Biology & Behavior Ch.2.txt

Plato correctly placed mind in the brain. However, his student Aristotle believed that mind was in the heart.Today we believe mind and brain are faces of the same coin. Everything that is psychological is simultaneously biological.

In 1800, Franz Gall suggested that bumps of the skull represented mental abilities. Though incorrect, his theory did successfully establish that different mental abilities were modular.

Specialized cells that conducts impulses through the nervous system - contains three major parts:

Contains nucleus.Carries out metabolic functions of the neuron

Branchlike extensions of the cell body.Receive and send messages from other neurons

Slender, tail-like extension of the neuron.Transmits signal to dendrites or cell body of other neurons, to muscles, glands, and other body parts

Covers the axon of some neurons and helps speed neural impulses

form junctions with other cells

Specialized cells in the brain and spinal cord /Hold neurons together/Removes waste (dead neurons) and does clean-up tasks/Performs manufacturing and nourishing activities

Junction where axon terminal of a sending neuron communicates with a receiving neuron across the synaptic cleft

The slight negative electrical potential of the neuron

Sudden reversal of the resting potential, which initiates the firing of the neuron

Level of depolarization necessary to trigger an action potential/Threshold is all-or-none, like a mousetrap

a junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron. This tiny gap is called the synaptic gap or cleft

A neural impulse. A brief electrical charge that travels down an axon and is generated by the movement of positively charged atoms in and out of channels in the axon�s membrane.

Occurs when positive ions (usually sodium or calcium) enter the neuron, making it more prone to firing an action potential.

Occurs when positive ions (usually potassium) leave the neuron, making it less prone to firing an action potential.

After a neuron fires an action potential it pauses for a short period to recharge itself to fire again. The neuron cannot fire an action potential during this period.

Pump positive ions out from the inside of the neuron, making them ready for another action potential.

When the depolarizing current exceeds the threshold, a neuron will fire. If the depolarizing current fails to exceed the threshold, a neuron will not fire.

the action potential generated is identical

remains the same throughout the length of the axon

Chemical substances released into the synaptic cleft from the axon terminal of a sending neuron/Cross a synapse, /Bind to appropriate receptor sites on dendrites or cell body of a receiving neuron/Influence a cell to either fire or not fire

Protein molecules on surface of dendrites and cell bodies/Have distinctive shapes /Only interact with specific neurotransmitters

Neurotransmitters taken from the synaptic cleft back into the axon terminal for later use/Terminates the excitatory or inhibitory effect on the receiving neuron

Neurotransmitters bind to the receptors of the receiving neuron in a key-lock mechanism

Agonist molecule excites similar to neurotransmitters it mimics its effect on the the receiving neuron

inhibits. to occupy its receptor site and block its action but not similar enough to stimulate the receptor

Causes excitatory effect on skeletal muscle fibers causing them to contract so the body can move

Affects eating, alertness, and sleep

Affects metabolism of glucose and causes stored energy to be released during exercise

Important role in regulating mood, sleep, impulsivity, aggression, and appetite /Primary target of most anti-depressants

Primary excitatory neurotransmitter in the brain

Primary inhibitory neurotransmitter in the brain

Chemicals produced naturally by the brain that reduce pain and the stress of vigorous exercise/Positively affect mood/Literally means �endogenous morphine�/This means we discovered the drug before we understood how it worked

All the body�s nerve cells�an elaborate interwoven network allowing for quick communication.

the brain and spinal cord.

the sensory and motor neurons that connect the central nervous system (CNS) to the rest of the body

Somatic & Autonomic

All sensory nerves /Transmits sense receptor information (eyes, ears, nose, tongue, and skin) to the central nervous system/All motor nerves�voluntary movements/Relays CNS messages to the skeletal muscles of the body

Transmits messages from the brain to the rest of the body/Not under conscious control/Sweating, heartbeat, breathing rate, adrenaline release, etc/Things that are important but that you don�t �decide� to do

Sympathetic & Parasympathetic

�Fight/Flight�/Mobilizes body during stress and emergencies/Prepares body for action

�Rest and digest�/Returns body to normal state after an emergency

Pons/ Medulla/ Cerebellum

Relays messages between cerebellum and motor cortex/Influences sleep and dreaming

Control center for heartbeat, breathing, blood pressure, swallowing, and coughing/Reticular Formation/Arousal system and activates cerebral cortex

Coordinates skilled movement/Regulates muscle tone and posture/Role in motor learning and probably cognition

Medulla & Reticular Formation & Thalamus

is the base of the brainstem that controls heartbeat and breathing.

is a nerve network in the brainstem that plays an important role in controlling arousal

is the brain�s sensory switchboard, located on top of the brainstem. It directs messages to the sensory areas in the cortex and transmits replies to the cerebellum and medulla

the "little brain" attached to the rear of the brainstem. it helpd coordinate voluntary movements and balance

