Lecture Guide Chapter 2 Neuroscience and Behavior Mon Sept 24 2012 Gen Psych F12 It is wise to keep in mind that neither success nor failure is ever final Roger Babson Re read the tips for success online tutoring available in 207 Schwartz center Introduction to this Chapter Biological Perspective overlapping area b w biology psychology It s easy to overlook dependency of psychology on biology when all is healthy Superficial understanding on Neuroscience Overview of Nervous System see also figure on page 39 of text or slide Nervous System extensive network of specialized cells that carry to from all parts of body Think communication Within the body with the outside world both getting sharing info Neuroscience Study of the nervous system Examines structure function of neurons nerves nervous tissue Psychologists interested in this and effect on behavior Behavioral Neuroscience interested in relationships on NS to behavior learning aka biopsychology How is it that all of our cells together turn into a functioning feeling human being Study charts on LEARN Structure of the Neuron Neurons basic cell in nervous system Receives sends messages 3 main types but all neurons share the same basic structure May be as many as a trillion neurons in our body 100 billion in brain alone Can function 1000 times in a second Mature neurons do not divide like other cells in body new neurons can be generated neurogenesis But they do change Every time we learn the neurons change neuroplasticity Parts of a Neuron message travel downward in the neuron Dendrites receive detect multiple per neuron Soma cell body maintains life of a cell just 1 near the center on neuron Axon long tube like structure carries message to other cells sends just 1 per neuron Inside myelin sheath helps message move more quickly Neurons can detect from other neurons up to 80 000 other neurons network communication Suggests 10 quadrillion connections in the brain Three Types of Neurons Sensory neuron detects carries info from senses to Central Nervous System Aka afferent neuron 1 Motor neuron carries messages from CNS to muscles Aka efferent neuron remember A comes before E and you have to detect before you can react Interneuron Found in CNS middleman most neurons are interneurons receives info from sensory neuron sends commands to muscles through motor neurons connect coordinate allow A E to talk bulk of neurons in the brain Nerves Bundles of axons in body that travel together Insulated protected in a bundle traveling together Other Types of Brain Cells Glial cells more glial cells than neurons in brain 90 Only 10 neurons Ex Climbing Mt Everest Takes 100 people to get 1 man to the top carrying base camp gear 1 Provide support for neurons to grow on around 2 Deliver nutrients to neurons 3 Clean up waste products dead neurons 4 Some produce myelin to coat axons Myelin sheath fatty substance produced by certain glial cells coats axons to insulate protect speed up neural impulse Clicker the message passes Dendrite cell body axon The function of myelin Speed transmission More of what cells Glial cells Generating the Message Neural Impulse 1 Sending the message within the cell electrical salt molecules changing electrical charge All or none fires completely or not at all Either detects it fires or doesn t detect it won t fire how are different strengths responses indicated Every time it fires it fires w the same amount of power It can fire faster to indicate importance strength 2 Sending the Message to Other Cells Sending message b w cells is chemical Neurotransmitter chemical used to pass message to next cell 2 Neurotransmitters NT how many over 100 identified chemical used to pass message to next cell Each transmitter involved in multiple functions in the brain Think key Synapse synaptic gap Microscopic space between neurons NEURONS DON T TOUCH Receptor sites Holes in surface of dendrites or muscle or gland cells shaped to fit only certain NT Think lock Neuron Communication Neurons must be turned ON and OFF Neurotransmitters do this Excitatory neurotransmitter a chemical message that makes it more likely that a receiving neuron will fire ad an action potential will travel down its axon Inhibitory neurotransmitter A chemical message that prevents or decreases the likelihood that a receiving neuron will fire Chemical substances can affect neuronal communication Agonists chemical that binds to a receptor of a cell and triggers a response by that cell Agonists often mimic the action of a naturally occurring substance Whereas an agonist causes an action Antagonists blocks the action of the agonist Cleaning up the Synapse 1 3 2 3 Central Nervous System CNS includes the brain and the spinal cord Spinal cord a long bundle of neurons that 1 Leaves the brain runs down the length the back 2 Is the main means for transmitting messages b w the brain the body Peripheral Nervous System PNS branches out from spinal cord and brain reaches the extremities of the body A Somatic Nervous System carries sensory info and controls skeletal muscles voluntary movements 1 Sensory pathway afferent transmit info from perimeter of body to CNS 2 Motor pathway efferent communicate info from nervous system to muscles glands B Autonomic Nervous System ANS Controls involuntary movement of heart glands lungs more 1 Sympathetic division fight or flight system Prepares body for action in stressful situations by engaging all of the organism s resources run or confront 2 Parasympathetic division Calms the body after emergency has ended Also directs the body to store energy for use in emergencies THE BRAIN How to study 4 The Hindbrain 1 Medulla 2 Pons 3 Cerebellum Structures Under the Cortex Thalamus Hypothalamus Reticular formation RF Limbic System Hippocampus memory Amygdala fear Cortex the Neo Brain or Neo Cortex Outer covering densely packed neurons 85 of the weight of the human brain is in the cortex 20 billion neurons or more in cortex 300trillion connections in the cortex alone Allows us to see hear think understand involved in higher thought processes the interpretation of sensory input Why is the cortex wrinkled What is that called Corticalization wrinkling of the cortex The newborn brain doesn t have many wrinkles at all As we grow learn the brain wrinkles allows larger of cortical cells to exist in small space inside the skull allows more complicated connections Efficiency Believed that the brain changes to reflect what we learn Cerebral Hemispheres two sections of
View Full Document
Unlocking...