Chapter 2 - Brain Flashcards
Neuron
A nerve cell; the basic building block of the nervous system.
Biological Psychology
A branch of psychology concerned with the links between biology and behavior.
Dendrite
The bushy, branching extensions of a neuron that receive messages and conduct impulses toward the cell body.
Axon
The extension of a neuron, ending in branching terminal fibers through which messages pass to other neurons or to the muscles / glands.
Myelin Sheath
A layer of fatty tissue segmentally encasing the fibers of many neurons, enables vastly greater transmission speed of neural impulses as the impulse hops from one node to the next.
Action Potential
A neural impulse* - a brief electrical charge that travels down the axon. Generates by the movement of the positively charged atoms in and out of channels in the axons membrane.
Threshold
The level stimulation required to trigger a neural impulse.
Synapse
The junction between the axon tip of sending neuron and the dendrite cell body of the receiving neuron.
Neurotransmitters
Chemical messengers that traverse the synaptic gaps between neurons. When released by sending a neuron, neurotransmitters travel across the synapse and bind to receptor sites on the receiving neuron- influencing whether that neuron will generate a neural impulse.
Acetylcholine, Ach
A neurotransmitter that enables learning and memory and also triggers muscle contraction.
Dopamine
Influences movement, learning, attention and emotion.
Not enough: Parkinson’s
Too much: Schizophrenia
Serotonin
Affects mood, hunger, sleep, and arousal.
Not enough: Depression
Endorphins
“Morphine within” - natural, opiate like neurotransmitters linked to pain control and to pleasure.
Ex: Runner’s high
Nervous System
The body’s speedy, electrochemical communication network, consisting of all the nerve cells of the peripheral and central nervous systems.
Central Nervous System
The brain and the spinal cord.
Peripheral Nervous System
The sensory and motor neurons that connect the central nervous system to the rest of the body.
Nerves
Neural “cables” containing many axons. These bundled axons, which are apart of the peripheral nervous system, connect the central nervous system with muscles, glands, and sense organs.
Sensory Neurons
(Bipolar) Neurons that carry INCOMING information from the sense receptors to the central nervous system.
Motor Neurons
(Multipolar) Neurons that carry OUTGOING information from the central nervous system to the muscles and glands.
Interneurons
(Unipolar) Central nervous system neurons that internally communicate and intervene between the sensory inputs and motor outputs.
Somatic Nervous System
The division of the peripheral nervous system that controls the body’s SKELETAL muscles. Also called the skeletal nervous system.
Autonomic Nervous System
The peripheral nervous system part that controls the glands and the muscles of the INTERNAL ORGANS (such as the heart). It’s sympathetic division arouses, parasympathetic division calms.
Parasympathetic Nervous System
The division of the automatic nervous system that CALMS the body, conserving it’s energy.
Sympathetic Nervous Systems
The division of the autonomic nervous system that AROUSES the body, mobilizing it’s energy in stressful situations.
Reflex
A simple, automatic, inborn response to a sensory stimulus, such as a knee jerk response.
Lesions
Tissue destruction* A brain lesion is a naturally or experimentally caused destruction of brain tissue.
Neural Networks
Interconnected neural cells* - With experience, networks can learn as feedback strengthens or inhibits connections that produce certain results.
Endocrine System
The body’s SLOW chemical communications system; a set of glands that secrete or discharge hormones into the blood stream.
Hormones
Chemical messangers* mostly those manufactured by the endocrine glands that are produced in one tissue and affect another.
Adrenal Glands
A pair of endocrine glands just above the kidneys. The adrenals secrete the hormones
Pituitary Glands
The endocrine systems most influential gland. Under the influence of the hypothalamus, the pituitary regulates growth and controls other endocrine glands.
EEG
Electroencephalogram - and amplified recording of the waves of electrical activity that sweep across the brains surface. *Measures by electrodes placed on scalp.
PET Scan
A visual display of brain activity that detects where a radioactive form of glucose goes while the brain performs a given task.
MRI
A technique that uses magnetic fields and radio waves to produce computer generated images that distinguish among different types of soft tissue; allows us to see structure within the brain.
FMRI
A technique for revealing blood flow and therefore, brain activity by comparing successive MRI scans. MRI stands show brain anatomy - FMRI shows brain function.
Norepinephrine
Helps control alertness and arousal.
Not enough: Depressed mood
