Lec5 Post-Notes PDF
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Uploaded by AngelicCanyon
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X. Liu
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Summary
These lecture notes cover different methods of studying the brain, including techniques like fMRI, EEG, and TMS. The notes discuss the advantages and disadvantages of each method, providing a basic understanding of how these tools are used. The document also briefly discusses the structure of the eye and visual perception.
Full Transcript
How We Study Brain X.Liu PSYC 5130 Today Manipulating & Measuring Brain-Behavior Lesion Stimulation X.Liu PSYC5130 Dr. Wilder Penfield, 1940s X.Liu PSYC5130 Relatively noninvasive brain stimulation Transcranial Magnetic Stimulation (TMS) A small wire coil is placed adjacent to the skull High-voltage...
How We Study Brain X.Liu PSYC 5130 Today Manipulating & Measuring Brain-Behavior Lesion Stimulation X.Liu PSYC5130 Dr. Wilder Penfield, 1940s X.Liu PSYC5130 Relatively noninvasive brain stimulation Transcranial Magnetic Stimulation (TMS) A small wire coil is placed adjacent to the skull High-voltage current pulsed through the coil Magnetic field passes through the skull Causes a population of neurons to depolarize or hyperpolarize X.Liu PSYC5130 Single Neuron Recordings Can directly measure action potential X.Liu PSYC 5130 X.Liu PSYC 5130 X.Liu PSYC 5130 Non-invasive brain recordings EEG (electroencephalography) 同步 the summation of the synchronous activity caused by post‐synaptic potentials of thousands or millions of neurons that have similar spatial orientation X.Liu PSYC 5130 EEG and ERP Brief changes in an EEG signal in response to an experience are called event-related potentials (ERPs) Small, mixed with many other signals Signal-to-noise problem Solution: many repetitions of trials Noise is random, over time cancels out What is left is a consequence of the experience X.Liu PSYC 5130 Benefits of EEG/ERP Can be used to ask developmental questions Excellent time resolution Poorer spatial resolution Relatively inexpensive: ~hundreds of thousands HKD X.Liu PSYC 5130 Magnetoencephalography (MEG) magnetic counterpart of the EEG or ERP Similar benefits, but better spatial resolution But…very expensive X.Liu PSYC 5130 Functional Magnetic Resonance Imaging (fMRI) X.Liu PSYC 5130 How Does MRI Work X.Liu PSYC 5130 X.Liu PSYC 5130 fMRI fMRI is a special type of magnetic scan. As neurons are more active, they use more fuel (oxygen) Changes in the oxygen content of blood alter the magnetic properties of water in the blood X.Liu PSYC 5130 Costs/Benefits of fMRI Excellent spatial resolution 3T MRI: 1-3mm 7T MRI:
