Chapter 2 Notes-2 PDF

**Plasticity** The brain's ability to change, especially during childhood, by reorganizing after damage or by building new pathways based on experience. **Neuron** A nerve cell; the basic building block of the nervous system. **Cell Body** The part of a neuron that contains the nucleus; the ce...

**Plasticity** The brain's ability to change, especially during childhood, by reorganizing after damage or by building new pathways based on experience. **Neuron** A nerve cell; the basic building block of the nervous system. **Cell Body** The part of a neuron that contains the nucleus; the cell's life-support center. **Dendrites** Neuron extensions that receive and integrate messages and conduct them toward the cell body. **Axon** The neuron extension that sends messages to other neurons or to muscles and glands. **Action Potentials** A nerve impulse; a brief electrical charge that travels down an axon. **Glial Cells** Cells in the nervous system that support, nourish, and protect neurons; they also play a role in learning, thinking, and memory. **Synapses** The junction between the axon tip of a sending neuron and the dendrite or cell body of a receiving neuron. The tiny gap at this junction is called the synaptic gap or synaptic cleft. **Neurotransmitter** Neuron-produced chemicals that cross the synaptic gap to carry messages to other neurons or to muscles and glands. **All-or-None Law** A neuron's reaction of either firing (with a full-strength response) or not firing. **Threshold** The level of stimulation required to trigger a neural impulse. **Refractory Period** In neural processing, a brief resting pause that occurs after a neuron has fired; subsequent action potentials cannot occur until the axon returns to its resting state. **Nervous System** The body's speedy, electrochemical communication network, consisting of all the nerve cells of the central and peripheral nervous systems. **Peripheral Nervous Systems** The sensory and motor neurons connecting the central nervous system to the rest of the body. **Central Nervous Systems** The brain and spinal cord. **The 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. **The Limbic System** Neural system (including the amygdala, hypothalamus, and hippocampus) located below the cerebral hemispheres; associated with emotions and drives. **Frontal Lobes** The portion of the cerebral cortex lying just behind the forehead; involved in speaking and muscle movements and in making plans and judgments. **Parietal Lobes** 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. **Occipital Lobes** The portion of the cerebral cortex lying at the back of the head; includes areas that receive information from the visual fields. **Temporal Lobes** The portion of the cerebral cortex lying roughly above the ears; includes areas that receive information from the ears. **Motor Cortex** The cerebral cortex area at the rear of the frontal lobes; controls voluntary movements. **Somatosensory Cortex** The cerebral cortex area at the front of the parietal lobes; registers and processes body touch and movement sensations. **Association Areas** Cerebral cortex areas involved primarily in higher mental functions, such as learning, remembering, thinking, and speaking **Corpus Callosum** A large band of neural fibers connecting the two brain hemispheres and carrying messages between them. **Neurogenesis** The formation of new neurons. **Consciousness** Our subjective awareness of ourselves and our environment. **Selective Attention** Focusing conscious awareness on a particular stimulus. **Inattentional and Change Blindness** Failing to notice changes in the environment; a form of inattentional blindness.