Identify Principle Parts of the Brain

 Identify the principle parts of the nervous system  Describe the cells that make up the nervous system  Describe what starts and stops a nerve impulse (action potential)  The role of neurotransmitters  Compare the functions of the CNS & PNS  Identify the principle parts of the brain

 Brain receives incoming info from spinal cord and nerves  integrates/processes info and  generates responses  3 anatomical & functional divisions 1) Hindbrain – basic autonomic and vital tasks 2) Midbrain – muscle groups, responses to sights & sounds 3) Forebrain – receives & integrates sensory input & determines our more complex behavior

 Connected to spinal column  Oldest, most primitive brain division  Most similar among animals  Structures: 1) Medulla oblongata 2) Cerebellum 3) Pons

 Controls autonomic functions ◦ Heart rate ◦ Blood pressure ◦ Respiratory information – O 2 & CO 2 levels ◦ Cough reflex ◦ Swallowing ◦ Sneezing ◦ Vomiting  This is where the neurons cross over to the other side and the left brain controls the right side of the body and vice versa

 Located just behind the medulla oblongata and coordinates basic (unconscious) movements  Ensures that antagonistic muscles don’t contract at the same time  Stores sequenced information – tying shoes  Receives sensory input from joint & muscle receptors, balance & position receptors in ear and visual receptors  Excess alcohol disrupts these functions

 Located just above and partly surrounding the medulla oblongata  Contains groups of axons that extend from the cerebellum to the rest of the CNS &  Coordinates the flow of information between the cerebellum and the higher brain centers  Aids the medulla oblongata in regulating respiration

 Visual & auditory sensory input passes through the midbrain before being relayed to the higher brain centers  Coordinates movements of the head related to vision and hearing (e.g. turning towards sound or flashing lights)  Controls eye movement and pupil size  Monitors unconscious movement of skeletal muscles (smooth moves)  Reticular formation located here-neuron bundle aids in posture, balance & muscle tone, level of wakefulness

 Emotions  Conscious thought  Parts: 1) Hypothalmus 2) Thalmus 3) Limbic system 4) Cerebrum 5) Glands – 2 – pineal, pituitary

 base of forebrain just above midbrain  Coordinates some autonomic fxns, pituitary gland, water & solute balance, T control, carbohydrate metabolism, breast milk production  Monitors sensory signals: sight, smell, taste, noise, body T  Hunger center  Thirst center

 Together w/hypothalmus maintains homeostasis & processes information  Accepts sensory signals & channels them to cerebrum for interpretation (e.g. thalmus may have a consciousness of pain but does not know the location of the pain – the cerebrum interprets the signal and we know where it hurts)

 A group of neural pathways that connects parts of the thalmus & hypolthalmus & inner portions of the cerebrum  “border” – to describe structures that bordered the basal regions of the cerebrum – but has come to describe all neuronal structures that control emotional behavior and motivational drives  Limbic activities are monitored by hypothalmus and modified by cerebrum (social norms)

 Most developed brain region  Language  Decision making  Conscious thought  Left and right cerebral hemispheres are connected in the middle by the corpus callosum = enables 2 hemispheres to share sensory-motor info

 Consists of an outer layer of mostly gray matter (unmylenated CNS neurons, neuroglial cells)  Inner portion consists of white matter containing mylenated nerve axons connecting the lower brain area to the cerebral cortex

 This structure - inner section of ascending and descending axons and an outer layer of cells – makes it ideally suited to ◦ direct incoming info to the proper brain region for processing ◦ Integrate and process info ◦ Route outgoing motor activity to appropriate areas of the body