PSIO 5th Edition Lecture 27 Outline of Last Lecture Brain Outline of Current Lecture I II III IV Brain Structure Sensory Areas of the Brain Aphasia Cerebral White Matter Current Lecture Brain Structures and Functions I Objectives 1 Describe the location and function of the specific functional areas of the cortex as described in lecture 2 Describe the general location and function of the basal nuclei 3 Describe the location and function of cerebral white matter 4 Describe hemispheric lateralization Four Major Parts of the Brain 1 Cerebrum 2 Cerebellum 3 Diencephalon Thalamus Hypothalamus Epithalamus 4 Brain stem Midbrain Pons Medulla Oblongata Cerebrum Functional areas of the cerebral cortex gray matter 1 Sensory areas 2 Motor areas 3 Association areas Primary Somatosensory Area grey matter Primary Motor Area precentral gyrus Broca s Speech Area Primary Auditory Area Brodmann s Area Numbered Regions of Cortical tissue Primary Motor Area Location precentral gyrus in frontal lobe Function voluntary activation of skeletal muscles Premotor Area motor association area Location anterior to primary motor area in the frontal lobe Function communicates with primary motor area and thalamus to coordinate complex learned movements Primary Somatosensory Area Location Postcentral gyrus in parietal lobe Function Receives sensory impulses from sensory receptors responding to touch temperature and proprioception Sensory and motor inputs and outputs of the cerebral cortex are not equal for all parts of the body Entire body can be represented spatially on the primary motor and sensory areas of the cerebral cortex Primary Visual Area Location medial portion of occipital lobe Function nervous signals traveling along the optic nerve provide information about color shape and movement of visual stimuli Visual Association Area Location occipital lobe anterior to the primary visual area Function receives sensory impulses from the primary visual area for recognition of visual stimuli visual memory Primary Auditory Area Location superior portion of temporal lobe Function receives impulses arising from the vestibulocochlear nerve which provide information of the basic characteristics of sound pitch rhythm loudness Auditory Association Area Location temporal lobe inferior and posterior to the primary auditory area typically found on left temporal lobe only Function interpretation and recognition of sound determines if sound is speck music or noise Auditory Association Area Wernike s Area Location temporal lobe posterior to primary auditory area on left lobe Function interprets the meaning of speech translates words to thoughts Motor Speech Area Broca s Area Location frontal lobe usually left side Function controls the activity of muscles of the vocal cords to facilitate speech Aphasia Acquired communication disorder that impairs a person s ability to process language but does not affect intelligence Most common cause is stroke Broca s Aphasia non fluent Wernicke s Aphasia fluent Basal Nuclei The basal nuclei are centers of cell bodies deep in the cortex gray matter help initiate and terminate movements suppress unwanted movements regulate muscle tone control subconscious contractions of skeletal muscles Cerebral White Matter Myelinated axons that are bound into large tracts White matter is responsible for communication between cerebral areas and between cerebral areas and other parts of brain Cerebral White Matter Association tracts contain axons that conduct nerve impulses between gyri in the same hemisphere Commissural tracts conduct nerve impulses between corresponding gyri from one hemisphere to another Projection tracts convey impulses to lower parts of the CNS The Corpus Callosum is one of the three important groups of commissural tracts it is a thick band of axons that connects corresponding areas of the two hemispheres
View Full Document
Unlocking...