Visual Field Studies After Temporal Lobectomy for Epilepsy

Although human temporal cortex is known to be important for short- and long-term memory, its role in visual perception is not well understood. In this study, we compared the performance of three patients with unilateral temporal lobectomies to that of normal controls on both fisimplefl and ficomplexfl visual discriminations that did not involve explicit memory components. Two types of complex tasks were tested that involved discriminations secondary to texture segmentation. These were contrasted with simple discriminations using luminance-defined stimuli. Patients showed impaired thresholds only on tasks involving texture segmentation, performing as well as controls when the targets were defined by luminance rather than texture. The minimum stimulus presentation times for threshold performance were also measured for all tasks and found to be elevated in temporal lobectomy patients relative to controls. Although the magnitude of the deficits observed was substantial, loss was equivalent in ipsi- and contra-lesional regions of the visual field. Additional control experiments showed that the patients' perceptual deficits were not due, even in part, to disturbances of basic visual capacities such as acuity and contrast sensitivity. Our results indicate that temporal lobe damage disrupts complex, but not simple, visual discriminations throughout the visual field.

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Choice of test Objects in Visual Field Studies*

American Journal of Ophthalmology ◽

10.1016/0002-9394(52)90011-1 ◽

1952 ◽

Vol 35 (3) ◽

pp. 381-393 ◽

Cited By ~ 4

Author(s):

Max Chamlin ◽

Leo M. Davidoff

Keyword(s):

Visual Field ◽

Field Studies ◽

Test Objects

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VISUAL FIELD DEFECTS AFTER TEMPORAL LOBECTOMY

Acta Ophthalmologica ◽

10.1111/j.1755-3768.1957.tb05407.x ◽

2009 ◽

Vol 35 (3) ◽

pp. 210-216 ◽

Cited By ~ 11

Author(s):

Ǎke Björk ◽

Eric Kugelberg

Keyword(s):

Visual Field ◽

Temporal Lobectomy ◽

Visual Field Defects ◽

Field Defects

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Use of Quinclorac Plus 2,4-D for Controlling Field Bindweed (Convolvulus arvensis) in Fallow

Weed Technology ◽

10.1017/s0890037x00042147 ◽

1999 ◽

Vol 13 (4) ◽

pp. 731-736 ◽

Cited By ~ 4

Author(s):

Stephen F. Enloe ◽

Philip Westra ◽

Scott J. Nissen ◽

Stephen D. Miller ◽

Phillip W. Stahlman

Keyword(s):

Triticum Aestivum ◽

Visual Field ◽

Count Data ◽

Late Summer ◽

Field Studies ◽

Strong Correlations ◽

Convolvulus Arvensis ◽

Fallow Period ◽

Field Bindweed ◽

Better Than

Field studies were conducted in Colorado, Kansas, and Wyoming to compare the use of quinclorac plus 2,4-D with picloram plus 2,4-D, dicamba plus 2,4-D, a glyphosate plus 2,4-D premix, and 2,4-D alone for control of field bindweed (Convolvulus arvensis) in a winter wheat (Triticum aestivum)-fallow rotation. Treatments were applied in late summer or fall each year for two, three, or four consecutive years at the beginning and end of each fallow period. Evaluations were taken 10 to 12 mo after treatment each year. Quinclorac plus 2,4-D and picloram plus 2,4-D consistently performed as well as or better than 2,4-D, dicamba plus 2,4-D, and glyphosate plus 2,4-D. Wheat yields increased when field bindweed was controlled during the fallow period. Strong correlations (r> −0.85) were obtained among visual field bindweed evaluation, biomass, and stand count data.

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