Methods of Neuroscience Lesson 2

Studying the Brain & Behavior Anatomy & behavior Damage  behavior changes Structural differences  behavior Activity & behavior Behavior  record activity Change activity  behavior? Correlation vs experimentation causality ~

Brain Damage & Behavior Correlate damage  behavioral change Clinical Neuropsychology Broca’s aphasia Experimental ablation Lesion brain  behavior change? Lashley & the engram Problems: variability location of damage spared behaviors/abilities multiple areas & tracts involved post mortem ~

Anatomy & Behavior: Modern Techniques Noninvasive Computerized axial tomography CAT (CT) scan x-rays of brain Low resolution Magnetic Resonance Imaging (MRI) higher resolution than CAT spinning H atoms radio waves ~

Tracing & Labeling Stains, radio-isotopes Amino acids, antibodies, etc. Tracing connections Via axonal transport Antero- & retrograde Labeling structures Receptors, genes, etc. ~ N: motor axons (green), neuromuscular synapse (orange) O: DRG  spinal cord A: visual cortex Substance P receptors in dorsal horns

Normal Brain Differences Sexual dimorphism corpus callosum hypothalamus Sexually Dimorphic Nucleus - SDN ~

Brain Activity & Behavior Record activity during behavior EEG electroencephalograph reads electrical activity of brain Ayahuasca – from South American vine; psychedelic drug; 5-HT agonist, DMT dimethyltryptamine

PET Scans Positron Emission Tomography metabolic activity radioactive 2-deoxyglucose Disadvantages spatial/temporal resolution ~

fMRI Functional MRI detects increases in oxygen use Advantages anatomy & activity High resolution spatial & temporal Disadvantages Difficulty interpreting activity level ~

Electrical Stimulation of Brain (ESB) Change activity  change behavior? Fritz & Hitzig Olds & Milner neurosurgery Advantage experimental Disadvantage invasive ESB during Neurosurgery Map function minimize loss ~

Experimental Psychopharmacology Chemically change activity learn about drugs or use drugs to learn about brain & behavior Block dopamine receptor movement effects? learning effects? Combine with behavioral tests ~

Behavioral Psychopharmacology Prenatal exposure to methamphetamine effects on learning?

Cellular imaging Radioactive labeling similar idea to PET Cellular changes during learning role of Ca++ ions ~

Genetic Techniques Knock-out Mice Genes change microanatomy alter function Disable gene  no protein receptor, enzyme, etc evaluate effect on behavior Obesity Alcoholism ~