Protection of CNS Bone Blood-Brain Barrier least permeable capillaries in body (allows only water, glucose, and a.a. to pass thru) Useless against fat-soluble molecules (alcohol, nicotine, anesthesia, etc) CSF Ventricles - 4 chambers filled w/CSF CSF – surrounds exposed surfaces of CNS, cushions and supports, transports nutrients, chemical messengers and waste products Meninges – series of layers covering CNS Protects against shock, infection, friction Delivers O 2 and nutrients to meninges, 3 Layers Dura Mater Outermost, Tough fibrous layer Fused to periosteum of skull Subdural space – lymph fluid Arachnoid Subarachnoid space - CSF Pia Mater Bonds to underlying neural tissue Extensive circulatory supply
Main Parts of the Brain Cerebral Hemispheres Diencephalon Brain Stem Cerebellum
Cerebral Brain Structures Gyrus – elevated ridges Sulcus – shallow groves Fissure – deep groove that separates large regions of the brain (ex. Longitudinal fissure separates L/R hemispheres)
Cerebral Structure Cerebral cortex - gray matter Cerebral White matter – nerve fibers Corpus Callosum – connects the cerebral hemispheres Ganglia Bodies – islands of gray matter
Cerebral Cortex Primary sensory, motor, and association cortex Sensory – initial site for conscious sensation Motor conscious control of skeletal muscles (damage causes paralysis) Association Integrates all sensory inputs allowing conscious perception and planning of responses Cognition – attention, language, social behavior and other higher processes
Frontal Lobe Functions Reasoning, planning, parts of speech, movements, emotions, problem solving 4 functionally distinct areas Primary motor cortex (most posterior) Arousal/motivation (medial frontal) Social behavior (orbital frontal) Language comprehension (inferior lateral) Working memory (dorsolateral) Broca’s Area – ability to speak
Parietal Lobe Functions Posterior to central sulcus Integrates sensory information (sensory homunolculi) Visual spatial processing Calculating, writing, right/left orientation Naming and word recognition Drawing
Temporal Lobe Auditory Perception Receptive component of language Declarative and visual memory Emotions Olfactory area Area of Wernicke – speech area
Occipital Lobe Primary visual cortex Responsible for visual processing
Diencephelon (Interbrain) Thalamus Relay station and controls sensory inputs to cerebral cortex Acts w/brainstem to control state of arousal Participates in coordination of movements Hypothalamus (floor) Homeostasis regulation, body temperature, appetite, thirst Control of autonomic nervous system Regulates secretion of hormones including control of pituitary gland Epithalamus (roof) Houses pineal body CSF is formed here
Brain Stem 3 Parts: Midbrain Reflex centers for vision and hearing Pons “Bridge” – fiber tracts Nuclei involved in control of breathing Medulla Oblongata Merges w/spinal cord Fiber tract area Regulates hr, bp, breathing, swallowing, and vomiting RAS (Reticular Activating System) – gray matter thru brain stem controls consciousness and wake/sleep cyles
Cerebellum Coordination and accuracy of complex movements and balance Procedural memory
The Spinal Cord Controls spinal reflexes Diameter decreases as it descends Except at cervical enlargement And lumbar enlargement Central canal – filled w/ CSF Gray matter – glial cells, cell bodies of neurons Horns extend out into horns White matter – myelinated and unmyelinated axons Ascending tracts – sensory info to brain Descending tracts – motor commands to spinal cord
What is the general name that describes the pons, medulla and midbrain? A. Diencephalon B. Cerebellum C. Cerebrum D. Brain stem
A. Diencephalon B. Cerebellum C. Cerebrum D. Brain stem E. Frontal Lobe In terms of volume, the largest part of the brain is
A. Frontal Lobe B. Parietal Lobe C. Temporal Lobe D. Occipital Lobe E. Cerebellum F. Brain Stem Which lobe is primarily responsible for somatosensation?
A. Frontal Lobe B. Parietal Lobe C. Temporal Lobe D. Occipital Lobe E. Cerebellum F. Brain Stem Which lobe contains the primary visual cortex?
A. Frontal Lobe B. Parietal Lobe C. Temporal Lobe D. Occipital Lobe E. Cerebellum F. Brain Stem Damage to which lobe can produce disruptions to social and emotional behavour?
A. Frontal Lobe B. Parietal Lobe C. Temporal Lobe D. Occipital Lobe E. Cerebellum F. Brain Stem The auditory cortex is found in the:
A. Cerebrospinal fluid; external pressure B. Cerebrospinal fluid; infection C. Ventricular fluid; external pressure D. Blood; infection and external pressure The fluid found in the brain's cavities is called ______; this principally protects the brain from ______.
A. Meninges B. Bone C. Gray matter D. White matter E. Blood-brain barrier The _________________ serves as a protective filter that regulates the entrance of certain substances into the brain from the bloodstream.
A. coordination of complex muscular movements B. coordination of endocrine and nervous responses C. control of digestion, circulation, and breathing movements D. center of consciousness What is the primary function of the cerebellum?.
A. Cerebrum B. Cerebellum C. Spinal cord D. Medulla Oblongata You just finished running and your heart rate is fast as is your breathing. The part of the brain controlling basic body functions such as heart rate and blood pressure is the _______.
A. connection between speech and hearing B. motor coordination C. control of many of the endocrine glands D. integration and relay of information The thalamus is responsible for which of the following functions?
A. intelligence and memory B. reflex actions and communication between the brain and spinal nerves C. controlling muscle activity and maintaining balance D. speech, smell, taste, hearing and vision The primary functions of the spinal cord involve __________.