 Consumption of dark chocolate has been associated with improved blood flow, cardiovascular function, slowing of degenerative aging processes, as well as enhanced mood and cognitive performance. Dark chocolate is rich in cocoa flavanols which have both antioxidant effects to prevent and impede degenerative disease and as well as more immediate effects on local and cerebral blood flow. One study demonstrated an improvement in contrast sensitivity CS which is the visual ability to detect low contrast targets. Hence dark chocolate may enhance vision during critical task performance in military and law enforcement settings as well as every-day tasks such as driving. Whereas it is assumed that visual enhancements from dark chocolate derive from increased cerebral andor retinal blood flow, direct measurements are lacking. Prior research demonstrated that hands free phone communication verbal distraction can delay reaction time and impair CS. Hence in this study our purpose is to determine if acute consumption of dark chocolate impacts: CS and reaction time with and without verbal distraction, measures of high and low contrast vision as well as color vision, and bjective electrophysiological measures of retinal, optic nerve and cortical function. In prior studies of acute effects of dark chocolate on cognition and CS, the dark chocolate was consumed 90-120 minutes prior to testing. In this study the investigators are using a somewhat larger dose and beginning electrophysiological testing after consumption with color and CS testing approximately 1 hour and 30 minutes afterconsumption. The investigators believe this will capture possible more immediate blood flow changes in retina and cortex based on electrophysiological measures and CS and cognitive changes later in the session. 