Investigator Roderick D.K. Watt alerts us to a newly published study about the interaction of Viagra and dim lighting. The study is:
“The Effect of Sildenafil Citrate (Viagra?) on Visual Sensitivity,” Andrew Stockman, Lindsay T. Sharpe, Adnan Tufail, Philip D. Kell, Caterina Ripamonti and Glen Jeffery, Journal of Vision, vol. 7, no. 8, 2007, pp. 1?15. The investigators, at University College London and other institutions in the same city, explain:
“Although Viagra might… be expected to impair visual performance, reports of deficits following its ingestion have so far been largely inconclusive or anecdotal…. We measured temporal acuity (critical fusion frequency) and modulation sensitivity in four subjects before and after the ingestion of a 100-mg dose of Viagra under conditions chosen to isolate the responses of either their short-wavelength-sensitive (S-) cone photoreceptors or their long- and middle-wavelength-sensitive (L- and M-) cones.”
Investigator Watt comments:
The dose of 100 milligrams is more than adequate to get the conventional physiological response, so how did they ignore it as they sat looking at flashing lights? Note also the heroism of the experimenters, who in the grand tradition experimented on themselves… And what did they do when they got home, after a long day’s experimenting in the lab? I think we need a little more methodological clarification. As for the phrase that “AT and GJ were comparatively naive at the start of the experiment” …. Well!
Considering the effects themselves, does the modification of the time response mean that really things don’t actually last longer, they just seem to? Likewise with the improvement in visual persistence mentioned in the discussion… And what about that line at the end, about effects outside the laboratory “under conditions of reduced visibility” — no problem, as I guess few people would dream of taking Viagra and then having low levels of illumination of, say, one candle-power?