Brain and Behavior

Neuronal structure Cell body Dendrites Axon Terminal buttons Myelin Vesicles Transporter molecules Myelin

Synapse Synapse - gap between two neurons

Communication within a neuron Action potential Brief electrical charge that travels down an axon as charged ions move in and out of the axon’s membrane

Communication within a neuron Action potentials Threshold of excitation Cell body to terminal buttons All-or-none firing Rate of firing

Communication between neurons Neurotransmitters Chemical messengers released when action potential reaches the terminal button Carry message across the synapse Fit into receptors on the receiving neuron Excitatory Inhibitory

Communication between neurons Synaptic communication is terminated when neurotransmitter is removed from the synapse Reuptake Enzymatic deactivation

Neurotransmitters Acetylcholine Dopamine Norepinephrine Serotonin Glutamate GABA

Drugs All psychotropic drugs work by binding to receptors in the brain Agonists Antagonists

Nervous system Central nervous system - Brain - Spinal cord Peripheral nervous system - All nerves extending from CNS

Nervous system

Autonomic nervous system controls physiological arousal ____________ division (arousing) ___________ division (calming) Pupils dilate EYES Pupils contract Decreases SALIVATION Increases Perspires SKIN Dries Increases RESPIRATION Decreases Accelerates HEART Slows Inhibits DIGESTION Activates Secrete stress hormones ADRENAL GLANDS Decrease secretion of stress hormones

Types of neurons Sensory neurons Motor neurons Interneurons

Reflexes Automatic responses to stimuli Occur entirely within the spinal cord

Brain divisions & regions Brain stem Myelencephalon Medulla Metencephalon Cerebellum Mesencephalon Reticular formation

Brain divisions & regions Diencephalon Thalamus Hypothalamus

Brain divisions & regions Telencephalon Cerebral cortex Complex thought and behavior Limbic system Emotions Basal ganglia Coordination and balance

Cerebral cortex Frontal lobe Temporal lobe Parietal lobe Occipital lobe

Cerebral cortex Frontal lobe Parietal lobe Prefrontal cortex Motor cortex Parietal lobe Sensory cortex

Cerebral cortex Temporal lobe Occipital lobe Auditory cortex Courtesy of V.P. Clark, K. Keill, J. Ma. Maisog, S. Courtney, L.G. Ungerleider, and J.V. Haxby, National Institute of Mental Health Temporal lobe Auditory cortex Occipital lobe Visual cortex

Lateralization of cortical function Left hemisphere Language areas Broca’s area Wernicke’s area Analyzing sequences Right hemisphere Emotion Spatial relations

Corpus Callosum Connects the two cortical hemispheres Corpus Callosum Martin M. Rother Courtesy of Terence Williams, University of Iowa

Split Brain Patients With the corpus callosum severed, objects (apple) presented in the right visual field can be named. Objects (pencil) in the left visual field cannot.

Limbic system Hippocampus Amygdala Hypothalamus Nucleus accumbens

Basal ganglia Coordinates balance and motor output Caudate Putamen Globus pallidus