PSY 251 Lecture Notes - Lecture 4: Axon Hillock, Fourth Ventricle, Axon Terminal

• School: Miami University
• Department: Psychology
• Course: PSY 251
• Professor: Kochli Daniel

Document Summary

Exam: thursday, 9/22/16: structure and function of the cells of the nervous system. Axon: action potential propagation, myelin speeds up signaling. Na+, cl- higher outside the cell, k+ higher inside the cell: classification. Function: sensory neuron (afferent), motor neuron (efferent), interneuron. Structure: unipolar (1 divided axon on soma), bipolar (1 axon, 1 dendrite on soma), multipolar (1 axon, many dendrites on soma) Glial cells: astrocytes: support, clean up, endfeet associate with blood vessels, nourishment, microglia: smallest, mediate cns immune response, phagocytosis, oligodendrocytes: cns only!!! 1 oligodendrocyte makes ~ 50 myelin segments speed up signal conduction: schwann cells: pns only!!! 1 schwann cell only makes 1 myelin segment. Blood-brain barrier: semi-permeable barrier, large/charged molecules cannot cross into brain, only small, uncharged molecules and fat-soluble molcules can pass through, area postrema = permeable section to get rid of toxins. Communication: stimulus sensory neuron interneuron (spinal cord) motor neuron effector muscle. Other interneurons can inhibit the motor neuron via brain signals.