Chapter 3 - The Biology Of Behavior - Terms And Concepts pt. 1 Flashcards
Nervous System
A network of specialized cells called neurons and glia that coordinate action and transmit signals between different parts of the body. The nervous system consists of the central nervous system and the peripheral nervous system
Central Nervous System
The part of the nervous system that consists of the brain and the spinal cord
Peripheral Nervous System
Portion of the nervous system that transmits messages to and from the central nervous system that consists of somatic nervous system and the autonomic nervous system
Neuron
Type of cell that is the basic unit of the nervous system (a neuron typically consists of a cell body, dendrites, and an axon Neurons transmit messages to other neurons and to glands and muscles throughout the body)
Glia
Non-neuronal cells that provide support and protection for neurons throughout the nervous system (the name glia comes from the Greek term for glue)
Sensory Neuron
Neuron or nerve cell that carries messages to the CNS from receptors in the skin, ears, nose, eyes, and other receptor organs–also known as afferent neuron.
Motor Neuron
Neuron that transmits messages from the central nervous system to muscles or glands–also known as efferent neuron.
Interneuron
Neuron of the central nervous system that functions as an intermediary between sensory and motor neurons.
Cell Body
The largest part of a neuron, containing the nucleus as well as structures that handle metabolic functions
Dendrites
Branch-like extensions from a neuron with the specialized function of receiving messages from surrounding neurons
Axon
Extension of a neuron that transmits an impulse from the cell body to the terminal buttons on the tip of the axon
Terminal Buttons
Swollen bulb-like structures on the end of a neuron’s axon that releases chemical substances known as neurotransmitters
Resting Potential
State in which a neuron is not transmitting a nerve impulse– a neuron in this state has a net negative charge relative to its outside environment and this state of potential energy prepares it to be activated by a signal from an adjacent neuron
Graded Potential
Voltage change in a neuron’s dendrites that is produced by receiving a signal from another neuron or neurons
Axon Hillock
A specialized region of the cell body near the base of the axon
Action Potential
Electrical signal that flows along the surface of the axon to the terminal buttons, initiating the release of neurotransmitters
All-or-None Law
An action potential will be passed through a neuron’s axon as long as the sum of the graded potentials reaches a threshold. The strength of an action potential does not vary according to the degree of stimulation.
Myelin Sheath
Insulation cover around some axons that increases a neuron’s ability to transmit impulses quickly (myelin sheaths are made of specialized cells called glial cells)
Node of Ranvier
Small gap or exposed neuron between glial cells that for the myelin sheath
Synapse
Includes the synaptic gap and a portion of the presynaptic and postsynaptic membranes that are involved in transmitting a signal between neurons
Neurotransmitter
Chemical substance produced and secreted by neurons that cause a change in the receiving neurons resting potential
Excitatory Postsynaptic Potentials (EPSPs)
Effects that occur when excitatory neurotransmitters cause a depolarizing graded potential to occur on the dendrite or cell body of a receiving neuron making the receiving neuron more likely to fire
Inhibitory Postsynaptic Potentials (IPSPs)
Effects that occur when inhibitory neurotransmitters cause a hyperpolarizing graded postsynaptic potential on a receiving neuron making the receiving neuron less likely to fire
Acetylcholine (ACh)
The neurotransmitter that is released from motor neurons onto muscle fibers to make them contract (also involved in learning memory and cognition)
Noreprinephrine
A major excitatory neurotransmitter in the brain, which is distributed throughout the central and peripheral nervous systems and is important in emotional arousal and stress.
Dopamine
A neurotransmitter involved with the initiation of motor movement, attention, and learning and memory (the dopamine system mediates reward and pleasure and it is the substance of addiction)
Serotonin
A neurotransmitter involved in the control of the sleep/wake cycle, mood and appetite (deficiencies of serotonin are associated with sleep disorders, aggression, and depression)
Gamma-Amino-Butyric-Acid (GABA)
GABA is the major inhibitory neurotransmitter in the brain and spinal cord. It plays an important role in regulating arousal and anxiety.
Endorphins
A class of neurotransmitters substances that function to inhibit the transmission of pain information (morphine and other opiates act by facilitating endorphin transmission)
Glutamate (Glutamic Acid)
An amino acid derived from glucose, which plays an important excitatory function (MSG contains glutamate)
Nerve
A cable-like bundle of myelinated axons that transmits signals from various structures of the body to the spinal cord and the brain.
Somatic Nervous System
Division of the peripheral nervous system that transmits messages to and from major skeletal muscles as well as from sensory organs to the CNS (central nervous system)
Autonomic Nervous System (ANS)
Division of the peripheral nervous system that transmits messages between the central nervous system and the endocrine system as well as the smooth muscles of the heart, lungs, stomach, and other internal organs, which operate without intentional control.
Sympathetic Nervous System
Division of the autonomic nervous system that functions to produce emergency responses such as increased heart rate, pupil dilation, and inhibited digestive activity (the sympathetic nervous system works in tandem with the parasympathetic nervous system)
Parasympathetic Nervous System
Division of the autonomic nervous system that function to conserve energy, returning the body to normal from emergency responses set in motion by the sympathetic nervous system
Cerebral Hemispheres
The two sides (right and left) of the cerebrum
Medulla
Structure low in the brain that controls vital life support functions such as breathing, heartbeat, and blood pressure, as well as many reflexive functions such as coughing and sneezing
Pons
Brain structure located just above the medulla that function in fine-tuning motor messages, programming species typical behaviors, processing sensory information and controlling respiration
Cerebellum
Brain structure located beneath the overhanging back part of the cerebral hemispheres, which function to coordinate and regulate motor movements
Reticular Formation
Set of neural circuits extending from the lower brain up to the thalamus that plays a critical role in controlling arousal and alertness, which is also known as the reticular activating system.
Reticular Activating System (RAS)
Set of neural circuits extending from the lower brain up to the thalamus that plays a critical role in controlling arousal and alertness
Limbic System
Collection of structures located around the central core of the brain that play a critical role in emotional expression as well as motivation, learning, and memory (key structures of the limbic system include the amygdala, the septal area, and parts of the hypothalamus)
Amygdala
A small limbic system structure located next to the hippocampus in the brain that plays an important role in the expression of anger, rage, fear, and aggressive behavior
Hippocampus
Stucture in the brain’s limbic system that seems to play an important role in memory
Septal Area
Structure in the brain’s limbic system that plays a role in the experiencing of pleasure
Meolimbic-Cortical System
The system of dopamine-containing neurons that originate in the ventral pons, project through the nucleus accumbens and septum, and terminate in the frontal cortex, which mediates the reinforcing effects of eating, sex, and addictive drugs
Hypothalamus
Small Structure located below the thalamus in the brain that plays an important role in motivation and emotional expression, as well as controlling the neuroendocrine system and maintaining the body’s homeostasis and is part of the limbic system
Thalamus
Structure located beneath the cerebrum in the brain, which functions as a relay station, routing incoming sensory information to appropriate areas in the cerebral cortex and seems to play a role in regulating sleep cycles
Basal Ganglia
Neural structures involved in the initiation of motor movement and emotion, which includes the caudate nucleus, putamen, and the substantia nigra
