Psychology Chapter 5 Vocabulary Action potential – an excitation that travels along an axon at a constant strength, no matter how far it must travel Axon – a single, long, thin, straight fiber that transmits information from a neuron to other neurons or to muscle cells Central nervous system – the brain and the spinal cord Cerebellum – a hindbrain structure that is active in the control of movement, especially for complex rapid motor skills and behaviors that require precise timing Cerebral cortex – the outer surface of the forebrain Corpus callosum – a large set of axons connecting the left and right hemispheres of the cerebral cortex and thus enabling the two hemispheres to communicate with each other Dendrite – one of the widely branching structures of a neuron that receive transmissions from other neurons Dopamine – a neurotransmitter that promotes activity levels and facilitates movement EEG – a device that uses electrodes on the scalp to record rapid changes in brain electrical activity Frontal lobe – a portion of each cerebral hemisphere at the anterior pole, with sections that control movement and certain aspects of memory Hemisphere – the left or right half of the brain; each hemisphere is responsible for sensation and motor control on the opposite side of the body Neuron – a cell of the nervous system that receives information and transmits it to other cells by conducting electrochemical impulses Neurotransmitter – a chemical that is stored in the terminal of an axon that, when released, activates receptors of other neurons Occipital lobe – the rear portion of each cerebral hemisphere, critical for vision Parietal lobe – a portion of each cerebral hemisphere; the main receiving area for the sense of touch and for the awareness of one’s own body and perception of location of the body in space Postsynaptic neuron – a neuron on the receiving end of a synapse Resting potential – electrical polarization that ordinarily occurs across the membrane of an axon that is not undergoing an action potential Stem cells – undifferentiated cells Synapse – the specialized junction between one neuron and another’ at this point one neuron releases a neurotransmitter, which either excites of inhibits the next neuron Temporal lobe – a portion of each cerebral hemisphere; the main processing area for hearing, complex aspects of vision, and certain aspects of emotional behavior Thalamus – a forebrain area that relays information to the cerebral cortex Study Questions 1. What are the parts of a neuron? Cell body, dendrites, myelin sheath, axon, terminal branches of axon 3. How does the action potential work? Like a standard light switch with “on” or “off” 5. What does a neuron do at a synapse? Release a chemical that either excites or inhibits the next neutron 9. What hypothesis does the drug L-dopa for Parkinson’s disease support? The link between the transmitter and the disease 10. Why does using Ritalin for ADD muddle the hypothesis that unusual behavior is due to an excess or deficit of synaptic activity? Most people with ADD do not have abnormal dopamine releasers and receptors and many people with abnormal releasers and receptors 11. Why should psychologists care about the brain and effects of brain damage? To distinguish between people who act strangely because of bad experiences and people who have brain disorders, also, studying the brain helps us explain the organization of behavior 13. What happens to people with occipital lobe damage? People with damage here have cortical blindness (no conscious vision, no object recognition, and no visual imagery 14. What is the effect of extensive damage to the parietal region? People can’t decipher where objects are relative to their body, impairs sensation from corresponding part of the body 15. What area is damaged in and what happens in Wernicke’s aphasia? Temporal lobe in the left hemisphere; people have trouble remembering the names of objects and understanding speech, speech is hard to understand, and resort to made up expressions 16. What is the effect of damage to the amygdale? Memory and reaction of emotions is effected and could be lost 17. What is the only sensory information that goes directly to the cerebral cortex? Olfaction (smell) 21. What are the two parts of the autonomic nervous system? Sympathetic nervous system and the parasympathetic nervous system 25. What are some ways the right hemisphere is different from the left hemisphere? Right does not speak, but it understands language especially short words and grammar, does the understanding of emotional content of speech, better for recognizing and understanding facial expressions 27. What is the evidence for the notion that some people are right brained (creative) and left brained (logical)?