Neuro: Functional Areas Flashcards
Site of Motor Area 4
Precentral gyrus and anterior part of paracentral Lobule
Function of motor Area 4
origin to 40% of pyramidal tract (corticospinal and corticonuclear) of opposite half of body
Lesion to Motor Area 4
Contralateral Hemiplegia
Motor area of lower part of lower limb and perineum
Anterior part of paracentral lobule, medial surface of cerebral hemisphere (motor Area 4)
Motor area 4 is the pyramidal Area for All the body except
The eye
Representation of the body in motor Area 4
Inverted upside down
Site of Premotor Area (6)
In front of Motor Area 4
Function of premotor Area (60
- 40% pyramidal tract
- Extrapyramidal tract
- Succesful performance of Acts (by storage of skilled movements learned by experience)
- Inhibition of muscle tone
Lesion to premotor Area 6
- Motor Apraxia
- Instability of posture
- Spasticity of muscles (high muscle tone)
Site of Frontal eye field Area (Area 8)
Posterior part of middle frontal Gyrus
Function of Frontal Eye field Area (8)
- lateral Conjugate eye movement
- Accommodation reflex
Lesion to Frontal Eye field Area (8)
- Loss of Lateral Conjugate eye movement
- Loss of Accommodation
Site of Broca’s Area (Area 44)= Motor speach area
Posterior part of inferior frontal gyrus of dominant hemisphere (commonly left)
Function of Broca’s Area (Area 44)
- Formation of speech by connections with primary motor Areas
- Coordinates movement of larynx, tongue and lips
Lesion to Broca’s Area (Area 44) leads to
Motor Aphasia (patient unable to express his thoughs through speech)
Site of Prefrontal Area (association Area)
remaining part of Lateral surface of frontal lobe
Function of Prefrontal Area (association Area)
Personal Reactions (emotions and behaviour)
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Medial Surface of frontal lobe is responsible for
Emotional behaviour
Lesion to Prefrontal Area (association Area) causes
Personality Changes
Orbital Surface of Frontal Lobe is responsible for
Control of Autonomic Activities
Site of main sensory Area (3,1,2)
Postcentral gyrus and posterior part of paracentral Lobule
Function of main sensory Area (3,1,2)
- Higher centers for general Somatic Sensation Of the opposite half of the body
- Gives 20% pyramidal tract
Lesion to main sensory Area (3,1,2) leads to
Contralateral Hemi-anesthesia
Site of Parietal Association Area
Remaining part of Parietal Lobe, behind postcentral Sulcus
Function of Parietal Association Area
Area where Visual, auditory and Tactile Sensations associate and are given meaning to
Lesion to Parietal Association Area leads to
Astereognosis
Site of Supramarinal Area (Area 40)
Inferior Parietal Lobule
Function of Supramarginal Area (40)
(2nd speech Area of Wernicke) Understands written and spoken language +Sending Speech to broca’s area
Lesion to Supramarginal Area (40) leads to
- Inability to understand Written and spoken words (sensory Aphasia)
Site of Angular Gyrus (Area 39)
Inferior Parietal Lobue
Function of Angular Gyrus (Area 39)
Rest of Speech area of Wernicke (written language)
Lesion to Angular Gyrus (Area 39) leads to
Alexia and Agraphia (inability to read and write)
Site of Auditory sensory Area (41&42)
Middle of Superior Temporal gyrus
Site of Auditory Association area (22)
Rest of superior Temporal Gyrus surrounding the Auditory sensory Area
Function of Auditory Sensory Area (41,42)
Recieves Auditory Radiation from medial Geniculate body (for perception)
Lesion to Auditory Sensory Area (41,42) leads to
Bilateral diminution of Hearing
Function of Auditory Association Area (22)
Knowing meaning of heard sounds
Lesion to Auditory Association Area (22) leads to
Auditory Agnosia
Rest of temporal lobe seems to be concerned with
Memomry mechanism
Site of Visual Sensory Area 17
At lips of postcalcarine sulcu (in both cuneus and ligual gyruses)
Function of Visual Sensory Area 17
Recieves Radiation fibers from lateral geniculate body
Lesion to Visual Sensory Area 17 leads to
ContralLateral hemianopia with macular sparing
Site of Visual Association Area (18,19)
Surrounding Visual sensory area
Function of Visual Association Area (18,19)
Meaning behind images and colour vision
Lesion of Visual Association Area (18,19) leads to
Visual Agnosia and colour blindness
