Chapter Three Brains, Body, & Behavior

The Neuron Building block of nervous system 100 billion neurons (nerve cells) Collect and send information (to and from sensory organs, muscles, glands, and other neurons).

The Neuron -- Structure Dendrite * Receives information Cell Body (soma) * Nucleus, keeps cell alive Axon * Transmits information to another neuron Myelin Sheath * Fatty tissue, insulation, speeds transmission Axon Terminals Nucleus Node of Ranvier

Neuron -- Function Electrical transmission within the cell. Resting potential * Interior of cell has more negative ions Action potential * Electrical charge received; Positive ions rush in and cell becomes temporarily + charged. Message (impulse) is sent within the cell. Neuron (electrical transmission) video

Communication Communication is an electrochemical process. How do messages move through cells? Electrical transmission. How do messages move between cells? Neurochemical transmission Neurotransmitter * Chemical that relays signals across synapse. Glia also communicate, & produce neurotransmitters

SYNAPSE Terminal Button * End of axon; releases chemicals Synapse * Small gap between neurons Neurotransmitter chemicals cross cross this gap Receptor site * Receiving end of dendrite; Neurotransmitters must fit shape of receptor.

Neurotransmitters * Chemical that relays signals across synapse between neurons. Each has a specific shape (structure) and function. Reuptake of unused chemicals. Axon terminal Synapse Dendrite Synaptic Vesicle Neurotransmitter Channel receptor Reuptake pump

Effects of Neurotransmitters Dopamine * Pleasure, learning, emotion, motivation, movement. Disorders: Parkinson’s, Schizophrenia Serotonin * Mood, appetite, sleep, aggression Disorder: Depression Acetylcholine * Muscle contractions, memory, sleep, dreaming Disorder: Alzheimer’s disease

Epinephrine and Norepinephrine* Hormones and neurotransmitters Stress response: fight/flight, learning, memory Physiological and psychological arousal Disorder: depression, ADHD Endorphins * Natural pain reliever Released by exercise Disorder: drug addiction

The Brain The Old Brain: Brain Stem, Cerebellum, Pons, Medulla Image attributed to Stangor, Introduction to Psychology

Brain Stem * Oldest, innermost, basic functions: breathing, attention, motor responses. Medulla * Part of brain stem Controls breathing & heart rate Cerebellum * Behind brain stem Coordinates thinking & voluntary movement Role in emotional responses, learning

Limbic System Hypothalamus * Image attributed to Stangor, 2011, Introduction to psychology Hunger, sex, links nervous system to endocrine system via pituitary gland Hippocampus * Memory VideoVideo Amygdala * Aggression, fear, emotions, stress Connected to sympathetic nervous system

Cerebrum Image attributed to Stangor, Introduction to Psychology Cerebrum * Cerebral cortex and corpus callosum Cerebral Cortex * Outer layer, thinking, language, social skills, consciousness Corpus Callosum * R & L Brain connection & communication Cerebral Hemispheres (in most people) * R = perceptual skills, drawing pictures L = language, math, complex movements Cerebral cortex Corpus callosum Cerebellum Pons Medulla

Frontal Lobes * Thinking, planning, memory, judgment Broca’s area * L frontal lobe; production of language Broca’s aphasia – damage/loss of speech VDOVDO Association Areas * sensory and motor information is combined and associated with stored knowledge. Motor Cortex * Movement; signals to spinal cord & cerebellum Putting the Brain Back Together - Video

Match Brain Structure & Function 1. Cerebellum 2. Hippocampus 3. Motor cortex 4. Medulla 5. Broca’s area 6. Corpus callosum 7. Amygdala 8. Hypothalamus 9. Cerebral cortex A. connects L & R B. speech C. memory D. complex skills E. hunger & sex F. coordination G. aggression & fear H. heart rate I. movement

Plasticity Neuroplasticity * the brain’s ability to change its structure and function in response to experience or damage neurogenesis * the forming of new neurons Plasticity Video

Studying the Brain EEG (Electroencephalograph) CAT/CT (Computerized Axial Tomography) MRI (Magnetic Resonance Imaging) fMRI (functional Magnetic Resonance Imaging) PET (Positron Emission Tomography) PET & MRI Video

Nervous Systems Nerves * Bundles of Interconnected Neurons Fire together/carry messages Image attributed to Stangor, Introduction to Psychology Central Nervous System * Brain and Spinal Cord Interprets, processes and responds to incoming information. Reflex – involuntary response, generally processed through spinal cord

Peripheral Nervous System * Links the CNS to the body’s sense receptors, muscles, and glands Composed of autonomic and somatic nervous system Nervous System Central (Brain & Spinal Cord) Peripheral AutonomicSomatic Sympathetic Parasympathetic

Somatic & Autonomic NS * Somatic * Part of PNS that links CNS and skeletal muscles, skin, and sense organs. Autonomic NS * 2 Parts -Sympathetic & Parasympathetic NS * Sympathetic – activates organs and glands Parasympathetic – calms body, recovery

ENDOCRINE SYSTEM Image attributed to Stangor, Introduction to Psychology Glands that secrete hormones. Hormones * Chemical messengers in the bloodstream. Hormones help regulate emotions and behaviors. Endocrine System Video Endocrine System Video