Chapter 2: The Brain And Behavior Flashcards
Nervous system
The body’s electrochemical communication circuitry
Plasticity
The brain’s special capacity for change
Afferent nerves
Also called sensory nerves; nerves that carry information about the external environment to the brain and spinal cord via sensory receptors
Efferent nerves
Also called motor nerves; nerves that carry information out of the brain and spinal cord to other area of the body
Neural networks
Networks of nerve cells that sensory input and motor output
Central nervous system (CNS)
The brain and spinal cord
Peripheral nervous system (PNS)
The network of nerves that connects the brain and spinal cord to other parts of the body
Somatic nervous system
The body system consisting of sensory nerves, whose function is to convey information from the skin and muscles to the central nervous system about conditions such as pain and temperature, and the motor nerves, whose function is to tell muscles what to do
Autonomic nervous system
The body system that takes messages to and from the body’s internal organs, monitoring such processes as breathing, heart rate and digestion
Sympathetic nervous system
The part of the autonomic nervous system that arouses the body to mobilize it for action and thus is involved in the experience of stress
Parasympathetic nervous system
The part of the nervous system that calms the body
Stress
The responses of individuals to environmental stressors
Stressors
Circumstances and events that threaten individuals and tax their coping abilities and that cause physiological changes to ready the body to handle the assault of stress
Neurons
One of two types of cells in the nervous system; neurons are the nerve cells that handle the information processing function
Glial cells
The second of two types of cells in the nervous system; glial cells (also called glia) provide support, nutritional benefits, and other function to keep neurons running smoothly
Cell body
The part of the neuron that contains the nucleus, which directs the manufacturer of substances that the neuron needs for growth and maintenance
Dendrites
Treelike fibers projecting from a neuron which receive information and orient it toward the neuron’s cell body
Axon
The part of the neuron that information away from the cell body and toward other cells
Myelin sheath
A layer of fat cells that encases and insulates most axons
Resting potential
The stable, negative charge of and inactive neuron between -60 and -75 millivolts
Action potential
The brief wave of posative electrical charge that sweeps down the axon
All-or-nothing principle
The principle that once the electrical impulse reaches a certain level of intensity (its threshold), it fires and moves all the way down the axon without losing any intensity
Synapses
Tiny spaces between neurons; the gaps between neurons are referred to as synaptic gaps
Neurotransmitters
Chemical substances that are stored in very tiny sacs within the neuron’s terminal buttons and involved in transmitting information across a synaptic gap to the next neuron
Acetylcholine (ACH)
Usually stimulates the firing of neurons and is involved in the action of muscles, learning, and memory. People with Alzheimer’s often have and ACH deficiency
GABA (gamma-aminobutyric-acid)
Neurotransmitters in nearly one third of all the brain’s synapses; helps keep many neurons from firing and controls the precision of which neurotransmitters are being carried from one neurons to the next. Low levels of GABA are linked to anxiety and is often included in anti anxiety medication
Glutamate
Has a key role in exciting many neurons to fire and is especially involved in learning and memory; too much glutamate can cause headaches and seizures; glutamate is a factor in anxiety, depression, schizophrenia, Alzheimer’s, and Parkinson’s disease
Norepinephrine
Inhibits the firing of neurons in the central nervous system, but excited the heart muscle, intestines and urogenital tract; stress stimulates the release of norepinephrine; this NT helps to control alertness
Dopamine
Helps to control voluntary movement and affects mood, sleep, attention, learning, and the ability to recognize rewards and other important signals in the environment. Low levels are linked to Parkinson’s disease, high levels to extroversion, and extreme high levels to schizophrenia.
Serotonin
Involved in the regulation of sleep, mood, attention and learning. It teams with norepinephrine and acetylcholine to regulate states of sleep and wakefulness; this NT is key to maintaining the brain’s neuroplasticity; low levels are linked to depression, and many drugs for depression treatment contain serotonin
Endorphins
Naturally opiates that mainly stimulate the firing of neurons. Endorphins shield the body from pain and elevate feelings of pleasure. A long distance runner, a woman giving birth, and a person in shock after a car wreck would all have elevated levels of endorphins. Narcotics such as morphine mimic the effect of natural endorphins by stimulating the same receptors in the brain
Oxytocin
A hormone and neurotransmitter that plays an important role in the experience of love and social bonding. Oxytocin is released in women after giving birth and in both genders after orgasm.
Agonist
A drug that mimics or increases a neurotransmitters effects
Antagonist
A drug that block’s a neurotransmitters effects
Hindbrain
Located at the skull’s rear, the lowest portion of the brain, consisting of the medulla, cerebellum, and pons
Cerebral cortex
The thin outer layer of the cerebellum that is involved in higher brain functions such as thinking, learning, problem solving, language and social behavior
Cerebellum
Central to motor coordination, particularly balance, postures, and coordinated movements
Thalamus
The relay center of the brain. Sensory information from the receptors in the body travel to the thalamus, which sends it to the appropriate areas of the cerebral cortex
Hypothalamus
The master gland of the limbic system. The hypothalamus plays a role in eating, drinking, and sex as well as emotion, stress, and reward. Maintains homeostasis so it is responsible for the equilibrium of systems such as body temperature and blood pressure.
Reticular formation
A system in the midbrain comprising a diffuse collection of neurons involved in stereotypes patterns such as walking, sleeping and turning to attend to a sudden noise
Brainstem
The stemlike brain area that includes much of the hindbrain(excluding the cerebellum) and the midbrain; connects with the spinal cord at its lower end and then extends upward to encase the reticular formation in the midbrain
Midbrain
Located between the hindbrain and forebrain, an area in which many nerve fiber systems ascend and descend to connect the higher and lower portions of the brain; in particular the midbrain relays information between the brain and the eyes and ears
Forebrain
The brain’s largest division and the most forward part
Limbic system
A set of sub cortical brain structures central to emotion, memory, and reward processing
Amygdala
An almost shaped structure within the base of the temporal lobe that is involved in the discrimination of objects that are necessary for the organisms survival such as appropriate food, mates, and social rivals. Also plays a role in emotional response. Especially in fear and aggression. Detects and stress and is part of the system that triggers fight or flight.
Hippocampus
The structure in the limbic system that has a special role for the storage of memories.
Basal ganglia
Large neuron clusters located above the thalamus and under the cerebral cortex that works with the cerebellum and cerebral cortex to control and coordinate voluntary movements
Occipital lobes
Structures located in the back of the head that respond to visual stimuli
Medulla
Begins where the spinal cord enters the skull. This structure controls many vital functions such as breathing, and heart rate. It also regulates our reflexes
Temporal lobes
Structures in the cerebral cortex that are located just above the ears and are involved in hearing, language processing and memory.
Frontal lobes
Portion of the cerebral cortex behind the forehead, involved in personality, intelligence, and the control of voluntary muscles.
Prefrontal cortex
An important part of the frontal lobes that is involved in higher cognitive functions such as planning, reasoning, and self control
Parietal lobes
Structures at the top and toward the rear of the head that are involved in registered special location, attention, and motor control.
Somatosensory cortex
A region in the cerebral cortex that processes information about body sensations, located at the front of the parietal lobes
Motor cortex
A region in the cerebral cortex, located just behind the frontal lobes, that processes information about voluntary movement
Corpus callosum
The large bundle of axons that connects the brain’s two hemispheres, responsible for relaying information between the two sides
Stem cells
Unique, primitive cells that have the capacity to develop into most types of human cells
Pons
Controls sleep and arousal
