1 / 30

Neuroscience: Exploring the Brain, 3e

Neuroscience: Exploring the Brain, 3e. Chapter 15: Neuroendocrine system: Chemical Control of the Brain and Behavior. Introduction. Synaptic Connections Point-to-point Restricts synaptic communication Brain areas with expanded influence over space and time Secretory hypothalamus

cissy
Télécharger la présentation

Neuroscience: Exploring the Brain, 3e

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Neuroscience: Exploring the Brain, 3e Chapter 15: Neuroendocrine system: Chemical Control of the Brain and Behavior

  2. Introduction • Synaptic Connections • Point-to-point • Restricts synaptic communication • Brain areas with expanded influence over space and time • Secretory hypothalamus • Autonomic nervous system (ANS) • Diffuse modulatory systems

  3. The Secretory Hypothalamus • Function • Difference between hypothalamus and dorsal thalamus • Hypothalamus defect • Fatal disruption to body function • Dorsal thalamus defect • Blind spot, lack of feeling

  4. The Secretory Hypothalamus • Homeostasis • Regulatory process: Regulates body temperature and blood composition • Hypothalamus commands in cold weather • Shiver, goosebumps, turn blue • Hypothalamus commands in hot weather • Turn red, sweat

  5. The Secretory Hypothalamus • Structure of the Hypothalamus

  6. Pathways to the Pituitary Two neurohormones Oxytocin Lactation, suppress hypothalamic function Vasopressin Regulate blood volume and salt concentration The Secretory Hypothalamus: Neurosecretory neurons of the periventricular zone.

  7. The Secretory Hypothalamus • Communication between kidneys and brain

  8. The Secretory Hypothalamus • Hypothalamic Control of the Anterior Pituitary • Controlled by parvocellular neurosecretory cells • Secrete hypophysiotropic (‘releasing’) hormones • Hypothalamiopituitary portal circulation • Pituitary cells secrete or stop secreting hormones

  9. The Secretory Hypothalamus • Stress Response • Periventricular hypothalamus secretes CRH into portal circulation. • ACTH released into circulation. • ACTH stimulates cortisol release from adrenal cortex.

  10. The Autonomic Nervous System • Divisions of autonomic nervous system (ANS) • Sympathetic division • Increased heart rate and blood pressure • Depressed digestive function • Mobilized glucose reserves • Parasympathetic division • Slower heart rate, fall in pressure • Increased digestive functions • Stop sweating

  11. The Autonomic Nervous System • ANS Circuits versus Somatic Motor System

  12. The Autonomic Nervous System • Sympathetic and Parasympathetic Divisions

  13. The Autonomic Nervous System • The Enteric Division • Location: Lining of esophagus, stomach, intestines, pancreas, and gallbladder • Composition: Two complicated networks- myenteric (Auerbach's) plexus and submucous (Meissner's) plexus • Function: Control physiological processes involved in transport, digestion of food • Inputs: From brain via axons of the sympathetic and parasympathetic divisions

  14. The Autonomic Nervous System • Central Control of the ANS • Connections for autonomic control • Periventricular zone connections to brain stem and spinal cord nuclei • Nucleus of solitary tract • Function of solitary nucleus • Integrates sensory information from internal organs and coordinates output

  15. The Autonomic Nervous System • Neurotransmitters and the Pharmacology of Autonomic Function • ANS: Better understanding of drug mechanisms influencing synaptic transmission (vs. CNS) • Preganglionic Neurotransmitters • ACh: Binds to nAChR, evokes fast EPSP • Ganglionic ACh: Also activates mAChR, slow EPSPs and IPSPs • Preganglionic terminals: Small EPSPs

  16. The Autonomic Nervous System • Postganglionic Neurotransmitters • Parasympathetic: Release Ach • Local effect • Sympathetic: Release NE • Far-reaching effects • Parasympathomimetic: Mimic or promote muscarinic actions of ACh or inhibit actions of NE • Sympathomimetic: Mimic or promote NE actions or inhibit muscarinic actions of ACh

  17. The Diffuse Modulatory Systems of the Brain • Anatomy and Functions • Four systems with common principles: • Small set of neurons at core • Arise from brain stem • One neuron influences many others • Synapses release transmitter molecules into extracellular fluid

  18. The Diffuse Modulatory Systems of the Brain • Anatomy and Functions • Four systems with common principles: • Noradrenergic Locus Coeruleus • Serotonergic Raphe Nuclei • Dopaminergic Substantia Nigra and Ventral tegmental Area • Cholinergic Basal Forebrain and Brain Stem Complexes

  19. The Diffuse Modulatory Systems of the Brain • Noradrenergic Locus Coeruleus

  20. The Diffuse Modulatory Systems of the Brain • The Nonadrenergic Locus Coeruleus • Path: Axons innervate cerebral cortex, thalamus, hypothalamus, olfactory bulb, cerebellum, midbrain, spinal cord • Function: Regulation of attention, arousal, sleep-wake cycles, learning and memory, anxiety and pain, mood, brain metabolism • Activation: New, unexpected, nonpainful sensory stimuli

  21. The Diffuse Modulatory Systems of the Brain • The Serotonergic Raphe Nuclei

  22. The Diffuse Modulatory Systems of the Brain • The Serotonergic Raphe Nuclei • Path: Innervate many of the same areas as noradrenergic system • Function: Together with noradrenergic system, comprise the ascending reticular activating system. Raphe system particularly involved in sleep/wake cycles. Also mood • Activation: New, unexpected, nonpainful sensory stimuli

  23. The Diffuse Modulatory Systems of the Brain • Dopaminergic Substantia Nigra and Ventral Tegmental Area

  24. The Diffuse Modulatory Systems of the Brain • Dopaminergic Substantia Nigra and Ventral Tegmental Area • Substantia Nigra • Projects to the striatum • Facilitates the initiation of voluntary movements(Parkinson’s Disease) • Ventral tegmental area • Innervates circumscribed region of telecephalon • Mesocorticolimbic dopamine system: Dopaminergic projection from midbrain

  25. The Diffuse Modulatory Systems of the Brain • Cholinergic Systems

  26. The Diffuse Modulatory Systems of the Brain • Cholinergic Systems • Basal forebrain complex • Core of telencephalon, medial and ventral to basal ganglia • Function: Unknown, participates in learning and memory • Pontomesencephalotegmental complex • Releases ACh • Function: Regulates excitability of thalamic sensory relay nuclei

  27. The Diffuse Modulatory Systems of the Brain • Drugs and the Diffuse Modulatory Systems • Psychoactive drugs: Act on CNS • Many drugs of abuse act on modulatory systems • LSD, Psilocybe mushrooms, and peyote close to structure of serotonin • Cocaine and amphetamine affect dopaminergic and noradrenergic systems - sympathomimetic

  28. The Diffuse Modulatory Systems of the Brain • Stimulants: Block reuptake • Cocaine targets DA reuptake • Amphetamine blocks NE and DA reuptake and stimulates DA release

  29. Concluding Remarks • Three Components of the Nervous System That Have Great Reach of Their Influences • Secretory hypothalamus (all over the body) • Autonomic nervous system (all over the body) • Diffuse modulatory systems (all over the brain) • Detailed level • Each system performs different functions • General level • All work to maintain brain homeostasis

  30. End of Presentation

More Related