September 24 - Cerebral Hemispheres.docx

6 Pages
143 Views
Unlock Document

Department
Anatomy and Cell Biology
Course
Anatomy and Cell Biology 3319
Professor
guestlecture
Semester
Fall

Description
September 24, 2013 Cerebral Hemispheres Pp. 394-403, 405 - Know the names and locations of the major sulci, fissures; and the name, location and border of the lobes of the cerebral cortex - Know the names, locations and function of the motor, sensory and association areas of the cerebral cortex - Brainpower - Right brain vs. Left brain - Higher order processing - Evolutionary advantage - Sensory processing - Creativity - Understanding - Language The Cerebrum - Made of 2 cerebral hemispheres - 83% of total brain mass - Cover the diencephalon and the rostral brain stem - Cerebral cortex (gray matter) o Superficial layer of cortex containing neuron cell bodies - Cerebral white matter o Deep layer containing fibers which connect cell bodies to each other and other areas o Myelination is responsible for the white color - Deep gray matter o Basal ganglia: deep collection of neuronal cell bodies - Overall Function of cerebrum: o Sensory reception and processing o Motor output and processing o Association areas to process complex interactions between brain areas  Perception and interpretation o Cognitive function including decision making (not fully developed until adolescence) - Fissures separate the major portions of the brain (huge indents) – deep sulci o Transverse cerebral fissure: separates the cerebral hemispheres from the cerebellum o Longitudinal fissure: separates the right and left cerebral hemispheres - Sulci: shallow grooves on the surface of the cerebral hemispheres that separate the lobes (separate gyri) o Central sulcus: separates the frontal lobe from the parietal lobe (uninterrupted line to temporal lobe) o Parieto-occipital sulcus: separates occipital lobe from parietal lobe o Lateral/Sylvian sulcus: separates temporal lobe from parietal and frontal lobes (so deep that it’s actually a fissure) o Precentral sulcus: anterior to precentral gyrus o Postcentral sulcus: posterior to postcentral gyrus - Gyri: twisted ridges (raised parts) o Precentral gyrus (anteriorly – primary motor cortex) and postcentral gyrus (posteriorly – primary sensory cortex) border the central sulcus - Lobes within cerebral hemisphere: o Frontal lobe: cognition and motor control o Parietal lobe: somatosensory processing o Occipital lobe: visual areas o Temporal lobe: auditory areas o Insular lobe: visceral (feeling full) and vestibular sensory areas  Buried deep within lateral sulcus/fissure; covered by parts of frontal, parietal and temporal lobes The Cerebral Cortex - Home of the “conscious mind” - Sensory areas: allow conscious awareness of sensation - Association areas: integrate diverse information to enable purposeful action o Unimodal o Take raw, basic sensory features and ascribe meaning to them o Ex, loud, same pitch, equal timing  AN ALARM - Motor areas: control voluntary motor functions - Primary sensory cortex: sensory area for each major sense o Sensory association areas: area in each primary sensory cortex that processes the sensory information o Multimodal association areas: receives and integrates input from multiple regions of the cerebral cortex o Motor cortex: region that plans and initiates voluntary motor functions - Example: o Sensory information is received by the primary sensory cortex, and the arrival of this information results in awareness of the sensation o The information is relayed to the sensory association area that gives a meaning to the sensory input o The multimodal association areas receive input in parallel from multiple sensory association areas, integrating all of the sensory input to create a complete understanding of the sensory information. These regions also integrate sensory input with past experience and develop a motor response o The motor plan is enacted by the motor cortex Sensory Areas - Conscious awareness of sensation occur in parts of the parietal, temporal and occipital lobes - There is a distinct primary sensory cortex for each of the major senses: o General somatic senses, special senses of vision, hearing, balance, olfaction and taste - Each sense also has an association area adjacent to its primary sensory area 1) Somatosensory areas - Primary somatosensory cortex: primary sensory cortex that receives information from the general somatic senses - Located along the postcentral gyrus of the parietal lobe - Touch, pressure, vibration, pain and temperature from skin and proprioception from muscles and joints - Sensory info. is picked up by sensory receptors in periphery of body and relayed through spinal cord, brain stem and thalamus to primary somatosensory cortex - There, cortical neurons process info. and identify area of the body being stimulated  spatial discrimination - Somatotopy: body mapping; each region of the cortex receives sensory stimuli from a specific area of the body - Sensory homunculus (little man) can be constructed for the postcentral gyrus - Lips and fingertips are our most sensitive body parts - Contralateral projection: the right cerebral hemisphere receives its sensory inp
More Less

Related notes for Anatomy and Cell Biology 3319

Log In


OR

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


OR

By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.


Submit