PPT revised from M.M-P 大脑皮層切片染色图 细胞核染色 高尔基染色
大脑皮層切片染色图 细胞核染色 高尔基染色 PPT revised from M.M-P
Figure 2.2 Camillo Golgi (1843-1926).(Source: Finger,1994,Fig.3.22.) G Figure 2.5 Santiago Ramon y Cajal (1852-1934)
Cajal's "Neuron Doctrine" 889958R Ramon y Cajal's illustration of the circuits in the hippocampus
Ramon y Cajal’s illustration of the circuits in the hippocampus Cajal’s “Neuron Doctrine
This fiber ends...is an enlargement which may be rounded and subtle,but that may also adopt a conical appearance.This latter we shall name the growth cone,that at times displays fine and short extensions... ...I believe that one could also think of the migration of growth cones like the phenomenon called Pfeffer's chemotaxis......The processes of the neuroblasts become oriented by chemical stimulation,and move toward the secretion products of certain cells. Ramon y Cajal (1898)
Ramon y Cajal (1898) This fiber ends … is an enlargement which may be rounded and subtle, but that may also adopt a conical appearance. This latter we shall name the growth cone, that at times displays fine and short extensions… ….I believe that one could also think of the migration of growth cones like the phenomenon called Pfeffer's chemotaxis...... The processes of the neuroblasts become oriented by chemical stimulation, and move toward the secretion products of certain cells
Neuronal Diversity >1,000(?)specific types of neurons in the human nervous system anatomic/morphologic features,distinct functions,connections Motor neuron from spinal cord Mitral cell from olfactory bulb Pyramidal cell from cortex Dendrite Dendrite Dendrite Cell body Axon Cell body Purkinje cell Ganglion cell Axon Axon Axon Axon Front
Types of neurons:function Component Sensory Motor Local Projection Neuroendocrine Model Signal neuran neuron interneuron interneuron cell neuron Input Excitatory input signal Integrative Integration signal Conduction signal (action potential) Conductile Output or Outpul 2 secretory Capillary signal Muscle Secretion
Labeling of individaul neuron via intracellular loading Purkinje Cell
Purkinje Cell Labeling of individaul neuron via intracellular loading
Genetic labeling of individual Drosophila neurons And in the context of the whole brain
Genetic labeling of individual Drosophila neurons
Individual neurons visualized with "Brainbow" Dentate gyrus Cerebral cortex Purkinje cells in the cerebellum Jeff Lichtman,Harvard University
CLARITY Making biological tissue transparent and chemically accessible Before After The brain is a The brain isa world consisting world consistino of ar er of of a number of un ed unexplored cont and continents and great sches great stretches of unknown of unknown territory. territory. 2 days Can view connections and networks across an entire,intact brain Karl Deisseroth,Stanford University