Chapter 3 Biological Psychology I Nerve Cells Communication Portals a Neurons the Brains communicators nerve cell specialized for communication i Cell body soma central region manufactures new cell components renewal of cell components ii Dendrites portion of the neuron that receives signals iii Axons and Axon Terminals portion of the neuron that sends signals 1 Synaptic vesicle spherical sac containing neurotransmitters a ii i Glutamate excitatory neurotransmitter in the nervous system relay of sensory information and learning ii GABA Main inhibitory in the nervous system iii Acetylcholine muscle contraction cortical arousal iv Norepinephrine brain arousal v Dopamine Motor function and reward vi Serotonin mood and temp vii Anadamide pain reduction appetite viii Endorphins pain reduction Synapse space between 2 connecting neurons through which messages are transmitted chemically 1 b Neurotransmitters chemical messenger specialized for communication from neuron to neuron Synaptic cleft a gap into which neurotransmitters are released from the axon terminal Glial cells mom cell cell in nervous system that plays a role in the formation of myelin and the blood brain barrier responds to injury removes debris and enhances learning and memory i Astrocytes most abundant glial cells play an important role in embryo development ii Oligodendrocyte promotes new connections among nerve cells and releases chemicals to aid in healing 1 b Electrifying thought i Resting potential electrical charge difference 60 millivolts across the neuronal membrane when the neuron is not being stimulated or inhibited ii Threshold membrane potential necessary to trigger an action potential 1 ii b b II Myelin sheath glial cells wrapped around axons that act as insulators of the neuron s signal Action potential electrical impulse that travels down the axon triggering the release of neurotransmitters Absolute refractory period time during which another action potential is impossible limits maximal firing rates Chemical communication Neurotransmission i Receptor site location that uniquely recognizes a neurotransmitter ii Reuptake means of recycling neurotransmitters Neural Plasticity i Plasticity ability of the nervous system to change ii How the brain changes in development 1 Growth of dendrites and axons 2 Synaptogenesis the formation of new synapses 3 Pruning consisting of the death of certain neurons and the retraction of axons to remove connections that aren t useful 4 myelination the insulation of axons with a myelin sheath ii Neurogenesis creation of new neurons in the adult brain iii Stem cells a cell often originating in embryos having the capacity to differentiate into a more specialized cell The Brain Behavior network a The Central Nervous system brain and spinal cord controls the mind and behavior 1 Cerebral ventricles pockets in the brain that contain cerebrospinal fluid which provide the brain with nutrients and cushion against injury 1 Cerebral Cortex analyzes sensory information helping us to perform complex brain functions including reasoning and language a Forebrain cerebrum forward part of the brain that allows advanced intellectual abilities i Cerebral hemispheres 2 halves of the cerebral cortex 1 1 Corpus callosum large band of fibers connecting the two cerebral hemispheres b Basal ganglia controls movement 1 Frontal lobe preforms excusive functions that coordinate other brain areas motor planning language and memory a Central sulcus groove that separates the frontal lobe b Motor cortex part of frontal lobe responsible for body movement c Prefrontal cortex responsible for thinking planning and language d Broca s area language and speech production 2 Parietal lobe processes touch information integrates vision and touch 3 Temporal Lobe processes auditory information language and autobiographical memory a Auditory cortex devoted to hearing b Wernicke s area involved in understanding speech 2 Occipital Lobe Processes visual Information 3 Cortical Hierarchies a Primary sensory cortex regions of the cerebral cortex that initially processes information from the senses b Association cortex regions of the verbal cortex that integrate simpler functions to perform more complex functions Limbic system 1 Thalamus conveys sensory information to cortex 2 Hypothalamus Oversees endocrine and autonomic nervous system 3 Amygdala regulates arousal and fear 4 Hippocampus processes memory for spatial locations 5 Cingulate cortex emotion formation and processing learning and memory 1 Cerebellum control balance and coordinated movement i Brain Stem i b II Midbrain tracks visual stimuli and reflexes triggered by sounds 2 Pons conveys information to the cortex and cerebellum 3 Medulla regulates breathing and heartbeats 4 Reticular Activating System RAS Triggering arousal Spinal Cord conveys information between the brain and the rest of the body 1 Interneurons send messages to other neurons nearby 2 Reflex automatic motor response to a sensory stimulus The Peripheral Nervous System nerves in the body that extend outside the central nervous system i Somatic nervous system conveys info between the CNS and the body controlling and coordinating voluntary movement ii Autonomic nervous system controls the involuntary actions of our internal organs and glands which participates in emotion regulation 1 Sympathetic nervous system Engaged during a crisis or after actions requiring right or flight 2 Parasympathetic nervous system controls rest and digestion The Endocrine System a network of glands that release hormones into the bloodstream a b IV 1 Pituitary Gland master gland that directs other glands of the body i Oxytocin roles in material and romantic love and trust ii Hormones chemical released into the bloodstream that influences particular organs and glands Adrenal Glands located on top of kidneys that release adrenaline and cortisol during states of emotion arousal i Adrenaline energy boost ii Cortisol regulates blood pressure and cardiovascular function and use of proteins carbohydrates and fats Mapping the Mind the Brain in Action a Looking at the brain i Electroencephalograph EEG recording of electrical activity ii CT X rays to construct 3D images iii MRI magnetic field to indirectly visualize brain structure iv fMRI visualize brain activity using charges in blood oxygen level v TMS applying strong and quick magnetic fields to the surface that can enhance or interrupt brain function vi b MEG detects tiny magnetic fields