lobes n functions of cerebrum

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    LOBES & FUNCTIONSOF CEREBRUM

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    Also known as cerebral cortex, a Latin word

    for brain.

    It is the largest part of human brain. Associated with higher brain function.

    Located in the anterior portion of the

    forebrain.

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    Parts of the brain can be descriptively dividedinto:

    Two hemispheres

    Four lobes(section)

    1)DIVISION ACCORDINGTO HEMISPHERES

    Cerebrum is divided into 2 parts:a) Right hemisphere

    b) Left hemisphere

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    Right hemisphere- controls the left side of

    the body.

    Left hemisphere- controls the right side ofthe body.

    Each of these sections are assigned a

    particular task. (eg: right hemispheres ofcerebrum associated with creativity, lefthemispheres of cerebrum associated with

    logical abilities)

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    Cerebrum divided into four sections:

    o Frontal lobe Voluntary motor coordination,

    reason, planning, emotion.o Parietal lobe Responsible for sense of touch or

    perception.

    o Temporal bone Proper functioning of auditory& olfactory (smell senses)

    o Occipital bone Visual or Sight

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    CEREBRUM

    Hemispheres Lobes

    Right

    hemisphereLefthemisphere

    Frontal lobe

    Parietal lobeTemporal lobeOccipital lobe

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    1) LATERAL SULCUS: Separates temporal lobe from parietal & frontallobes

    2) CENTRAL SULCUS: Separates frontal & parietal lobes

    3) PRECENTRAL SULCI: Parallel & infront of central sulci

    4) POSTCENTRAL SULCI: Right behind the central sulci

    5) PARIETO-OCCIPITAL SULCUS: Separates parietal lobe from occipitallobe

    6) PRECENTRAL GYRUS(MOTOR CORTEX): Gyrus between centralsulcus & precentral sulcus

    7) POSTCENTRAL GYRUS(SENSORY CORTEX): Gyrus between centralsulcus & postcentral sulcus

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    (A) Frontal Lobe:- It is a Latin word for forehead. Lies right behind the frontal bone/ forehead. BOUNDARIES: Extends from central sulcus to the

    anterior of brain.

    Functions of frontal lobe:1. voluntary motor activity2. Speaking ability3. Elaboration of thought4. Reasoning, planning & emotion5. Movement6. Problem solving

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    1. MOTOR AREA/CORTEX

    LOCATION: Back portion of frontal lobe, along

    with central sulcus that separates it fromparietal lobe.

    Function :o voluntary control over skeletal muscles

    movement.o In sensory processing, each side of brain

    controls muscles on opposite side of body.

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    In motor cortex it is called as motorhomunculus.

    Represents the amount of control it has invaries parts of body. It is represented upside down in motor

    cortex.

    Indicates the location and amount of motorcontrols devoted to output of each muscles. The proportion depends on how precise and

    complex the motor skill or function is.

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    Function : involved in complex cognitive processes.(eg: behavior,character or intellectual trait, reasoning& judgement)

    C. Brocas Area Also called speech centers Location: bottom of left frontal lobe. Function: -

    Important for specialization of language

    Speaking abilities

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    Situated behind frontal lobe, separated by a

    deep infolding called the central sulcus.

    In Latin word, parietal means wall . Function:

    Primarily responsible for receiving and processingsensory input.

    It has an area called somatosensory cortex.

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    Located in the front portion of parietal lobe.

    Responsible for sensation of touch,pressure,

    heat, cold, & pain. Somesthetic sensation means body feelings

    Sensory inputs travels from PNS to CNSSOMATOSENSORY(higher brain level)

    It is the site for initial cortical processing &perception..Which carries somesthetic input

    & proprioceptive input.

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    It is called the somatosensory homunculus.

    Homunculus means little men

    Body represented upside down.

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    B) Sensory speech area (WERNICKS AREA)

    Situated in the lower part of parietal lobe.

    Function: The place where spoken words are perceived.

    Concerned with language comprehension

    Understanding both spoken & written messages.

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    At the side of head is temporal lobe. Locatedlaterally in each hemishpere.

    Boundaries: Inferior to lateral sulcus & and

    anterior to occipital lobe. Function:

    i. Responsible for proper functioning of auditory (hasauditory area)

    ii. Sound sensation is initially received by temporallobes.

    iii. Acts as olfactory area (smell sensation)iv. Important to maintain equilibrium in the body.

    (balance)

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    LOCATION: Located posteriorly at the back

    of head.

    Contains primary visual cortex Function:

    Initial processing of visual input from eyes.

    Any injury which leads to damage to primary

    visual cortex causes blind vision or loss ofsight.

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