Why do we study the brain/nervous sys?Makes possible everything tht we do, experience and perceiveIt makes us different from the rest of the animal kingdomIts complexity is enormous and far from being completely understoodIt allows interaction between the outer world and mind/process of thinkingThe ultimate function of the brain is to..Output in external pathway from motor sysPhysiological PsychologyBeh neuroscience=the study of the physiological evolutionary, and developmental mech of beh and expBeh neuroscience seeks to describe the physical mech of the body that mediate our movements and mental activityWe want to be able to describe what occursBut the ultimate aim is to be able to explainWhy do we act the way we do? Y are we diff from each other? Y some of us become scientists and others poets?Relationship between the mind and bodyTwo major views of the mind body problemDualism=mind and body are separate but interactingBody is physical, mind is notFrom the belief that spirits can inhabit a bodyMonism=mind is a property of the physical nervous sys (body); an emerging property of the brain is the mindEverything in the universe consists of matter and energy, mind is a result of working cnsOnly one single entityConsciousnessRefers to self awareness and the ability to communicate our thoughts, perceptions, feelings, and memoriesPhysiological approach=consciousness can be affected by drugs, brain trauma, illnessThus conscious is a physiological fn just like our other forms of beh (perception motivation, emotions, memory, motor control)Consciousness and blind sightDamage to the visual sys on one side of the brain will produce blindness in the opposite (contralateral) visual fieldBlind sight: blind patients are unable to see, but are able to reach for objects placed in their blind visual fieldImplies tht we need not be conscious of a stimulus in order to act on tht stimulusIs able to happen to blind patients bc of residual visionEyeprimitive visual sys (a person is not aware of vis info by the sys)prmitive beh mech: eye and head movements, reaching movements w hands, other simple behEyemamalin visual sys (damage abolishes perception and awareness of visual stim)more recently evolved beh mech: speech and thinking in words (and consciousness), other complex behSplit brain procedureCorpus callosum contains bundles of axon fibers that connect one hemisphere to the otherEpilepsy: frequent seizures, the hippocampus is extremely susceptible to being hyperactive and is capable of sending overstimulation to other parts of the brain, as soon as that overstimulation reaches the frontal cortex..initiates seizureCollotomy: cutting the corpus callosum to alleviate epileptic seizuresThe surgeon opens the skull, lays back brains coverings, exposes corpus callosum w cerebral retractor cuts through the corpus callosumW out a corpus callosum, the left and right cerebral hemispheres are unable to directly communicateInfo that doesn’t reach the left hemi (Left =language) does not enter consciousness: the person therefore cannot verbalize itInfo tht enters the right hemi cannot be translated into langTesting a split brainThe olfactory sys is unilateral, thus if a person smells a flower w right nostril it will stay in the right hemi if split brain, is not named bc does not go to left hemiWill, however, pick the flower w left hand when asked what was smelled bc right hemi controls left side of bodyhas not been able to reach consciousnessthe activity of the brain results in the mind, the idea of consciousness. This is what the brain “does”beh neuroscience studies this phenomenaexplain: find the mech that underlie these phenomenaResearch GoalsThe goal of science is to explain the phenomena under studyExplanation involves 2 processes:Generalization=deduction of general laws, using results from experiments (laws to exp individ beh)Reduction=the use of simple phenomena to explain more complicated phenomena (ex: lang is due to act of left hemi)Create models tht could simulate what is happening in the brainRoots of phys psych3000 bc =the dawn of neurologyfirst descriptions of the brain and brain injuries (surgical papyrus)Hippocrates: the father of medicineAll of our emotions are based on the activity of the brainLearning and knowledge, likes and dislikes, come from the brainHippocratic corpus, provided 1st statement about the brain as a controlling center for the bodyAristotleBelieved that the heart was the seat of intellectual and perceptual functions. Brain served to “cool” the heartGalenPerformed dissections, anatomical description of nerves, cerebrum v cerebellum, animal spirits were stored in ventricles (cavities within the brain)RenaissanceThree cavities within the brainRene Descartes17th century French philosopherdualistmind=unique human attribute that is not subject to the laws of the universewas first to suggest connection between mind and its physical housing, brainviewed world as mechanic and viewed human beh in terms of reflexive mech elicited by stimuli in the envproposed tht the mind interacted w the physical body thru the pineal body (not brain tissue, not within brain tissue)viewed hydraulic pressure within nerves as the basis for movementEra of cortical localizationFranz joseph gall=phrenology, individual development of cortex was reflected in bumps and depressions of the skulllocalization of fn of the brainLocalization of functionMuller(1808-1858)=noted that specific nerves carry messages from different sensations (Doctrine of Specific Nerve Energies)ex: stimulation of the retina will always produce a visual image (seeing stars), every “line is labled”Florens used ablation (removal of discrete brain areas) in animals to asses the role of the brain in control of behCaveat: may reach the wrong conclusion, may be removing a central part of the sys for fn but may not be esp (roach)Flourens reported discrete brain areas that controlled heart rate and breathing, purposeful movements, and visualPaul BrocaDemonstrated tht cancer cells can spread throughout the bloodLeborgne (Tan) patient w paralysis on the right side of the body, progressive loss of speechShowed major deficit in stroke (aphasia)Broca’s autopsy of Tans brain noted damage in the left hemiBroca’s areaElectrical stim of the brainFritsch and hitzig applied electrical stim to cortex in dogs to elicit muscle contraction on the opposite side of the body (contralateral)Identified the primary motor cortex=region