Transcript Slide 1
Chapter 6 Neuroscience & Biological Foundations The Nervous System Neurons • Neurons are composed of: – Cell body (soma): directs actions of the cell – Dendrites: extensions that receive information – Axon: extends from cell body, carries electrical potential, sends a chemical message to adjacent neurons via terminal buttons Myelinated Axons Neurons are for Communicating Synapse Neurotransmitters • Serotonin – affects mood, sleep, sensory perception, and other functions, may play a role in psychological disorders like depression • Acetylcholine – involved in memory, muscle action, sleep, emotions, those w/ Alzheimer’s have lower levels • Dopamine – affects movement, attention, memory, learning, plays role in addiction • Norepinephrine – affects learning, memory, emotions, eating, alertness, etc. • Epinephrine – emotions, memory storage… The Nervous System CNS = Central Nervous System PNS = Peripheral Nervous System Peripheral Nervous System PNS includes all nerves outside the brain and spinal cord – Broken down into somatic and autonomic nervous systems… • Somatic NS carries sensory messages to brain and motor commands to the muscles Somatic Nervous System Peripheral Nervous System • Autonomic N.S. regulates automatic body functions (heart rate, breathing) • Sympathetic: “Fight or Flight” • Parasympathetic: Active during digestion Autonomic Nervous System The Spinal Cord Midline Brain View Lower Level Brain Structuresoldest part of the brain 3 major Brain Stem Structures: 1. Pons 2. Medulla 3. Reticular Formation Midline Brain View Corpus Callosum – connects 2 brain hemispheres Thalamus Sensory relay area HypoThalamus 3 F’s… Feeding, Fleeing, Fighting & Sex CereBellum Smoothes movements 4 lobes of the cerebral cortex – Frontal, Parietal, Occipital, Temporal (F-POT) Frontal Lobes: Motor Control, Speech Production, Higher Functions, Personality Broca’s Area Phineas Gage… 1823 - 1861 4 lobes of the cerebral cortex – Frontal, Parietal, Occipital, Temporal (F-POT) Occipital Lobes Summary of Hemispheric Specializations“lateralization” Studying the Brain • Lesion studies: a brain region is destroyed and behavior is observed –Lesions of hypothalamus in animals --> overeating –Strokes interrupt blood flow in brain --> damage brain Studying the Brain • Electrical Recording: overall brain wave activity monitored by electroencephalograph (EEG) • Electrical Stimulation of the Brain (ESB) Studying the Brain • Imaging techniques allow the living brain to be studied for its activity during behavior – CT scans (computed tomography) used to detect brain structure abnormalities in people w/ mental illness meningitis left temporal tumor Studying the Brain –PET scans use radioactive glucose to assess brain activity Control Ecstasy User Studying the Brain MRI Scan of Tumor in Speech Center –MRI scans generate 3D views of the human brain • fMRI – faster version of MRI MRI for Face Recognition in Normal Volunteer >