Major Brain Regions & Landmarks Cerebrum Cerebrum performs higher mental functions Neural cortex cerebral cortex Neural cortex (gray matter) covered by cerebral cortex Gyri sulci fissures Gyri vs. sulci vs. fissures Cerebellum Cerebellum adjusts movements, balance, etc. Diencephalon thalamus hypothalamus pituitary gland Diencephalon composed of thalamus, hypothalamus & pituitary gland Links cerebrum to brain stem; processes sensory info
Brain stem Brain stem relays info to or from cerebrum or cerebellum midbrain pons medulla oblongata Includes midbrain, pons & medulla oblongata Ventricles of the Brain Lateral ventricles third ventricle fourth ventriclecerebral aqueduct Lateral ventricles vs. third ventricle vs. fourth ventricle; cerebral aqueduct Ventricles filled with CSF
The Cranial Meninges Dura mater arachoid materpia mater Dura mater (outer & inner layers), arachoid mater, pia mater Cerebrospinal Fluid (CSF) Surrounds & bathes CNS surfaces Cushionssupportsnourishes Cushions, supports, nourishes CNS Choroid plexus Choroid plexus in ventricles generate & circulate CSF
Blood Supply to Brain CVA Blood entering cranial cavity compresses & distorts brain tissue (ex: CVA) Blood-brain barrier Blood-brain barrier isolates CNS neural tissue Only CO 2, O 2 & lipid-soluble compounds freely diffuse into brain & spinal cord Blood-CSF barrier Blood-CSF barrier isolates CSF Entry of substances highly controlled by both barriers
Connects brain & spinal cord; coordinates reflexes & visceral functions Medulla oblongata nuclei groups Control visceral activities cardiovascular center respiratory rhythmicity center Control visceral activities (cardiovascular center & respiratory rhythmicity center) Cranial nerves Cranial nerves (motor commands to pharynx, neck & back, visceral organs) Relay stations Relay stations (pass somatic sensory info to CNS)
Links cerebellum with midbrain, diencephalon, cerebrum, & spinal cord Four components Cranial nerves Cranial nerves (jaw muscles, face, eye muscles) Control respiration apneustic pneumotaxic centers Control respiration (apneustic & pneumotaxic centers modify activity of medulla oblongata) Relay info sent to or from cerebellum Ascending, descending & transverse tracts Ascending, descending & transverse tracts (interconnect to CNS)
Major functions Adjust postural muscles Adjust postural muscles (maintain balance & equilibrium) Program movements Program movements (refine learned movements) Receives proprioceptive info from spinal cord; monitors info received by brain Cerebellar peduncles Cerebellar peduncles link cerebellum to other parts of the brain
Processes visual & auditory sensations Issues subconscious motor commands reticular activating system (RAS) Contains the reticular activating system (RAS) Stimulation causes alertness
Epithalamus pineal gland Epithalamus contains pineal gland The Thalamus Filters & relays sensory info to cerebral cortex through 5 nuclei groups limbic system Contains limbic system, awareness of emotions, sensory info
The Hypothalamus Functions Regulates pons & medulla oblongata Coordinate neural & endocrine activities Produce emotions Regulate body temperature Control circadian rhythms
The Cerebral Cortex Longitudinal fissure Longitudinal fissure separates the cerebral hemispheres frontalparietaltemporaloccipital Lobes: frontal, parietal, temporal, occipital White Matter of Cerebrum Interior of cerebrum mostly white matter Commissural fibers corpus callosum Commissural fibers connect the hemispheres at the corpus callosum
Motor & Sensory Areas of the Cortex Know general functions/purposes of each lobe (Table 14-8, pg 472; Figure 14-15, pg 473) Association areas Association areas interpret incoming data & coordinate a response Integrative centers Integrative centers perform complex processes hemispheric lateralization Each hemisphere is responsible for specific functions (hemispheric lateralization)