Biological Basis Of Behavior

Psalm 139:13139:13-16 For you created my inmost being; you knit me together in my mother's womb. I praise you because I am fearfully and wonderfully made; your works are wonderful, I know that full well.

Psalm 139:13139:13-16 My frame was not hidden from you when I was made in the secret place. When I was woven together in the depths of the earth, your eyes saw my unformed body. All the days ordained for me were written in your book before one of them came to be.

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Components of a Neuron dendrites nucleus

cell body

terminal branches

axon

myelin sheath

Vocabulary of an Action Potential resting potential: the state of a neuron when not engaged in an action potential (greater positive ions outside the cell membrane and greater negative ions inside the cell)
polarization: inside of neuron is negatively charged relative to the outside


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Vocabulary of an Action Potential neural impulse (action potential): the firing of a nerve cell
threshold of excitation: the level an impulse must exceed to cause a neuron to fire
graded potential: a shift in the electrical charge in a tiny area of a neuron


Synaptic Transmission synapse

terminal button receptor site

synaptic vesicle neurotransmitter

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Neurotransmitters and Their Role acetylcholine (ACh): plays a role in arousal, attention, memory, and motivation
dopamine: plays a role in motor disorders, such as Parkinson’s disease
serotonin: affects emotions, arousal, and sleep


Neurotransmitters and Their Role norepinephrine: influences wakefulness and arousal, as well as learning, memory, and emotional mood
endorphins: reduce pain by inhibiting the neurons that transmit pain messages to the brain


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ervous System Central
ervous System

Brain

Peripheral
ervous System

Spinal Cord

Somatic
ervous System

Autonomic
ervous System

Sensory
eurons

Sympathetic
ervous System

Hindbrain Midbrain Forebrain

Motor
eurons

Parasympathetic
ervous System

Cross--section of the Brain Cross Forebrain Cerebral cortex Thalamus Hypothalamus Midbrain Hindbrain Cerebellum Pons Medulla

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Hindbrain medulla: controls breathing, heart rate, blood pressure
pons: regulation of sleep/wake cycle
cerebellum: involved in balance and coordination of movement


Midbrain The relay point for hearing and vision.
One of the places pain is registered.
brain structures found in midbrain: midbrain: > superior colliculus > inferior colliculus > substantia nigra


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Forebrain Structures thalamus
hypothalamus
cerebral cortex


Forebrain Structures thalamus: sensory switchboard
hypothalamus: governs motivational (hunger, thirst, sex, sleep, temperature control) and emotional responses
limbic system: linked primarily to memory, emotions, drives


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Structures in the Cerebral Cortex frontal lobes
parietal lobes > primary somatosensory cortex > primary motor cortex
temporal lobes
occipital lobes


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Frontal Lobes
voluntary movement

attention
goal goal--directed behavior


Parietal Lobes sensations of touch and bodily position
primary somatosensory cortex: registers and processes body sensations
primary motor cortex: controls voluntary muscle movement


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Temporal Lobe


processes information concerning hearing, smell, and balance and equilibrium

Occipital Lobes


processes information for the sense of vision

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Reticular Formation A network of neurons in the hindbrain, midbrain, and part of the forebrain.
The primary function of this network is to alert and arouse the higher parts of the brain.


Limbic System Diagram

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Limbic System hippocampus: aids in the processing of memory for storage
amygdala: involved in fear and aggression
hypothalamus: bodily maintenance


functions and pleasurable rewards

Left Hemisphere


right hand touch and




speech




language




writing for right handers

movement

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Right Hemisphere





spatial construction






left hand touch and movement

face recognition

nonverbal imagery

writing for left handers

Peripheral Nervous System Somatic

Sensory Neurons

Motor Neurons

Autonomic

Sympathetic

Parasympathetic

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Sympathetic Nervous System







dilates pupils no effect on tear glands weak stimulation of salivary flow accelerates heart, constricts arterioles dilates bronchi inhibits stomach motility & secretions

Parasympathetic Nervous System







constricts pupils stimulates tear glands strong stimulation of salivary flow inhibits heart, dilates arterioles constricts bronchi stimulates stomach motility & secretion

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The Endocrine System Consists of glands: tissues that produce and release hormones
hormones: chemical substances released by glands that helps regulate bodily activities


Endocrine Glands thyroid gland: produces the hormone thyroxin, which regulates the body’s rate of metabolism
parathyroid glands: secrete parathormone, which controls and balances the levels of calcium and phosphate in the blood and tissue fluids


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Endocrine Glands pineal gland: regulates one’s activity level over the course of a day
pituitary gland: produces the largest number of the body’s hormones
posterior pituitary: affects thirst, sexual behavior, and perhaps paternal and maternal behavior


Endocrine Glands anterior pituitary: produces hormones that cause other glands to produce hormones; regulates body growth and also affects motivation and emotion
gonads: the reproductive glands (testes and ovaries)


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Adrenal Glands adrenal cortex: outer covering of the adrenal glands; releases hormones important for dealing with stress
adrenal medulla: inner core of the adrenal glands that also releases hormones to deal with stress


Pancreas An organ lying between the stomach and small intestine.
It secretes insulin and glucagon to regulate bloodblood-sugar levels.


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