Brain and Cerebrum

  • Brain

    • A single neuron is capable of transmitting an electrochemical signal

    • It takes many neurons interconnected with each other to act as a control system.

    • The human brain contains. an estimated 86-100 neurons.

    • These neurons share an estimated 100 trillion connections.

  • Regions of The Brain

    • cerebrum

    • cerebellum

    • brain stem

    • Diencephal

  • Surface features: the surface of the cerebrum and cerebellum are folded into.

    • Gyri/ Gyrus: The folding’s that stick out

    • - Sulci/ sulcus: The folding inside (grooves, in between gyri)

  • Cerebrum: Superior view are divided into:

    • Anterior

    • Posterior

    • Left hemisphere

    • Right Hemisphere

  • Cerebral Hemisphere

    • two hemisphere are largely mirror image of each other

    • However, here are functional differences between the two sides Anterior & Posterior

  • Cerebral Matter

    • internally two distinct colors of tissue and identifiable within the cerebrum

    • Gray Matter: dense clusters of neural cell bodies, dendrites, and unmyelinated axons.

    • White Matter: cater of myelinated axon.

  • Gray Matter is located in:

    • Cerebral cortex: our conscious mind

    • cerebral nuclei: subconscious process

  • Ventricles

    • In center of the cerebrum, there are hollow spaces called ventricles

    • in a living person, the ventricles would be filled with cerebrospinal fluid

    • Ventricles are continuous with each other as well as with central canal

  • Protecting the brain

    • Nervous tissue is soft and fragile.

    • We have multiple layers of connective tissue that protect the brain superficial to deep.

    • 1. Scalp

    • 2. peristomium

    • 3. Cranial Bones

    • 4. Dura Matter

    • 5. Arachnoid Matter

    • 6. Pia matter

  • Menaingitis

    • The meninges contains a heavy supply of vascularization

    • meningitis is a condition in which the meninges become inflamed

    • Results in a abnormal amount of pressure on the brain meninges

    • dura matter

    • Arachnoid

    • Dia matter

  • Cerebral Fluid (CFS)

    • CFS is colorless fluid when circulates in ventricles and subarachnoid space

  • CFS Performs Several Functions

    • Buoying to float the brain

    • cushion against excessive movement of the brain

    • circulates nutrients and moves waste from the cns

  • CFS Production

    • CFS is formed by plexus

    • the choroid plexus contains a layer of ependymal cells which filter and alterblood plasma to produce the CFS

  • Blood Brain Barrier

    • Your body suspend energy to produce CFs because it cleaner than blood may contain bacterial or viral particles as well as expenses.

    • ions flu cations which may damage the brain

    • The BBB prevents blood from coming into direct contact with the brain

    • BBB is composed of a continuous endothelial lining of the capillaries of the brain as well as “feet” of nearby astrocytes.

    • Since BBB is composed largely of the plasma membrane-based structure it is mostly lipid

    • That means that lipid soluble chemical can cross the BBB suncas steroid hormones

    • Alcohol

    • nicotine

    • Some atheistic

    • BBB can act as a barrier when prevents non lipid drugs from reaching the brain

    • This can make it difficult to design and deliver medications meant to treat conditions affecting the brain such as Alzheimer’s diseases or certain cancer.

  • Cerebral structures

    • cerebrum'

    • The cerebrum is the location of:

    • conscious throughout process

    • complex intellectual function

  • Corpus Gallo sum

    • The two hemispheres of cerebrum are interconnected by tracts of white matter.

    • The largest tract connecting the two hemispheres is the callosum.

  • Tracts

    • due to the way white matter travels enter the cerebrum each hemisphere. each hemisphere is largely responsible for sensory perceptions and motor control of the opposite side of body.

    • Lateralization of cerebral function:

    • In addition to largely being responsible for opposite side of body. Each hemisphere also tends to feature unique functional area, this results in what is known as lateralization of cerebral function.

  • Lobes of cerebrum

    • Each hemisphere is divided into anatomically and functionally distinct lobes.

    • Parietal Lobe

    • Frontal

    • Insula Lobe

    • occipital lobe

    • temporal lobe

    • Cerebellum

  • Functional Areas

    • The structural areas of the cerebrum can often be assigned to regulating certain functions

    • There are at least 3 different types of functional areas located within the cerebrum:

    • Motor areas: control voluntary motor functions

    • Sensory areas: Provide conscious awareness of sensation.

    • Association Areas: integrate and store information

    • Motor and sensory areas can often be assigned to specific structural regions.

    • Association areas are often dispensed over large area and harder to define.

  • Frontal Lobe

    • Central sulcus

    • Frontal lobe

    • Lateral sulcus

  • Frontal lobe Functional areas

    • Directly anterior to the central sulcus is the precentral gyrus(structural name)

    • the precentral gyrus is the location of the primary motor cortex

  • Motor Homunculus

    • specific regions the primary motor cortex are associated with controlling skeletal muscle

    • The map that illustrates these regions are known as the motor homunculus

    • At the interior inferior edge of the primary motor cortex is the motor speech area

    • Previously called the Bruscas area

    • it controls speech.

    • Anterior to the primary motor cortex and superior to the motor speech area is the frontal eye field.

    • controls voluntary movement of eye.

    • some research group the frontal eye field into the premotor larger premotor cortex

    • the premotor cortex is an association area for controlling learned movements.

  • Prefrontal cortex

    • this where we make decision about how to interact with the world around us.