Terms : Hide Images
| 104350691 | neuron | a nerve cell; the basic building block of the nervous system | |
| 104350692 | dendrite | the busy, branching extensions of a neuron that receive messages and conduct impulses toward the cell body | |
| 104350693 | axon | the extension of a neuron, ending in branching terminal fibers, through which messages pass to other neurons or to muscles or glands | |
| 104350694 | 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 | |
| 104350695 | action potential | a neural impulse; a brief electrical charge that travels down an axon. The action potential is generated by the movement of positively charged atoms in and out of channels in the axon's membrane. | |
| 104350696 | synapse | the 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 cleft. | |
| 104350697 | resting potential | the potential difference between the two sides of the membrane of a nerve cell when the cell is not conducting an impulse | |
| 104350698 | refractory period | a resting period after orgasm, during which a man cannot achieve another orgasm | |
| 104350699 | excitatory signals | cause actions; tell body to act quickly | |
| 104350700 | threshold | the level of stimulation required to trigger a neural impulse | |
| 104350701 | all-or-none response | When a muscle fiber contracts,it contracts completely | |
| 104350702 | neurotransmitters | chemical messengers that traverse the synaptic gaps between neurons. WHen released by the sending neuron, neurotransmitters travel across the synapse and bind to the receptor sites on the receiving neuron, thereby influencing whether that neuron will generate a neural impluse | |
| 104350703 | agonists/antagonists | chemical substances that mimic or enhance the effects of a neurotransmitter on the receptor sites of the next cell, increasing or decreasing the activity of that cell | |
| 104350704 | reuptake | process by which neurotransmitters are taken back into the synaptic vesicles | |
| 104350705 | brainstem | the oldest part and central core of the brain, beginning where the spinal cord swells as it enters the skull; the brainstem is responsible for automatic survival functions | |
| 104350706 | medulla | the base of the brainstem; control heartbeat and breathing | |
| 104350707 | reticular formation | the nerve network in the brainstem that plays an important role in controlling arousal | |
| 104350708 | 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 | |
| 104350709 | cerebellum | the ''little brain'' attached to the rear of the brainstem' its functions include processing sensory input and coordination movement output and balance | |
| 104350710 | limbic system | a doughnut-shaped system of neural structures at the border of the brainstem and cerebral hemispheres' associated with emotions such as fear and aggression and drives such as those for food and sex. Includes the hippocampus, amygdala, and hypothalamus | |
| 104350711 | hippocampus | a neural center located in the limbic system that helps process explicit memories for storage | |
| 104350712 | amygdala | two lima-bean sized neural clusters that are components of the limbic system and are linked to emotion | |
| 104350713 | pons | a band of nerve fibers linking the medulla oblongata and the cerebellum with the midbrain | |
| 104350714 | lesion | tissue destruction. A brain lesion is a naturally or experimentally caused destruction of brain tissue | |
| 104350715 | EEG electroencephalogram | an amplified recording of the waves of the electrical activity that sweep across the brain's surface. These waves are measured by electrodes placed on the scalp | |
| 104350716 | CT scan | a series of x-ray photographs taken from different angles and combined by computer into a composite representation of a slice through the body. | |
| 104350717 | PET scan | a visual display of brain activity that detects where a radioactive from of glucose goes while the brain performs a given task | |
| 104350718 | 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 structures within the brains | |
| 104350719 | fMRI | a technique for revealing blood flow and, therefore, brain activity by comparing successive MRI scans. MRI scans show brain anatomy; fMRI sans show brain function | |
| 104350720 | cerebral cortex | the intricate fabric of interconnected neural cells that covers the cerebral hemispheres; the body's ultimate control and information-processing center | |
| 104350721 | frontal lobe | the portion of the cerebral cortex lying just behind the forehead; involved in speaking and muscle movements and in making plans and judgement | |
| 104350722 | parietal lobe | the portion of the cerebral cortex lying at the top of the head and toward the rear; receives sensory input for touch and body position | |
| 104350723 | occipital lobe | the portion of the cerebral cortex lying at the back of the head; included the visual ares. which recieve visual information from the opposite visual field | |
| 104350724 | temporal lobe | the portion of the cerebral cortex lying roughly above the ears; includes the auditory areas, each of which receives auditory information primarily from the opposite ear | |
| 104350725 | hypothalamus | a neural structure lying below 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 | |
| 104350726 | motor cortex | an area at the rear of the frontal lobes that controls voluntary movements | |
| 104350727 | sensory cortex | the area at the front of the parietal lobes that registers and processes body touch and movement sensations | |
| 104350728 | association areas | areas of the cerebral cortex that are not involved in primary motor or sensory functions; rather , they are involved in higher mental functions such as learning, remembering, thinking and speaking | |
| 104350729 | aphasia | impairment of language, usually caused by left hemisphere damage either to Broca's area (impairing speaking) or to Wernicke's area (impaired understanding) | |
| 104350730 | Broca's Area | controls language expression- an area of the frontal lobe, usually in the left hemisphere, that directs the muscle movements involved in speech | |
| 104350731 | Wernicke's Area | controls language reception- a brain area involved in language comprehension and expression; usually in the left temporal lobe | |
| 104350732 | plasticity | the brain's capacity for modification, as evident in brain reorganization following damage (especially in children) and in experiments on the effects of experience on brain development | |
| 104350733 | glial cells | cells in the nervous system that support, nourish, and protect neurons | |
| 104350734 | corpus callosum | the large band of neural fibers connecting the two brain hemispheres and carrying messages between them | |
| 104350735 | hemispheric specialization | term used to describe the fact the two hemisheres of the brain are designed to handle specific tasks (Left - logic, language; Right - creativity, spatial reasoning, art, emotion) | |
| 104350736 | Nervous System | the body's speedy , electrochemical communication network, consisting of all the nerve cells of the peripheral and central nervous system | |
| 104350737 | Nerves | neural 'cables' containing many axons. These bundled axons, which are part of the peripheral nervous system, connect the central nervous system with muscles, glands, and sense organs | |
| 104350738 | sensory neurons | neurons that carry incoming information from the sense receptors to the central nervous system | |
| 104350739 | interneurons | central nervous system neurons that internally communicate and intervene between the sensory inputs and motor outputs | |
| 104350740 | motor neurons | neurons that carry outgoing information from the central nervous system to the muscles and glands | |
| 104350741 | peripheral nervous system (PNS) | the sensory and motor neurons that connect the central nervous system to the rest of the body | |
| 104350742 | somatic nervous system | the division of the peripheral nervous system that controls the body's skeletal muscles. Also called the skeletal nervous system | |
| 104350743 | autonomic nervous system | the part of the peripheral nervous system that controls the gland and the muscles of the internal organs (such as the heart). Its sympathetic division arouses; its parasympathetic division calms | |
| 104350744 | sympathetic nervous system | the division of the autonomic nervous system that arouses the body, mobilizing its energy in stressful situations | |
| 104350745 | parasympathetic nervous system | the division of the autonomic nervous system that calms the body, conserving its energy | |
| 104350746 | central nervous system (CNS) | the brain and spinal cord | |
| 104350747 | spinal cord | a major part of the central nervous system which conducts sensory and motor nerve impulses to and from the brain | |
| 104350748 | reflexes | a simple, automatic, inborn response to a sensory stimulus, such as the knee-jerk response | |
| 104350749 | neural networks | interconnected neural cells. With experience, networks can learn, as feedbacks strengthens or inhibits connections that produce certain results. COmputer simulations of neural networks who analogous learning |
