The Nueron diagram link below The cell membrane selectively permeable which means it only allows some things in and not other cell membrane keeps positively charged ions outside Positively charged sodium ions accumulate outside and cell membrane will not let through only under certain circumstances see below as to why o the positive sodium ions rush into the cell membrane because they are attracted to the negatively charged ions within the cell membrane a segment of the cell membrane becomes depolarized when positive ions come in o once depolarization occurs depolarization travels from segment to segment one at a time and travels down the axon o this process is also known as cell firing Lil cells the hotdog looking objects in diagram acts like plastic coating on an electrical wire it insolates the wire Prevents cross circuiting and speeds transmission down the axon Depolarization skips over part of the axon that is mylonated this makes the process faster Neuron travels at speeds from 2 10 meters sec to 160 meters sec 260 mph Synaptic gap there is no physical connection here so the electrical chain is broken information must be transferred chemically instead of electrically This largely affects mind behavior mental health and illness Information travels chemically through neurotransmitters o Neurotransmitters very similar to hormones almost identical serve similar function and often have similar chemical structure navigate across the synapse o Neurotransmitter is a protein its serotonin has a particular physical shape there is a docking site for serotonin at the other end of the synapse which is shaped to fit the serotonin like a key lock relationship Dopamine does not fit in these receptor docks All drugs work by modulating what is going on in the synapse Endorphins endoginous morphines neurotransmitters which dock at endorphin receptor sites Morphine is so similar to endorphins that it is capable of docking at endorphin sites which is how the drug works Serotonin generally inhibitory but not always often involved in the regulation of mood and emotion Too little serotonin has been associated with depression loss of anger control and trouble sleeping Halucogens dock at serotonin docking sites and and block the influence of it Dopamine generally has an inhibitory function but not always Cocaine opium heroin all dock at endorphin receptor sites and increase dopamine levels in system o Too much dopamine in frontal lobes of brain frontal lobes are vital to processing is associated with schizophrenia o Too little dopamine is associated with parkinsis Cant target a specific location of a neurotransmitter meaning cant lower dopamine in just the frontal lobe o If targeting were possible it would open many doors and lead to many capabilities Parkinsis nervous control of the body often breaks down The brain is isolated from the bloodstream by the blood brain barrier o This allows certain cell molecules to cross o Dopamine injections do not work because it is water soluble which wont allow it to reach destination L dopa precursor of dopamine fat soluble can pass the blood brain barrier Problem side affects because if you increase dopamine levels in one part of the brain they also rise in other areas
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