Biological Psychology 2 Biological Psychology 2 Pgs 124 136 Pgs 124 136 Communication in the Brain Communication in the Brain Neurotransmitters Neurotransmitters Communication in the brain Communication in the brain Neurons Neurons Nerve cells specialized for Nerve cells specialized for Parts of a neuron Parts of a neuron Cell body Cell body Dendrites Dendrites Axons Axons Myelin Myelin Cell Body Soma Cell Body Soma Contains cell Contains cell Responsible for maintenance Responsible for maintenance No role in signaling No role in signaling Dendrites Dendrites information from other neurons information from other neurons Dendrites detect Dendrites detect Many per cell Many per cell AxonAxon messages to other neurons messages to other neurons Axons Away Axons Away One axon per cell One axon per cell axon terminals The axon ends at axon terminals The axon ends at Myelin Sheath Myelin Sheath White fatty White fatty Increases speed of neural signals Increases speed of neural signals Fat faster Fat faster How does the myelin sheath work How does the myelin sheath work Large cells with myelin carry info because depolarization happens faster Characteristics of Neurons Characteristics of Neurons Neurons have membrane Neurons have membrane Some molecules pass through but others Some molecules pass through but others can t can t Semipermeable Membrane Characteristics of Neurons Characteristics of Neurons Neurons also have Neurons also have Small openings in the membrane allowing Small openings in the membrane allowing molecules to pass through molecules to pass through Can be opened or closed act as gates Can be opened or closed act as gates Axon Channel s Characteristics of Neurons Characteristics of Neurons Polarized Polarized Electrochemical potential Electrochemical potential Molecules with charge attracted to Molecules with charge attracted to those with charge those with charge So molecules want to the So molecules want to the neuron neuron Graded Potentials Graded Potentials Excitatory or inhibitory Excitatory or inhibitory Excitatory makes neuron more Excitatory makes neuron more Inhibitory makes neuron more Inhibitory makes neuron more Graded Potentials Graded Potentials Inputs add together and can cancel each Inputs add together and can cancel each other out other out Action potential occurs when enough Action potential occurs when enough excitatory inputs to reach threshold excitatory inputs to reach threshold Action Potential Action Potential Continues Down Action Potential Action Potential Requires influx of positive ions Requires influx of positive ions All or none All or none Continues down entire neuron Continues down entire neuron Chain reaction DOMINOES DOMINOES Chain reaction Leads to release of NT s Leads to release of NT s Refractory Period Refractory Period Sending a Neural Signal Sending a Neural Signal Neurotransmitters Neurotransmitters Aid in communication between neurons Aid in communication between neurons Synaptic Cleft Synaptic Cleft Space two neurons Space two neurons Where neurotransmitters released Where neurotransmitters released Chemical Neurotransmission Chemical Neurotransmission NTs released by one 1 1 NTs released by one neuron neuron NTs to 2 2 NTs to receptors of another receptors of another neuron and affect it neuron and affect it Ends by 3 3 Ends by chemical breakdown chemical breakdown of NT s of NT s reuptake of NT s into reuptake of NT s into axon terminal axon terminal Presynaptic Neuron Postsynaptic Neuron How do neurons communicate How do neurons communicate Presynaptic Neuron Receptors Postsynaptic Neuron Action Potential s Neurotransmitter s The Hemispheres of the The Hemispheres of the BrainBrain Right Hemisphere Right Hemisphere Controls side of body Controls side of body Course language skills Course language skills Visuospatial skills Visuospatial skills Left Hemisphere Left Hemisphere Controls side of body Controls side of body Fine tuned language skills Fine tuned language skills Actions Actions Split Brain Surgery Split Brain Surgery Corpus Collusum cut Corpus Collusum cut Difficulties integrating Difficulties integrating info from both info from both hemispheres hemispheres Brain Functions Brain Functions Each part of the brain serves one specific Each part of the brain serves one specific function True or False function True or False brain regions involved in one brain regions involved in one function function functions associated with one functions associated with one brain region brain region Take Home Message Take Home Message Understanding the brain important for Understanding the brain important for psychology psychology Central Nervous system Brain and spinal Central Nervous system Brain and spinal cordcord Peripheral everything else Peripheral everything else Endocrine system controls hormone Endocrine system controls hormone release release Many different brain parts Many different brain parts Forebrain the most advanced Forebrain the most advanced Take Home Message Take Home Message Communication in the brain involves neurons Communication in the brain involves neurons Action potentials travel down the axons and cause the Action potentials travel down the axons and cause the release of neurotrasmitters release of neurotrasmitters NTs communicate between neurons NTs communicate between neurons Different NTs do different things Different NTs do different things The left language and right visuospatial The left language and right visuospatial hemispheres of the brain need to communicate hemispheres of the brain need to communicate Read about Brain Imaging Methods pgs 130 Read about Brain Imaging Methods pgs 130 133 133