This study examined the incidence of neckwear tightness among a group
of 94 white-collar working men and the effect of a tight business-shirt collar
and tie on the visual performance of 22 male subjects. Of the white-collar
men measured, 67% were found to be wearing neckwear that was tighter than
their neck circumference. The visual discrimination of the 22 subjects was
evaluated using a critical flicker frequency (CFF) test. Results of the CFF
test indicated that tight neckwear significantly decreased the visual
performance of the subjects and that visual performance did not improve
immediately when tight neckwear was removed.
— Langan, L.M. and Watkins, S.M. “Pressure of Menswear on the
Neck in Relation to Visual Performance.” Human Factors 29,
#1 (Feb. 1987), pp. 67-71.