chapt 3 neuro

Nervous system

Nervous system

An electro-chemical system of neurons that carries information to and from all parts of the body

Neuron

The basic cell that makes up the nervous system and that receives and sends messages within that system; basic building block of life

Dendrite

Branchlike structures that receive messages from other neurons

Soma

The cell body of the neuron responsible for maintaining the life of the cell

Axon

Tubelike structure that carries the neural message to other cells

Glial cells

Cells that provide support for the neuron to grow; glue cells

Myelin sheath

Fatty substance that coats the axons of neurons to insulate, protect and speed up the neural impulse

Nerves

Bundles of axons coated in myelin that travel together through the body

Multiple sclerosis

Damage to the myelin sheath leads to a loss of function of damaged cells. What is this known as?

Resting potential

The state of the neuron when not firing but capable of firing.

Action potential

The release of the neural impulse consisting of an electrical charge down the axon.

All or none

Referring to the fact that a neuron either fires completely or does not fire at all

Terminal branches/ axon terminals

At the end of the axon; contain neurotransmitters

Neurotransmitters

Chemical messengers of the nervous system; when released, has an effect on the next cell

Synapse / snynaptic gap

Microscopic fluid-filled space between cells

Excitatory neurotransmitter

neurotransmitter that makes it more likely for a receiving cell to fire

Inhibitory neurotransmitter

neurotransmitter that makes it less likely for receiving cell to fire

Agonist

Chemical substance that mimics or enhances the effects of a neurotransmitter

Antagonist

Chemical substances that block or reduce a cell's response to the actions of a neurotransmitter

Acetylcholine

Neurotransmitter; involved in arousal, attention, memory and controls muscle contraction; Alzheimer's

Serotonin

Neurotransmitter; involved in mood, sleep and appetite; depression

GABA

Neurotransmitter; major inhibitory; involved in sleep and inhibits movement

Glutamate

Neurotransmitter; major excitatory; involved in learning, memory formation and nervous system development

Norepinephrine

Neurotransmitter; like adrenaline; involved in arousal and mood

Dopamine

Neurotransmitter; involved in control of movement and sensation of pleasure; schizophrenia

Endorphins

Neurotransmitter; involved in pain relief

Reuptake

Process by which neurotransmitters are taken back into the sending neuron

Central nervous system

Part of the nervous system consisting of the brain and spinal cord.

Sensory / afferent

A neuron that carries information from the senses to the CNS.

Interneuron

A neuron found in the center of the spinal cord that receives info from the afferent neurons and sends commands to the muscles through the efferent neurons

plasticity

The ability within the brain to constantly change both the structure and function of many cells in response to experience or trauma

Peripheral nervous system

All nerves and neurons that are not contained in the brain and spinal cord but that run through the body itself

Somatic nervous system

Division of the PNS consisting of nerves that carry information from the senses to the CNS and from the CNS to the voluntary muscles of the body

Autonomic nervous system

Division of the PNS consisting of nerves that control all of the involuntary muscles, organs and glands

Motor neurons

Nerves coming from the CNS to the voluntary muscles; efferent neurons

Sympathetic division

Part of the ANS that is responsible for reacting to stressful events and bodily arousal

Parasympathetic division

Part of the ANS that restores the body to normal functioning after arousal and is responsible for the day-to-day functioning of the organs and glands

lesioning

the destruction of brain cells

EEG

Equipment designed to record the brainwave patterns produced by electrical activity of the surface of the brain

CT

Brain imaging method using computer-controlled X-rays of the brain

MRI

Brain-imaging method using radio waves and magnetic fields of the body to produce detailed images of the brain

PET

Brain-imaging method in which a radioactive glucose is injected into the subject and a computer compiles a color-coded image of the activity of the brain with lighter colors indicating more activity

fMRI

Brain-imaging method where a computer tracks changes in the oxygen levels of the blood

Medulla

Brain part responsible for life sustaining functions, like breathing and heart rate

Reticular formation

Brain part responsible for general arousal and alertness

Cerebellum

Brain part responsible for fine motor movement and balance

Limbic system

A group of several brain structures located under the cortex and involved in learning, emotion, memory and motivation. Includes the hippocampus, amygdala and hypothalamus

Thalamus

Brain part responsible for relaying sensory information to the proper sensory cortex; Sensory switchboard

Hypothalamus

Brain part responsible for hunger, thirst, sex drive and sleep. Helps regulate the endocrine system

Hippocampus

Brain part responsible for the formation of new, long-term memories

Amygdala

Brain part responsible for anger and fear responses

Corpus callosum

The band of neurons that connects the right and left cerebral hemispheres

Occipital lobe

part of cerebral cortex responsible for vision

Parietal lobe

part of cerebral cortex responsible for body sensations like touch and temperature sensations

Somatosensory cortex

Area of neurons running down the front of the parietal lobes responsible for processing info from the skin and internal body receptors for touch.

Temporal lobe

part of the cerebral cortex responsible for hearing and meaningful speech

Frontal lobe

part of the cerebral cortex responsible for mental processes, decision making and fluent speech

Motor cortex

Sections of the frontal lobe responsible for sending motor commands to the muscles of the somatic nervous system

Association areas

Areas within each lobe of the cortex responsible for higher mental processing.

Broca's area

part of the frontal lobe that provides the ability to speak clearly

Wernicke's area

part of the temporal lobe responsible for understanding and producing meaningful language

Left Hemisphere

Hemisphere that mostly controls the right hand, spoken language, written language, mathematical calculations, logical thought processes, analysis of detail and reading

Right hemisphere

Hemisphere that mostly controls the left hand, nonverbal skills, visual-spatial perception, musician & artistic processing, emotional thought and recognition, the whole picture, pattern recognition and facial recognition

Endocrine glands

System of glands that secrete chemicals called hormones directly into the bloodstream

Hormones

Chemicals released into the bloodstream by endocrine glands

Pituitary gland

Master gland; secretes human growth hormone & influences other hormone-secreting glands

Adrenal glands

Glands located on top of each kidney that secrete over 30 hormones that deal with stress.