Body and behavior
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Transcript of Body and behavior
Body and behaviorChapter 6
StandardsStandard II: BiopsychologicalBiological basis of behavior IIA-1.1 Structure and function on neuronIIA- 2.1 Organization of the nervous system
The nervous SystemControls your movement, emotions, thinking, and
behavior (almost all you do)Never at restDivided into 2 parts:Central Nervous System (CNS) – the brain and
spinal cordPeripheral Nervous System (PNS) – nerves
branching beyond the spinal cord
Nervous SystemAll parts are protected:Brain – skull and layers of sheathing (coating)Spinal cord – the vertebrae Peripheral – layers of sheathing - nerves about as thick as a pencilExtremities – nerves get smaller and smaller
NeuronsStrips of long cells that carry messages to and
from the brainCarry messages by chemical-electrical signalsNeuron can “fire” over and over againMessages are sent from neuron to neuronBody contains millions
Parts of a neuron4 Basic Parts:DendritesThe cell body (contains the nucleus)An axonAxon terminals
DendritesShort, thin fibers that protrude from the cell body
Receive impulses (messages) from other neurons and sends them to the cell body
AxonSingle extensionCarries impulses from cell body to the axon
terminalsUsually short, but can be several feet longMyelin sheath (white fatty substance)
insulates and protects the axon; can speed the transmition
Axon TerminalBranch out at the end of the axonRelease neurotransmitters to stimulate
dendrites of the next neuronPositioned opposite of the dendrite of another
neuron
Synapse & NeurotransmittersSynapse – space between the neurons;
transmits messages to the next neuronNeurotransmitters – chemicals released by
neurons - locks or excites receptors Ex: endorphin – inhibits pain norepinephrine – involved with memory and learning
Afferent, Efferent, and InterneuronsAfferent neuron (sensory neurons) – relay
messages from the sense organs (eyes, nose, skin) to the brain
Efferent neuron (motor neurons) – send signals from the brain to the glands and muscles
Interneurons – processes signals only to other neurons
Voluntary vs involuntary activitesSomatic Nervous System (SNS) – the part
of peripheral nervous system that controls voluntary activities (skeletal muscles)
Autonomic Nervous System (ANS) – part of the nervous system that controls involuntary activities
Ex: heartbeat, breathing, digestion, etc.
The brainComposed of 3 parts:HindbrainMidbrainForebrain
HindbrainRear base of the skull; controls basic processes of life
Includes: Cerebellum (behind spinal cord) – controls posture, balance and voluntary movements
Medulla – controls heart rate, breathing, and reflexes
Pons – bridge between spinal cord and brain and produces chemicals needed for sleep
MidbrainSmall, above the ponsIntegrates sensory information and sends it upwards
Medulla and pons extends upward into the midbrain
Reticular Activating System (RAS)- spans across medulla, pons, and midbrain
- Alerts brain of incoming signals and involved in sleep/wake cycle
ForebrainBrains central coreIncludes:Thalamus – integrates sensory information
Hypothalamus – controls hunger, thirst, and changes in temperature
Cerebral Cortex & CerebrumCortex - Outer layer of forebrainCerebrum – inner layerHigher thinking processesGives you ability to learn and store complex and abstract information
Site of conscious thinking processes
Limbic SystemCore of forebrainRegulates our emotions and motivationsIncludes: Hypothalamus, thalamus, hippocampus, and amygdala
Amygdala - controls violent emotions such as rage and fear
Hippocampus: - formation of memories
Lobes of the BrainCerebrum – 2 hemispheresConnected by: Corpus callosumEach hemisphere has deep grooves = regions
or lobesOccipital lobe – visionParietal lobe – body sensationsTemporal lobe – hearing, memory, emotion,
speakingFrontal lobe – organization, planning,
creative thinking
Hemispheres (Left & Right)Corpus callosum – carries messages back
and forth between the 2 hemispheres
Right: Controls left side of body - Nonverbal, spatial, and holisticLeft: Controls right side of body - Verbal, Mathematical, Analytic
Corpus CallosumCan be severed = Split-Brain OperationNow have “2” brains; operate
independently, no communication between the two sides
How Psychologists Study the BrainRecord electrical activity in brain – EEG - wires and electrodes attached to a machine
Stimulation – “make” neurons fire on certain parts of brain and record; determine function
Lesions – cutting or destroying part of brain to see if animal behaves differently
Accidents – learn from brain trauma and tragedies
ImagesCT scans – pinpoint injuries and deterioration
PET scans – capture picture of brain as different parts are being used
MRI – able to see/study activity and structures
- combines benefits of CT and PET scans