Also known as hemispatial visual inattention and relative hemianopia. The term visual inattention is indebted to the Latin words in (not) and attentio (attention, notice). It is used to denote a failure to detect a visual stimulus presented in one field of vision, while a rival stimulus is simultaneously presented to the opposite field of vision. The Austrian psychiatrist and neurologist Gabriel Anton (1858-1933) is commonly credited with describing the condition for the first time in 1899. The neurophysiological correlates of visual inattention are only partly known. The condition has been described mainly in individuals with parietal lesions due to infarction, but it also occurs in individuals without any demonstrable parietal lesions. Visual inattention due to a progressive parietal lesion may develop into * hemianopia. In clinical practice it may be somewhat of a challenge to distinguish between the two conditions. The notion of visual inattention should not be confused with * inattentional blindness.
References
Anton, G. (1899). Ueber die Selbstwahrnehmung der Herderkrankungen des Gehirns durch den Kranken bei Rindenblindheit und Rindentaubheit. Archiv für Psychiatrie und Nervenkrankheiten, 32, 86-127.
Critchley, M. (1953). The parietal lobes. London: Edward Arnold & Co.
Kooistra, C.A., Heilman, K.M. (1989). Hemispatial visual inattention masquerading as hemi-anopia. Neurology, 39, 1125-1127.
Dictionary of Hallucinations. J.D. Blom. 2010.