Neurons and Neurotransmitters: Key Structures and Functions in the Nervous System

What part of the neuron receives messages?

Dendrites

What part carries the message away from the cell body?

Axon

What keeps the electrical signal from leaking out?

Myelin sheath

What are the little gaps in the myelin?

Nodes of Ranvier

What does an afferent neuron do?

Carries sensory information IN to the brain/spinal cord

What does an efferent neuron do?

Carries movement instructions OUT to your muscles.

What neurotransmitters are linked to pleasure and pain relief?

Endorphins

Where do neurotransmitters attach to affect the next neuron?

Receptor sites

Which part of the peripheral nervous system is responsible for carrying information to and from the skeletal muscles and is involved in voluntary movement?

Somatic nervous system

Somatic

skeletal muscles = voluntary movement

Autonomic

automatic, things your body does without you controlling them

Which part of the nervous system is responsible for automatic functions such as heart rate and digestion?

Autonomic nervous system

Which brain structure controls basic functions such as breathing, heart rate, swallowing, and digestion?

mendulla

Which part of the brain is most involved in planning ahead, controlling impulses, and thinking about the consequences of your actions?

Prefrontal cortex

The corpus callosum is a thick band of axons that:

Connects the two cerebral hemispheres

A neuron receives an excitatory message. What does this message tell the neuron to do?

Continue sending the message down the axon

Superchiasmatic Nucleus:

a group of brain cells located in the hypothalamus that signal other brain areas when to be aroused and when to shut down.

Stage 1 Sleep

light sleep and is characterized by theta waves breathing and heart rate, slow down feelings of falling or floating.

Stage 2 sleep

characterized by sleep spindles and last appx 20 min, breathing, muscle tension, heart rate and body temp.

Stage 3 sleep

characterized by slow-wave sleep (delta waves) heart rate, respiration, body temperature & difficult to awake.

Body maintenance and restoration & memory

REM sleep

the active state of sleep in which the person's eyes move.

breathing, heart beat, increase in blood flow in genital area.

Body paralysis occurs. REM appears to help us process emotional experiences

REM Behavior disorder:

a condition in which normal muscle paralysis does not occur, leading to violent movements during REM sleep

REM rebound

the loss of REM sleep is reoccupied by spending more time in REM on subsequent

nights.

Sigmund Freud's Interpretation of Dreams

Interpretation of Dreams Dreams are the road to unconscious. Dreams allows us to express fears and sexual and aggressive desires. Manifest Content: what the dreamer recalls on awakening Latent Content: the symbolic meaning of dream

Threat Simulation Theory

suggests an evolutionary function of dreams.

Activation Synthesis Theory

suggests that dreams do not have symbolic meaning but are the

by-product of the brain's random firing of neural impulses during REM sleep.

Night terrors

very frightening non-REM sleep episodes.

Nightmares

a brief scary REM dream that is often remembered

Lysergic Acid Diethylamide

commonly known as dropping acid Main side effects: bizarre hallucinations, distortions in time and body image

Sensation

Receives signals from the environment

Perception

Organizing and interpreting these signals

Receptor transduces energy into a

Neural response

Sensory nerves transfer the coded activity to the central nervous system

Thalamus processes and relays the neural response

Cerebral cortex receives input and process the sensation and perception

Absoutle threshold

the lowest level of stimulation that can be detected 50% of the time

Transducer

turning outside energy into a nerve signal that your brain can understand.

what happens when the sensory organs do not work?, when there is no way for the external energy to be transduced

If the sensory organ can't transduce the information, the brain doesn't receive the sensory signal.

The link between sensation, perception, and our experiences

Directs our sensory systems toward certain stimuli Selects specific information for further processing, Allocates the mental energy needed for that processing, Regulates the flow of resources needed to perform

tasks and coordinate several tasks

AMplitude

loundness or intensity

frequency

encoded as pitch

Auditory pathways

auditory nerve, medulla, mid brain, thalamus, temporal lobe

The gate control theory of pain

When you hurt yourself, pain signals travel from your body → spinal cord → brain.

Smell

Olfactory nerve, olfactory bulb, frontal lobe

Taste

Mouth and tongue, medulla, thalamus, parietal lobe

top down processing

What do I know

Brain knowledge comes DOWN to help you

Bottom up processing

What do I SEE

information comes UP from your senses

Gestalt Principles

Closure, the tendency to complete a figure

Perception is SUBJECTIVE

Fatal familial insomnia

a fatal inherited genetic disorder marked by a buildup of protein in the thalamus, which leads to insomnia, hallucinations, weight loss, dementia and death

Freud believed dreams were the

royal road to the unconscious" & that dreams allowed the

expression of fears, sex, & aggression without censorship

continuity

hypothesis

which

states that dreams

are a way to cope

with daily problems &

issues

memory theory

dreams are

a way to consolidate

information and

weed out the trivial

details as a function

of memory

Activation-synthesis theory

dreams are the result of a highly-aroused brain during

REM & are a random firing of neural impulses.

Dissociation

theory

altered state - the

consciousness

divides into two

different states

that operate

independently.

Prolonged

alcohol use leads

to memory

problems, such

as blackouts &

Korsakoff's

syndrome.

norepinephrine

A neurotransmitter involved in alert and readiness

synapses

tiny gaps between dentrites and axons of different neurons

synapse

where the neurons meet

pavlows

bell= food dog reference