The Biology Of the Brain Part 1 any psychological process is founded in biological processes Plato located the mind in the head Artistotle located it in the heart Franz Joseph Gall 1758 1828 physician phrenology using visible features on the skull to make pre directions about a person s character biological perspective work on the connections between biology and psych psych sub fields neuroscience behavior genetics evolutionary the neuron nerve cell transmit messages after stimulation n exicatory signal to the neuron to transmit the information further accelerating happens at dendrites signal between neurons can be inhibitory signal to the neuron to not transmit the information further breaking enhanced by myelination transmission process is sped up the synapse junction b w tip of a sending neurons axon and the dendrite of a receiving neuron gap b w sender and receiver synetic gap action potentials stimulates release of neurotransmitters chemicals that cross the synaptic gap and bind receptors transmitted signal can excite or inhibit next neuron firing central nervous syste brain and spinal cord makes decisions the brain 40 billion neurons 400 trillion synapses neurons cluster into neural networks learning occurs as feedback strengthens connections a bodys communication system consisting of nerves the spinal cord 2 way path conveying information between peripheral nervous system and brain ascending fibers transmit sensory to brain descending fibers transmit motor control information reflexes peripheral nervous system sensory and motor neurons connecting the CNS to the rest of the body gathers information and transmits decisions made by CNS to respective parts of the body muscles glands sensory receptors sensory neurons carry information gathered by sensory receptors to CNS motor neurons carry instructions from CNS to muscles interneurons in CNS intervene between sensory input and motor output two parts of the peripheral nervous system somatic nervous system controls the bodys skeletal muscles autonomic nervous system controls the glands and the muscles of internal organs typically operates on its own sympathetic nervous system arouses the body expends energy in stressful situations heart beat increases parasympathetic nervous system calm you down para paradise will calm