Thalamus, Limbic System, Corpus callosum

Relay station between cerebral cortex and lower brain centers

Group of structures involved in emotional expression, memory, and motivation

Band of nerve fibers that connects the two sides of the brain

is a doughnut-shaped system of neural structures at the border of the brainstem and cerebrum, associated with emotions such as fear, aggression and drives for food and sex. It includes the hippocampus, amygdala, and hypothalamus

Acts as relay station for information in and out of forebrain

Controls hunger, thirst, and body temperature; involved in emotions; helps control the endocrine system

A role in emotional responses to unpleasant or punishing stimuli

Memory storage, navigation, and response to new or unexpected stimuli

A system of ductless glands that manufacture hormones and secrete them into the blood stream to affect other parts of the body

Chemical made and secreted in one part and affects another part of the body.

Controls growth hormone and activates other endocrine glands

Secretes hormone that controls sleep/wakefulness cycle

Cerebral hemispheres & Corpus callosum & Cerebral cortex

The right and left halves of the cerebrum; they control movement and feeling on the opposite side of the body

The thick band of nerve fibers that connects the two cerebral hemispheres and makes possible the transfer of information and synchronizes activity between the hemispheres

The gray, convoluted covering of the cerebral hemispheres that is responsible for the higher mental processes of language, memory, and thinking.

Areas of the cerebral cortex that house memories and are involved in thought, perception, and language

Laterlization, Left hemisphere, & right hemisphere

Functional specialization of one of the cerebral hemispheres

Controls: Right side of body /Most functions of speech and written language/Coordinates complex movements

Controls left side of body/Specialized for:Visual-spatial perception/Interpreting nonverbal behavior/Right hemisphere damage can cause:/Attentional deficits/Inability to view objects in the left visual field

controls left side of the body/music processing /emotional thinking /perceiving spatial relations

Control right side of boy /spoken and written language /numerical skills /reasoning (logic)

Rare surgical treatment for severe epilepsy/Corpus callosum is cut, separating the two hemispheres/Each half has separate sensations, thoughts, and perceptions/When picture is shown to the right eye:/Left hemisphere verbally reports what is seen/When picture is shown to the left eye:/Right hemisphere remembers what is seen but can not verbally report it/Can pick out the shown item by touch with left hand/Increased knowledge about lateralization

Extend from front of brain to skull�s top center/Largest of brain lobes/Contain motor cortex, Broca�s area, & frontal association areas

Rear of frontal lobes/Controls voluntary body movement/Participates in learning and cognitive events

Control�s production of speech sounds

Physical inability to create speech or speech sounds/Caused by damage to Broca�s area

Thinking, motivation, planning, impulse control, emotional responses

Somatosensory cortex/Body awareness and spatial orientation/Somatosensory cortex /Touch, pressure, temperature, and pain register

Front of parietal lobes/Touch, pressure, temperature, and pain register�Wired� to opposite sides of body Affected by experience

The lobes that are involved in the reception and interpretation of visual information; they contain the primary visual cortex

The area at the rear of the occipital lobes where vision registers in the cerebral cortex

Involved in the reception and interpretation of auditory information

The part of each temporal lobe where hearing registers in the cerebral cortex

Language area of the left temporal cortex/Comprehends spoken word, formulates coherent speech, and written language

Asphasia caused by damage to Wernicke�s area. /Speech is fluent and clearly articulated but doesn�t make sense to listeners

Areas that interpret auditory stimuli

Dendrites and axons grow as synapses develop/Pruning/The process through which the developing brain eliminates unnecessary or redundant synapses

Development of myelin sheaths around axons

Some occurs early in life/Spatial perception occurs around age 8 or so

Brain�s ability to reorganize or reshape in response to internal and external sources/Brain gains and loses synapses throughout life

May explain superior ability to perceive emotions

May explain superior ability in spatial tasks

Women use right parietal cortex and right frontal cortex/Men use left hippocampus/Both use different areas to process location of sound/More studies are needed to look for links between brain differences and actual behaviors.

Records electrical brain wave activity

Cross-sectional x-ray images

High resolution images w/o x-rays

Reveals precise brain structure and activity

uses magnetic fields and radio waves to produce computer-generated images that distinguish among different types of brain tissue.

determines active brain regions by measuring heightened blood flow. Here, subject is lying about what cards they have

Reveals brain activity based on blood flow, oxygen use, and glucose consumption

Measures magnetic changes in brain when neurons fire

Measure magnetic changes showing neural activity within the brain as rapidly as it occurs

one dominant gene or two recessive genes required for a trait to be expressed

inheritance pattern in which a trait is influenced by both genes and environmental factors

many genes influence a particular characteristic like skin color

involves genes on the X and Y chromosomes e.g., male or female body type or red-green color blindness

field of research that uses twin and adoption studies to investigate the relative effects of heredity and environment on behavior