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Structures involved in MCA stroke

1.Paralysis of the contralateral face, arm, and leg and sensory impairment over the same area (pinprick, cotton touch, vibration, position, two-point discrimination, stereognosis, tactile localization, barognosis, cutaneographia -Somatic motor area for face and arm and the fibers descending from the leg area to enter the corona radiata and corresponding somatic sensory system
2.Motor aphasia: Motor speech area of the dominant hemisphere

3.Conduction aphasia: Central speech area (parietal operculum)

Apractagnosia of the nondominant hemisphere, anosognosia, hemiasomatognosia
4.Loss of topographic memory is usually due to a nondominant lesion, occasionally to a dominant one
5.Homonymous hemianopia (often homonymous inferior quadrantanopia): Optic radiation deep to second temporal convolution
6.Paralysis of conjugate gaze to the opposite side: Frontal contraversive eye field or projecting fibers
7.Nondominant parietal lobe (area corresponding to speech area in dominant hemisphere) involvement produce 

  • Unilateral neglect
  • Agnosia for the left half of external space
  • Dressing apraxia
  • Constructional apraxia,
  • Distortion of visual coordinates
  • Inaccurate localization in the half field
  • Impaired ability to judge distance
  • Upside-down reading, visual illusions (e.g., it may appear that another person walks through a table)
8.Central, suprasylvian speech area and parietooccipital cortex of the dominant hemisphere produce the following defects
  • Central aphasia
  • Word deafness
  • Anomia
  • Jargon speech
  • Sensory agraphia
  • Acalculia, alexia, finger agnosia, right-left confusion ( Gerstmann syndrome)