PSY 1001 1st Edition Lecture 5 Outline of Last Lecture I Major Lobes of the Cortex a Occipital b Parietal c Temporal d Frontal II Examples of Systems a Basal Ganglia b Limbic System c Cerebral Cortex II Some Organizing Principles Outline of Current Lecture I Cells of the Brain II Neuronal Communication a Anatomy of a neuron B Electrical activity of neurons C Synaptic transmission Current Lecture I Cells of the Brain A Two main cell types of the central nervous system i Neurons basic signaling units of the nervous system ii Glial cells provide support functions both chemically and structurally These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute B The brain is an intricate network consisting of approximately 200 billion neurons and more than a trillion glial cells C Each neuron receives and combines multiple inputs to determine whether to transmit an action potential to the next target Parin its network neuron muscle gland or organ II Neuronal Communication A Anatomy of a neuron i Soma cell body ii Dendrites input iii Axon output iv Myelin sheath v Axon terminal vi Synapse a Two components i Electrical due to ions charged molecules ii Chemical due to neurotransmitters b General sequence i Electrical chemical electrical etc c Staging i Dendrite axon dendrite etc B Electrical activity of neurons i Depolarization makes the neuron more likely to fire and action potential inside less negative ii Hyperpolarization makes the neuron less likely to fine an action potential inside more negative iii Action potential is caused by Na rushing in and K rushing out a All or none principle an action potential is either present or it s not C Synaptic transmission i AP causes synaptic vesicles to dump contents into gap synapse between neurons ii Contents are chemicals called neurotransmitter iii Neurotransmitters connect blind to receptors