Donnelly PSY120--Carol Lecture 3--August 31, 2006 NEUROSCIENCE Neuroscience Understanding the brain & its relation to behavior I. Bio-Psycho-Social model II. Nervous System Electro Chemical Communication System A. Central Nervous System Brain and Spinal Cord 1. Neurons Building blocks (cells) of the nervous system that receive and transmit (send) information. a. Sensory Neurons receive b. Inter Neurons transfer information from one neuron to another c. Motor Neurons transmit (send to react) 2. Neurotransmitters Chemical messengers that relay information from one neuron to the next. a. Dopamine inhibitory effects; linked to Parkinson's disease & schizophrenia. b. Serotonin Linked to sleep, dreaming, arousal, depression, eating disorders, OCD. c. GABA Linked to anxiety d. Acetylcholine Linked to Alzheimer's e. Endorphins Morphine, chemical painkillers. 3. Stages of brain evolution a. Brain Stem Survival (hind brain) i. Oldest and innermost part; central core; (Old Brain) ii. Medulla Controls heart beat, breathing, cross-over point. 1. Influences flow of information between spinal cord & brain. 2. Coordinates swallowing, coughing, sneezing. 3. Regulates blood pressure, breathing, and heartbeat. iii. Cerebellum Muscular control, motor behavior (walking), influences learning & memory. (pons) 1. "little brain" 2. A smaller than normal cerebellum is linked to autism. 3. Damage can produce ataxia (slurred speech, severe tremors, loss of balance)
4. Ataxia is similar to alcohol intoxication (alcohol exerts a strong effect on cerebellum) 5. Pons 6. Connects the 2 halves of the Cerebellum 7. Plays role in integrating movements in left and right side of the body. iv. Thalamus like a telephone switchboard. Orients sensory neurons. v. Reticular Formation Network of neurons that help control arousal and attention. b. Limbic System Emotion, motivation, & memory (mid brain) i. Amygdala Aggression and fear ii. Hypothalamus Hunger & thirst, sex behavior, controls Endocrine system. 1. Sleep 2. Body Temperature 3. Movement 4. Emotional reactions (eg. Damage can uncontrollable cause laughter) 5. A nucleus within hypothalamus is involved in seasonal affect disorder (lack of sun can cause sadness) iii. Nucleus Accumbence Pleasure center c. Cerebral Cortex Information process, foresight (fore brain) i. More than 80% of the brains' weight. ii. 1/8 inch sheet of cells composed of billions of neurons. iii. 100 trillion synaptic connections d. Each part of the brain is built on top of the other part e. The more cortexes an animal has, the more capacity for learning and thinking. Become more adaptable. f. EEG Records brains electrical activity g. CAT Scan X-ray photo reveals brain damage h. PET Scan Activity of different brain areas (e.g. glucose in schizophrenia) i. MRI Picture of soft tissue j. fMRI (functional MRI) - observe both the structures & which structures participate in certain cortical functions B. Peripheral Nervous System network of nerves that link the CNS w/the body
Cerebral Cortex & Information processing I. Frontal Lobe Judgment and planning a. Motor Precise control of fingers, lips, and jaw. b. Pre-motor Speech. Damage will cause problems with speech and writing. c. Pre-frontal Abstract thinking, planning, ability, decision making, and self awareness. II. Parietal Lobe Body sensations a. Pressure, temperature, pain b. Electric stimulation feel warmth, tingling, other sensations in body. c. Damage i. inability to recognize familiar objects by touch ii. Failure to recognize parts of our own body iii. Right-left confusion III. Occipital Lobe Vision a. Responsible for visual perception, recognition, and memory. b. Damage - Inability to recognize familiar objects, visual hallucinations, cortical blindness. c. Left Inability to see more than one thing or one aspect of an object at a time. d. Damage at juncture of occipital, temporal, and parietal lobes would cause inability to recognize familiar faces. IV. Temporal Lobe Hearing. Auditory Cortex a. Damage i. Auditory hallucinations ii. Severe deficits in language comprehension and production. iii. Amnesia b. Electric stimulation Elicit complex (forgotten), vivid memories