Ch. 2 Flashcards
define biological perspective
concerned with the links between biology and behavior. Includes psychologists working in neuroscience, behavior genetics, and evolutionary psychology
nerve cells ____ ____.
conduct electricity
how do nerve cells “talk” to each other?
by sending chemical messages across a tiny gap that separates them
specific brain systems serve specific _____.
functions
What do phrenology and psychology’s biological perspective have in common?
They share a focus on the links between the brain and behavior. Phrenology faded because it had no scientific basis—skull bumps don’t reveal mental traits and abilities.
what are the names which psychologists who are working on the biological perspective of psychology referred to as?
behavioral neuroscientists neuropsychologists behavior geneticists physiological psychologists biopsychologists
define dendrites
a neuron’s bushy, branching extensions that receive messages and conduct impulses toward the cell body
define axon
the neuron extension that passes messages through its branches to other neurons or to muscles or glands.
how long can axon be?
several feet
define myelin sheath
a fatty tissue layer segmentally encasing the axons of some neurons; enables vastly greater transmission speed as neural impulses hop from one node to the next
define glial cells (glia)
cells in the nervous system that support, nourish, and protect neurons; they may also play a role in learning, thinking, and memory
define action potential
a neural impulse; a brief electrical charge that travels down an axon
define refractory period
(1) a period of inactivity after a neuron has fired. (2) a resting period after orgasm, during which a man cannot achieve another orgasm
define threshold
the level of stimulation required to trigger a neural impulse
define all or none response
a neuron’s reaction of either firing (with a full-strength response) or not firing
When a neuron fires an action potential, the information travels through the axon, the dendrites, and the cell body, but not in that order. Place these three structures in the correct order.
dendrites, cell body, axon
How does our nervous system allow us to experience the difference between a slap and a tap on the back?
Stronger stimuli (the slap) cause more neurons to fire and to fire more frequently than happens with weaker stimuli (the tap)
define neurotransmitters
chemical messengers that cross the synaptic gaps between neurons. When released by the sending neuron, neurotransmitters travel across the synapse and bind to receptor sites on the receiving neuron, thereby influencing whether that neuron will generate a neural impulse
define synapse
he junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron. The tiny gap at this junction is called the synaptic gap or synaptic cleft
define reuptake
a neurotransmitter’s reabsorption by the sending neuron
What happens in the synaptic gap?
Neurons send neurotransmitters (chemical messengers) across this tiny space between one neuron’s terminal branch and the next neuron’s dendrite or cell body.
What is reuptake? What two other things can happen to excess neurotransmitters after a neuron reacts?
Reuptake occurs when excess neurotransmitters are reabsorbed by the sending neuron. (They can also drift away or be broken down by enzymes.)
Serotonin, dopamine, and endorphins are all chemical messengers called ______________.
neurotransmitters
define agonist
a molecule that increases a neurotransmitter’s action
define antagonist
a molecule that inhibits or blocks a neurotransmitter’s action
Curare poisoning paralyzes its victims by blocking ACh receptors involved in muscle movements. Morphine mimics endorphin actions. Which is an agonist, and which is an antagonist?
Morphine is an agonist; curare is an antagonist.
define nervous system
the body’s speedy, electrochemical communication network, consisting of all the nerve cells of the peripheral and central nervous systems
define Central nervous system (CNS)
the brain and spinal cord
define Peripheral nervous system (PNS)
the sensory and motor neurons that connect the central nervous system (CNS) to the rest of the body
define nerves
bundled axons that form neural cables connecting the central nervous system with muscles, glands, and sense organs
define Sensory (afferent) neurons
neurons that carry incoming information from the sensory receptors to the brain and spinal cord
define Motor (efferent) neurons
neurons that carry outgoing information from the brain and spinal cord to the muscles and glands
define interneurons
neurons within the brain and spinal cord; communicate internally and process information between the sensory inputs and motor outputs
define somatic nervous system
the division of the peripheral nervous system that controls the body’s skeletal muscles. Also called the skeletal nervous system
define autonomic nervous system (ANS)
the part of the peripheral nervous system that controls the glands and the muscles of the internal organs (such as the heart). Its sympathetic division arouses; its parasympathetic division calms
define sympathetic nervous system
the division of the autonomic nervous system that arouses the body, mobilizing its energy
define Parasympathetic nervous system
the division of the autonomic nervous system that calms the body, conserving its energy