Split brain ProceduresWhen the Corpus Callosum is severed there cannot be communication between the 2 hemispheresIn virtually all people, language is in the left hemisphereIf someone with a split brain procedure has their right eye covered, asked to use their left eye and a stimulus is flashed on the left visual field of the person, they would not be able to vocalize what was there, but when asked to use their left hand to draw, choose from multiple options, or write, the left had will chose the correct answerInformation coming in from the left visual field will go to the right hemisphereThe right hemisphere in a non-split brain individual would then send the information to the left hemisphere where language is locatedSince the connection has been severed, the info cannot be transferred, and the hemisphere does not know what to vocalizeBut leave the left hand (the right hemisphere) chose non-verbally, it invariably knows the answerNeuronsThe structures that build the entire brain and nervous system going throughout the periphery as wellMost cells are comprised of a cell bodyUnlike other cells they haveNeurons exhibit a variable number of protruding processes or extensions from the cell body called Neurites, which includes:Dendrites: variable in number and branching in nature; branch out away from the cell body; receive information from other cellsAxons: typical a single process, sends out information to other neurons, muscles, or glandsMyelin Sheath: fatty tissue on the axon; speeds up the information transfer process; the thicker the axon, the faster the process; terminal branches branch onto other cells’ dendritesSynapses: the junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron. The tiny gap at this junction is called the synaptic gap/cleftSquid giant axon videoAllowed for scientists to look into the neuronWhen stimulated, the muscle/muscle tissue=pulsatedThe giant axon controls anti predator behaviorAxons vs DendritesAxonsSends out infoSmooth surfaceGenerally only one axon per neutron, sometimes noneNo ribosomesCan have myelinBranch further from the cell bodyDendritesConveys info to the cell bodyRough surface (dendritic spines)Generally many dendrites per neuronContains ribosomesNo myelinBranch near the cell bodyDirectional flow of info in most neuronsSynapsedendrite soma (“cell body”) axonsynapseThreshold of ExcitationThreshold of excitation: value of potential (level of depolarization) at the axon hillock that must be reaches to generate an action potential; the level of polarization to receive an action potential (the sending of a message); if the stimulus does not reach the threshold, there will be no depolarization and no action potentialAxon hillock: where the axon and the cell body met; the most sensitive part of the axon during depolarization (sending of action potential)The resting potential for a cell is -70 millables (the cell is not firing; normal resting behavior)Graded potential: sub-threshold changes in the membrane potential, the magnitude of which is related to the strength of the stimuli (or inputs)Depolarization: A change in the electrical charge in the positive direction from the resting state (a “decrease” in negativity)Hyperpolarization: a change in the electrical charge in the negative direction from the resting state (an “increase” in negativity)Refractory period: the amount of time of “rest” needed between action potentialsAction potential: A brief electrical impulse that provides the basis for the conduction of information along an axonAll-or-None Response: the neuron either fires in a full blown response or no response occurs; the way to tell intensity of a stimulus (ie. A slap versus a tap) is by the number of action potentials that are fired; the more axons engaged the stronger the stimulus is perceivedEach time the neuron fires (action potential) it transmits an impulse of the same amplitude (size and shape) and speedThe characteristic of the action potential is independent of the intensity of the stimulus that initiated it; so long as the stimulus is sufficient to exceed the thresholdSynaptic CleftChemicals that are similar to the chemicalAntagonist: blocks the neurotransmitter, the chemical fits the neurotransmitter but cannot cause a reaction, but it does block the neurotransmitter from being used and fire a responseExamples of neurotransmittersDopamineSerotoninNorepinephrineG.A.B.A: the major inhibitory neurotransmitter; a reduction of firing in the post synaptic cell; results in a reduction of firing in the post synaptic cellEndorphins: nature opiates that occur in the body that deal with pain and pleasureThe release of all of these neurotransmitters is not only dependent on chemical processes but also on experience/expectancyTone/shock pairing= eventually the tone itself will elicit the release of endorphins in expectancy of the shockCaffeine is an adenosine antagonist; blocks receptors associated with adenosine= you don’t get drowsyCaffeine boosts dopamine= coffee highEmotionsStates of feeling that can affect behavior (action oriented)Emotions can amplify/drive actionsArise due to extrainious external stimuliThey can occur spontaneously (depressed people)Valence (positive-negative):Anything that is biological is physchologicalTwo dimensionsValence (positive=pleasant; negative=unpleasant); “vertical range”Arousal (low arousalhigh arousal)Emotions and Autonomic Nervous SystemSympathetic vs parasympathetic= balanceClassification of EmotionsHigh, Medium, Low (by intensity)i.e. ecstasyjoyhappiness or pensivenesssadnessgriefSame valence but different intensity levelsTheories of emotionDoes your heart pound because you are afraid? Or are you afraid because you recognize the emotional response?Perception of stimulusperception of dangeremotional changespecific pattern of autonomic arousal (heart races…)Stimulusperception of dangerspecific pattern of autonomic response (heart racing…)Particular emotion experienced (fear) –JamesJames-Lane Theory of Emotion:Emotion arises from autonomic responsesCannon Barb theoryStimulusperceive and interpret as generalsimultaneous autonomic and emotional response; perception of danger=causationSchachter Two-Factor TheoryTheory that is “nice, useful” because it uses cognition, unlike the others, in producing emotion/producing autonomic changesExternal stimuli (sight of oncoming