PSYC FEBRUARY 19 2015 Continuation of Chapter 1 3rd variable problem third variable that is responsible for both of those things that was not analyzed Allows you to infer causality o Experimentation investigator manipulates one or more factors independent variables to observe the effects on some behavior or mental process dependent variables Must hold constant control other factors that you aren t interested in CHAPTER 2 BIOLOGY OF MIND It s All About the Brain or is it Phrenology the study of the bumps and bulges on your head used this information to figure out your personality trying to figure out what part of the brain is involved in what function Biological psychology concerned with links between biology and behavior o Sleep dreams o Biological causes of psychological disorders o Drives sex thirst hunger Biopsychosocial model if you want to have an understanding of what leads an individual to behave in a particular way you have to look at o Biology o Individual psychology o Social influences Neural Communication Neurons cells that make up your nervous system nerve cells o Cell body the cell s life support center o Dendrites receive messages from other cells o Axon passes messages away from the cell body to other neurons o Neutral impulse action potential electrical signal traveling down o Terminal branches of axon form junctions with other cells o Myelin sheath covers the axon of some neurons and helps speed muscles or glands the axon neural impulses Types of Neurons the role that each neuron plays is what makes them different from one another based on functionality o Sensory neurons the neurons that are connected to the sense organs input neurons allow you to take information from your environment o Motor Neurons output neurons result in some kind of action running or walking or contraction of organs beating of heart secretion of hormones action isn t necessarily the big large things that we see axons are connected to muscles tissues or other glands o Interneurons the stuff in the middle processors relay messages between other neurons make up your brain and your spinal cord Transmitting Information o Action Potential electrical charge travels down axon o Transduction transforming energy from one form to another How Neurons Communicate o Synapse the space between the axon and the dendrite o Neurotransmitters chemical messengers that are responsible for carrying the message from neuron 1 neuron 2 Real function of the action potential to tell the neurotransmitters to release o Reuptake process neuron 1 axon reabsorbs the neurotransmitters so that they can use them again at a later point in time o Refractory period the time period when the reuptake is going on and the repolarization of your axons is back at its resting state During this period the neuron does not have the ability to fire Table 2 1 in the textbook How Neurotransmitters Influence US pleasure Effects of Drugs Other Chemicals Endorphins natural opiate like neurotransmitters linked to pain control o Agonist something that is similar enough in molecular structure to bind to receptor site and mimic the function Morphine agonist for our body s naturally produced endorphins o Antagonist similar enough in molecular structure to bind to receptor site but not similar enough to mimic the function Prevents the real neurotransmitter from binding to the site and doing the function its supposed to do Nervous System Nerves made up of neurons Bundles of axons that form cables connect the CNS with muscles glands sense organs o Central nervous system brain and spinal cord Spinal cord connects PNS to the brain Reflexes automatic responses to stimuli o No brain involvement o Peripheral and glands Autonomic controls self regulated action of internal organs Sympathetic arousing Parasympathetic calming Somatic controls voluntary movements of skeletal muscles Endocrine System Slow chemical communication system Glands secrete hormones into bloodstream which then effect other tissues Adrenal glands o Epinephrine adrenaline o Norepinephrine noradrenaline o Increase heart rate blood pressure blood sugar Pituitary gland o Controlled by hypothalamus o Influences growth release of other hormones The Brain Older Brain Structures o Brainstem oldest innermost brain region crossover point Medulla breathing blood pressure and pulse control bottom of the brainstem Pons helps with balance and space navigation o Reticular formation reticular activating system controls circadian rhythm sleep wave cycle alert awake or drowsy and tired o Thalamus sensory switchboard information you pick up from your senses goes here and it is redirected to the appropriate part of the brain smell does not pass through here at all Cerebellum nonverbal learning memory time judgment emotion regulation sound and texture discrimination voluntary movement Limbic System o Hypothalamus monitors what s going on in your body helps to o Pituitary gland sends signals to appropriate portion of your body to maintain homeostasis fix something o Amygdala involved in emotions things like fear or anger o Hippocampus controls your memory memory consolidation Newer Brain Structures o Cerebral cortex Cerebrum 2 large hemispheres that make up 85 of brain s weight brain weighs 2 3 pounds Cerebral cortex interconnected neural cells control and information processing center Structure o 20 23 billion nerve cells o 300 trillion synaptic connections o Glial cells support nourish and protect neurons give the brain structure intermediary between blood vessels and brain tissue o Fissures prominent folds that separate the different lobes Cerebral cortex parts Cerebral cortex function o Frontal lobe language thought memory motor functioning voluntary o Temporal lobe language memory hearing form perception o Spinal cord o Occipital lobe visual processing o Parietal lobe touch sensations vision attention o Output motor cortex left hemisphere section controls the body s right side o Input sensory cortex left hemisphere section receives input from the body s right side o Association areas areas involved in higher mental functioning e g learning remembering thinking speaking Integrate info from other parts of the brain