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Modulatory Neurotransmitters. Jack Whylings. Neuromodulation. Classical Neurotransmission: Limited to synapse Neuromodulation : Neurotransmitter released to area Effects many synapses and neurons Neuromodulatory systems often originate from one region. Neuromodulators. Acetlycholine
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Modulatory Neurotransmitters Jack Whylings
Neuromodulation • Classical Neurotransmission: Limited to synapse • Neuromodulation: Neurotransmitter released to area • Effects many synapses and neurons • Neuromodulatory systems often originate from one region
Neuromodulators • Acetlycholine • Dopamine • Serotonin
Alertness and Attention • Acetylcholine promotes alertness • Acetylcholine increases associated with “active thinking” • Acetylcholine plays a role in memory formation • Nicotine binds to acetylcholine receptors • Activates them, acts as a stimulant
Alzheimer’s Disease • Cholinergic cells are some of first to die in Alzheimer’s disease • Removes acetylcholine input into hippocampus • Treatments • Acetylcholinesterase inhibitors • Cause increase in acetylcholine
Reward and Addiction • Ventral Tegmental Area Nucleus Accumbens is “Reward pathway” • Dopamine is released during times of reward • Dopamine becomes predictive of rewards • Addictive drugs increase dopamine release in this pathway • Addiction changes dopamine circuitry
Parkinson’s Disease • SubstantiaNigra Striatum is involved with generating movement • Striatum is part of the motor system, needs dopamine for proper functioning • In Parkinson’s disease, too many substantianigra neurons have died • L-Dopa (dopamine precursor) used to treat Parkinson’s
Sleep and Rythms • Critical factor for sleep state • Promotes wakefulness • Other neuromodulators involved, but serotonin is still considered primary • Serotonin modulates multiple other biological rhythms • e.g. Breathing, motor rhythms
Depression • Serotonin (and other monoamines) are involved in depression • Some treatments increase Serotonin in the brain • SSRIs (Selective Serotonin Reuptake Inhibitors) • MAOs (Monoamine Oxidase Inhibitors)
Conclusions • Neuromodulators are involved in many forms of brain functioning • Drugs affect each system in different ways • Deficits in these systems result in various disorders