1. Nervous System Functions Organization –CNSCNS –PNSPNS Tissue Nerve Impulse Reflexes Talking nerves

2. Functions Sensory input (sensory receptors to monitor stimuli) Integrations (processing and interpreting input) Motor output (effects a response)

3. Sensory Input Special organs receive information from environment and send it to brain

4. Integration Making “sense” out of sensory input Electric guitar example

5. Motor Output Response to stimuli The sound from the amp of the guitar example

6. Organization (Structural)

7. Organization (functional)functional

8. Organization (functional) Afferent (sensory) division – conveys impulses to the CNS from receptors Efferent (motor) division – carries impulses from the CNS to muscles and glands –Somatic NS – voluntary control –Autonomic NS – involuntary control

9. Nervous Tissue Structures –NeuronsNeurons –neuroglianeuroglia

10. Neuron

11. 3 Forms –Efferent neurons (motor neurons)Efferent CNS to muscles/glands –Interneurons (connect efferent and afferent) –Afferent neurons (sensory neurons) Receptors to CNS

12. Neuroglia Supporting cells that don’t transmit impulses –Ex. Myelin sheath, made of Schwann cells Insulates neurons and speeds up signal

13. Nerve Impulse Neuron polarized (resting state where more Na+ on outside and more K+ inside Action potential created by depolarization of a neuron when Na+ swept into cell through membrane All or nothing

14. Nerve Impulse K+ ions diffuse outside the membrane to restore electrical condition so that neuron is repolarized back to resting state Na+/K+ pump restores initial concentration of ions inside and outside the neuron

17. Reflexes Rapid, predictable, involuntary response to stimuli Occurs on pathways called reflex arcs Impulse travels from receptor to afferent neuron to spinal cord Automatic reflexes – smooth muscle, cardiac muscle, glands Somatic reflexes – skeletal muscle

18. Central Nervous System protection

19. Cerebral Cortex Largest region Ridges (gyri) and grooves (sulci and fissures) 2 hemispheres seperated by corpus callosum

20. Cerebral Cortex Lobes

21. Frontal Centers for complex reasoning and language comprehension Motor area for speech and primary motor skills

22. Parietal Centers for speech, reading, and primary sensory area

23. Temporal Centers for memory, smells, language formation/comprehension and hearing

24. Occipital Visual association

25. Interbrain Diencephalon Thalamus = relay station for sensory impulses Hypothalamus = regulates automatic nervous responses like water balance, metabolism, thirst, temperature –Also center for emotions and “drives”

26. Brain Stem Pons: breathing Midbrain: vision and hearing Medulla oblongata: heart rate, blood pressure, breathing, swallowing, vomitting Reticular formation: conciousness (importance filter) and wake/sleep cycles

27. Cerebellum Coordinates skeletal muscle activity and balance Guages “intentions” vs. present body positions

28. Protecting the Brain Skull Meninges = 3 connective tissue membranes surrounding the brain and spinal cord

30. Protecting the Brain Cerebrospinal fluid (CSF) = constantly circulating liquid that forms a cushion –Plasma-like –Extracted during spinal taps for testing Blood Brain barrier = relatively impermeable series of capillaries in the brain

31. Peripheral Nervous System Composed of thousands of nerves (bundled neurons) Cranial Nerves – stem from the brain and primarily serve neck and head (12 pair) Spinal Nerves – stem from the spinal column and serve as message carriers for the rest of the body (31 pair)

32. Peripheral Nervous System Somatic – voluntary control of bodily functions –Ex. Muscular control Autonomic (Involuntary) Nervous System – regulates smooth and cardiac muscles and glands

33. Autonomic Nervous System Homeostasis of the body is dependent of ANS and balance of its 2 divisions Sympathetic – fight or flight response Parasympathetic – “rest and digest” mechanism

34. Nerve-Nerve Communication Axon terminal – Dendritic connection Space in between is called SYNAPSE Chemical signal that spans the gap is a NEUROTRANSMITT ER Once signal is transferred, neurotransmitters are reabsorbed.

35. Synapse Action

36. Depression and SSRI’s Normal bodies produce a certain amount of serotonin Chemical depression usually deals with a lack of serotonin

37. Depression and SSRI’s To combat this, SSRI drugs (selective serotonin reuptake inhibitors) prevent the reabsorption of serotonin after it travels into the synapse.