Introduction to the Neuron
a. Neurons contain machinery for extremely active protein synthesis and packing, like liver
and pancreas cells. (Ribosomes in ER, Golgi complex, mitochondria).
b. Microtubules (of and tubulin an
Axon Guidance and Neuronal Regeneration
a. If you cut a frogs optic nerve and rotate the eye, the original targets are re-innervated,
but theres no orientation compensation by the CNS.
b. This suggests a fixed set of cues dire
a. At day 25 the brains just a tube of rapidly proliferating cells.
b. At day 35 flexures develop and post-mitotic neurons migrate away.
c. At day 100 the cerebral cortex has begun to cover the rest of the brain.
Glial Cells of the CNS and PNS
i. Most numerous glial cells, outnumbering neurons 10:1.
ii. Inexcitable, high resting conductance to K+, R.P. of -90 mV.
1. Essentially only permeable to K+.
2. May allow them to remove K+
Cell Death During Development and Synapse Formation
a. About a 75% neuronal survival rate through human gestation.
b. Cells die to match neuron and target cell populations, as error correction, to generate
Somatosensory System: Peripheral Mechanisms
Overview and definitions:
a. Each of the sensory systems consists of a receptor zone followed by alternating
transmission and synaptic zones.
i. Receptor zone is thousands or millions o
Molecular Basis for Pain and Temperature
a. Mechanical force can cause deformation in nociceptor terminals or release of chemicals
from damaged cells that then stimulate APs in nociceptors.
b. Nociceptive neurons must b
Introduction to Cerebral Cortex and Thalamus
a. Access to the cerebral cortex for all sensory inputs except for olfaction occurs via the
i. Even in the olfactory system, where information reaches the cortex without
Functional Neuroanatomy of Brainstem and Cranial Nerves
Brainstem = midbrain, pons, medulla
Dont forget cerebellum behind brainstem, intimately connected with pons
1. Conduit for long tracts of motor, sensory, and