PSYC 310 1st Edition Lecture 3Outline of Last Lecture I. Neurons (the science behind them)II. Neurons (How they Communicate)III. Localization of FunctionOutline of Current Lecture I. Language & Brain ImagingII. Event Related PotentialIII. Representation in the BrainCurrent LectureI. Language & Brain Imaginga. Language production is impaired by damage to Broca’s area (Frontal lobe)b. Language comprehension is impaired by damage to Wernicke’s area (Temporal lobe (generalization))c. New Hypothesis: Form vs. Meaning – Broca’s area involved with comprehension too in regard to form. Relationships of words in sentence. Broca’s Aphasia. Wernicke’s Aphasia.d. Distributed processing in the brain: Specific functions are processed by many different areas of the brain (Many different areas may contribute to a function)e. Positron Emission Tomography (PET)i. Blood flow increases in areas of the brain activated by a cognitive taskii. Radioactive tracer is injected into person’s bloodstreamiii. Measures signal from tracer at each location of the brainiv. Higher signals indicate higher levels of brain activityf. Subtraction technique (starting point of what you are measuring): measures brain activity before and during stimulation presentationi. Difference between activation determines what areas of the brain are active during manipulationg. Functional Magnetic Resonance Imaging (fMRI)i. Typically uses subtraction technique, alternative is pattern matchingThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.ii. Measures blood flow through magnetic properties of blood, oxygenated blood responds differently than deoxygenated bloodiii. Advantage over PET – no radioactive tracer!iv. Disadvantages: indirect method, costly, large, measures blood flow which makes it not so reliable with time courseh. Event Related Potential (ERP):i. Neuron firing is an electrical event. ERP Measures electrical activity on the scalp and makes inferences about underlying brain activity (Needs a lot of trials)ii. Advantage: Continuous and Rapidiii. Disadvantage: Does not give precise location, Interference from electrical devices, slight distance away from neurons, time consuming to set upII. Representation in the Braina. Feature Detectors: Neurons that respond best to a specific stimulusb. Hubel & Wiesel (1965)i. Simple Cells: Neurons that respond best to bars of light of a particular orientationii. Complex Cells: Neurons that respond best to an oriented bar of light with a specific lengthc. Old Hypothesis: Specificity Codingi. Representation of a specific stimulus by firing of specifically tuned neurons specialized to just respond to a specific stimulus (ex: Grandma Neuron)d. Modern Hypothesis: Distributed Codingi. Representation by a unique pattern of firing across a number of neuronsii. Allows for much more information to be represented with a limited number of