EXAM 1 Chapter 2 Definitions -Biological Perspective/Psychology : concerned with the links between biology and behavior. Includes psychologists working in neuroscience, behavior genetics, and Evolutionary psychology. These researchers may call themselves behavioral neuroscientist, neuropsychologist, behavior geneticists, physiological psychologists, or biopsychologists. The study of the cells and organs of the body and the physical and chemical changes involved in behavior and mental processes -Neuron: a nerve cell; the basic building block of the nervous system; the brain is composed of billions of neurons “connected” to each other oDendrites: a neuron’s bushy, branching extensions that receive messages and conduct impulses toward the cell body Constantly receiving input. When threshold exceeds a certain value, neural impulses fires and travels down axon (See Action Potential)
oAxon: the neuron extension that passes messages through its branches to other neurons or to muscles or glands Terminal Branches (of Axon) : form junctions with other cells oMyelin 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
oCell Body: the cell’s life-support center oNeural Impulse: action potential; electrical signal traveling down the axon -Action Potential: a neural impulse; a brief electrical charge that travels down an axon
oAll or none: on or off; not strong or weak (no such thing). It’s there or not. -Threshold: the level of stimulation required to trigger a neural impulse. -Synapse: the junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron; the space between neurons. The tiny gap at this junction is called the synaptic gap or synaptic cleft
-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; the action potentials are propagated by chemicals oEx. serotonin, dopamine, and endorphins -Endorphins: “morphine within”—natural, opiatelike neurotransmitters linked to pain control and to pleasure -Reuptake: a neurotransmitters reabsorption by the sending neuron; synapse is flooded with neurotransmitters, so must be cleared out. The process of reuptake cleans up the synapse by the reabsorption of neurotransmitters and the breaking down of neurotransmitters -Agonist: chemical that mimics neurotransmitter and could fit into the lock; it’s a molecule that excites, it is similar enough in structure to the neurotransmitter molecule that it mimics its effects on the receiving neuron. oEx. morphine mimics the action of endorphins by stimulating receptors in brain areas involved in mood and pain sensations -Antagonists: blocks neurotransmitter; this molecule inhibits. It has a structure similar enough to the neurotransmitter to occupy its receptor site and block its action, but not similar enough to stimulate the receptor; blocks the lock from being used by the neurotransmitter oCurare poisoning paralyzes its victims by blocking Ach receptors involved in muscle movement
oNarcan is also an example of this—antagonist of an endorphin -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 (CNS) : the brain and spinal cord; clusters (networks) working together (neural networks) 40 billion neurons, each with 10k connections=40 trillion synapses oBrain
oSpinal Cord: involved in simple reflexes that bypass brain -Peripheral Nervous System (PNS) : the sensory and motor neurons that connect the central nervous system (CNS) with the rest of the body—controls somatic, automatic, sympathetic, and parasympathetic
-Nerves: bundles axons that form neural “cables” connecting the central nervous system with muscles, glands, and sense organs -Sensory Neurons: neurons that carry incoming information from the sensory receptors to the brain and spinal cord; connect eye and skin to spinal cord -Motor Neurons: neurons that carry outgoing information from the brain and spinal cord to the muscles and glands; much longer axons. Connects spinal cord to muscles inside body. -Interneurons: neurons within the brain and spinal cord that communicate internally and intervene between the sensory inputs and motor outputs; information processing -Somatic Nervous System : the division of the peripheral nervous system that controls the
body skeletal muscles. Also called the skeletal nervous system -Autonomic Nervous System (ANS) : the part of the peripheral nervous system that controls the glands in the muscles of the internal organs (such as the heart). It’s sympathetic division arouses; its parasympathetic division calms -Sympathetic Nervous System : the division of the autonomic nervous system arouses the
body, mobilizing its energy in stressful situations -Parasympathetic Nervous System : the division of the autonomic nervous system that calms the body, conserving it’s energy -Reflex: a simple, automatic response to a sensory stimulus, such as the knee-jerk response -Endocrine System: the body’s “slow” chemical communication system; a set of glands that secrete hormones into the bloodstream
-Hormones: chemical messengers that are manufactured by the endocrine glands, travel through the bloodstream, and affect other tissues
-Adrenal Glands: a pair of endocrine glands that sit just above the kidneys and secrete hormones (epinephrine and norepinephrine) that help arouse the body in times of stress -Lesion: tissue destruction; a brain lesion is a naturally or experimentally caused destruction of brain tissue; can be used for case studies -Electroencephalogram (EEG) : an amplified recording or the waves of electrical activity that sweep across the brain’s surface. These waves are measured by electrodes placed on the scalp; it’s noninvasive; not used for diagnostic purposes—used for research purposes -Positron Emission Tomography (PET/CT) Scan : a visual display of brain activity that detects where a radioactive form of glucose goes while the brain performs a given task; also not commonly used -Magnetic Resonance Imaging (MRI) : a technique that uses magnetic fields and radio waves to produce computer-generated images of soft tissue. MRI scans show brain anatomy; very commonly used for diagnostic purposes, gives very high resolution pictures of whatever it’s scanning -Function MRI (fMRI) : a technique for revealing blood flow and, therefore, brain activity by comparing successive MRI scans; fMRI scans track the images produced in the brain scans of brain tissue to show brain function -Neural Networks: interconnected neurons form networks in the brain; these networks are complex and modify with growth and experience -Brainstem: the oldest part (hindbrain) and central core of the brain, beginning where the
spinal cord swells as it enters the skill; the brainstem is responsible for automatic survival functions -Thalamus: the brain’s sensory switchboard, located on top of the brainstem; it directs messages to the sensory receiving areas in the cortex and transmits replies to the cerebellum and medulla; a sensory “gateway” -Hindbrain
oReticular Formation : a nerve network that travels through the brainstem and plays an important role in controlling arousal (awakeness) oCerebellum: the “little brain” at the rear of the brainstem; functions include processing sensory input and coordinating movement output and balance oMedulla: the base of the brainstem; controls heartbeat and breathing -Midbrain
oLimbic System: neural system (including the hippocampus, amygdala, and hypothalamus) located below the cerebral hemispheres; associated with emotions and drives oAmygdala: two lima-bean-sized neural clusters in the limbic system; linked to emotion oHypothalamus: a neural structure lying below (hypo) the thalamus; it directs several maintenance activities (eating, drinking, body temperature), helps govern the endocrine system via the pituitary gland, and is linked to emotion and
reward oPituitary Glands: the endocrine system’s most influential gland. Under the influence of the hypothalamus, the pituitary regulates the growth and controls other endocrine glands. oHippocampus: critical in new memory formation -Forebrain
oCortex: the middle part of the brain; first couple millimeters of the surface of the
brain. -Glial Cells (glia): cells in the nervous system, nourish, and protect neurons; they may also play a role in learning and thinking -Parts of the Cortex
