Nervous System - Biological Psychology - Neurons PDF

NERVOUS SYSTEM DR. SHOURIEHEBAL SONI Asst. Professor SVKM’s Mithibai College Nervous system : Neurones Glial cell Neurones: + Neuron is the basic working unit of brain. + Specialized cell designed to transmit information to other nerve cell , muscle , or gland cells. + Ma...

NERVOUS SYSTEM DR. SHOURIEHEBAL SONI Asst. Professor SVKM’s Mithibai College Nervous system : Neurones Glial cell Neurones: + Neuron is the basic working unit of brain. + Specialized cell designed to transmit information to other nerve cell , muscle , or gland cells. + Mammalian contain 100 billions of neuron. Cont..... Neuron are excitable cell Spanish histologist Ramon, specialized for repetitive said that nerve cells were transfer of membrane independent units rather potential between receptor than an network of cells and affector cell and also interconnected by between neurones. cytoplasmic bridges.  Body (SOMA) neuron cell body generated 2 types of cell processes: 1) Dendrites – received nerve impulses from Structure of sensory cell or other neuron neurons: Axon – convey signal to other cells nucleus, SER , RER , Golgi apparatus, Mt Synapses - Classification of neurones: + Functional classification + On the basis of no. And patterns of cell body + By their size and ratio of nucleus to cytoplasm diameters  Functional classification: Sensory Interneurons Motor types Interneurons : + Projection neurones: Communicates anteriorly and posteriorly to the other neuron + Commissural neurones: send an axon to corresponding location in NS but on the opposite side + Interinsic neurones: Which are confined to same level and side of CNS Projection of axon : + Axon cross to opposite side of body – DECUSSATE + Axon remain on the same side of body – IPSILATERAL + EXAMPLE: rational ganglion cell axon of Vertebrates On the basis of no. And patterns of cell body : 04 types of neurones Unipolar: + Have a spherical soma with single process that bifurcated into dendritic arborization & an axon with terminal synapses. + Example : invertebrates- interneurons and motor neurones + Example: Vertebrates- sensory neurones but also present in cranial spinal ganglia  Bipolar: + Have a dendritic process and an axonal process + Example: sensory neurones Multipolar: Example- many Have no. Of interneurons & dendritic motoneuron + process and few sensory single axon neurones Pyramidal neurons. + These neurons have one axon but several dendrites to form a pyramid type shape. These are the largest neuron cells and are mostly found in the cortex. The cortex is the part of the brain responsible for conscious thoughts. Pseudo unipolar: + Share characterized with both unipolar & bipolar + Single process extended from soma which later branches into 2 distinct structure + Example: sensory neurones – have one axon that branches into 2 extension + a) connect to Dendrites received information + B) Transmit to information to spinal cord By their size and ratio of nucleus:cytoplasm diameters : Small neurons: Giant neurons: Small neurons: + Size : 3 micro in diameter + Nucleus: cytoplasmic ratio close to 1 + Example: globuli cell of invertebrates + Example: granules cell of Vertebrates  Giant neurons: SIZE : 1000 MICRO IN NUCLEUS: EXAMPLE: FAINT DIAMETER CYTOPLASMIC RATIO IS NEURONES OF MARINE 0.5 GASTROPODS + Purkinje neurons- INHIBITORY NEURONS Purkinje neurons have multiple dendrites that fan out from the cell body. These neurons are inhibitory neurons, meaning they release neurotransmitters that keep other neurons from firing. The field of psychology explores how neurons and neural networks give rise to various aspects of human cognition, behavior, and mental processes. + Cognitive Processes + Neurotransmitters and Emotions + Neuroplasticity and Learning + Behavioral Genetics + Neurological Disorders + Neural Imaging and Brain Mapping + Neural Basis of Decision-Making + Biological Basis of Motivation + Neuropsychology + Psychopharmacology