

Rhodopsin

light-sensitive pigment in the rods

Night blindness

Blindness under conditions of low illumination

Hair cells

receptor cells w/n the cochlea that transduce vibrations into nerve impulses

Organ of Corti

center part of the cochlea, containing hair, cells, canals & membranes

Frequency theory

Holds that tones up to 4,000 hertz are converted to nerve impulses that match the frequency of each tone

Place theory

Higher & lower tones excite specific areas of the cochlea

Conduction deafness

poor transfer of sounds from the eardrum to inner ear

Nerve deafness

Deafness caused by damage to hair cells or auditory nerve

Stimulation deafness

damage caused by exposing the hair cells to excessively loud sounds

Olfaction

sense of smell

Gustation

sense of taste

Anosmia

Loss/impairment of sense of smell

Lock & Key Theory

Odors related to shape of chemical molecules

Pheromone

Airborne chemical signal

Taste bud

receptor organ for taste

Somesthetic sense

sensations produced by
-skin
-muscles
-joints
-viscera
-organs of balance

Skin senses

senses of:
-touch
-pressure
-pain
-heat
-cold

Kinesthetic senses

senses of:
-body movement
-positioning

Vestibular senses

senses of:
-balance
-position in space
-acceleration

Skin receptors

sensory organs for:
-light touch
-pressure
-pain
-cold
-warmth

Visceral pain

Pain originating in internal organs

Referred pain

Pain felt in 1 part of body but comes from another

Somatic pain

Pain from:
-skin
-muscles
-joints
-tendons

warning system

pain based on large nerve fibers;
warns of occurring bodily damage

Reminding system

small nerve fibers pain;
reminds brain body has been injured

Dynamic touch

touch when body in motion
sensation combo. from:
-skin receptors
-muscles
-joints

Sensory conflict theory

Motion sickness result of mismatch b/w info. from:
-vision
-vestibular system
-kinesthesis

Sensory adaptation

decrease in sensory response to an unchanging stimulus

selective attention

voluntarily focusing on a specific sensory input

sensory gating

alteration of sensory messages in spinal cord

gate control theory

pain messages via neural "gates" in spinal cord

beta-endorphin

natural, pain killing brain chemical
(like morphine)

Phantom limb

illusory sensation that a limb stil exists after accidental/amputation loss

Anxiety

apprehension of uneasiness similar to fear but based on unclear threat

control

-where pain is concerned
-ability to regulate the plain stimulus

attention

voluntarily focusing on a specific sensory input

interpretation

-pain concerned
-meaning given to a stimulus

counterirritation

using mild pain to block more intense or long-lasting pain

endocrine system

-glands secretions directly to bloodstream
-lymph system