The Eye Blink and Workload Considerations

Abstract

Two parameters of the eye blink, blink r~te and blink du~atio~, were us~d to.ass~ss workload in two independent operational studt es , Both s tud i es f nvol ved h1~h f i del i ty strategic bomber mission simulations. The first study was an extended. wart tme m1SS10n where workload was evaluated during mission segments. The seco~d study l~volved shorter, discrete training missions where task difficulty was systemat1callJ: man ipul ated •.~o~h studies produced complementary results. Results. show t,hat: (1) bl i nk ra~e~s s i qnif icantly affected by task demands; (2) blink rate 1~sens1t1ve to~ask modal1ty, !3) bl1nk duration is significantly affected by task modali ty and comp l exi ty ; and (4) bl i nk duration is a sensitive index of time on task effects.These data support the use of eye blink measurement in "noisy" complex environments as both a feasible and valuable assessment technique.

Using eye movements to measure intrinsic, extraneous, and germane load in a multimedia learning environment.

“…Again, this result seems to indicate further context-dependence of the sensitivity of saccade lengths to cognitive load subtype. blink rate (with more blinks per minute made for the redundant condition than for the nonredundant condition). This result does not seem consistent with previous studies, which have shown a lower blink rate when learners process more difficult or complicated material (Brookings et al, 1996; Stern & Skelly, 1984; Wilson, 2002). We do not have a clear explanation for this effect, as there does not seem to be any literature comparing blink rates made between processing pictorial and textual information.…”

“…Previous studies have measured cognitive load using pupillometry (Ahern & Beatty, 1979; Beatty, 1982; Beatty & Lucero-Wagoner, 2000; Granholm, Asarnow, Sarkin, & Dykes, 1996; Hess & Polt, 1964; Kahneman & Beatty, 1966; Van Gerven, Paas, Van Merriënboer, & Schmidt, 2004), blinks (Brookings, Wilson, & Swain, 1996; Stern & Skelly, 1984; Wilson, 2002), fixation durations (Carroll, Young, & Guertin, 1992; Nuthmann & Henderson, 2012; Rayner, 1998; Underwood, Jebbett, & Roberts, 2004), and saccade lengths (Chen et al, 2011; Loschky et al, 2014; Reimer, Mehler, Wang, & Coughlin, 2012). These eye movement parameters have been used to measure cognitive load in reading (Rayner & Duffy, 1986), mathematics (Marshall, 2002, 2007), arithmetic (Ahern & Beatty, 1979; Hess & Polt, 1964; Kahneman & Beatty, 1966), simulation tasks (Brookings et al, 1996; Stern & Skelly, 1984; Wilson, 2002), visual scene long-term memory tasks (Loschky et al, 2014), and short-term memory (STM) tasks (Granholm et al, 1996). These studies manipulated cognitive load by changing, for example, the familiarity of materials (Rayner & Duffy, 1986), the difficulty/complexity of materials (Ahern & Beatty, 1979; Beatty, 1982; Beatty & Lucero-Wagoner, 2000; Brookings et al, 1996; Carroll et al, 1992; Chen et al, 2011; Di Stasi et al, 2010; Granholm et al, 1996; Hess & Polt, 1964; Kahneman & Beatty, 1966; Marshall, 2002, 2007; Reimer et al, 2012; Stern & Skelly, 1984; Underwood et al, 2004; Van Gerven et al, 2004; Wilson, 2002), and the difficulty level of concurrent tasks such as the N-back task (Loschky et al, 2014).…”

Eye-blinks in choice response tasks uncover hidden aspects of information processing

“…When considering eye blink behavior in cognitive tasks, one might assume that blinks might be inhibited as long as visual information is expected or occur at a time point that represents a meaningful moment in information processing (Stern and Skelly, 1984[ 45 ]; Stern et al, 1984[ 46 ]). Blink inhibition should avoid the missing of relevant signals (Holland and Tarlow, 1972[ 23 ], 1975[ 24 ]; Pivik and Dykman, 2004[ 40 ]).…”

“…As blinking interrupts visual perception for about 250 ms (Kennard and Glaser, 1964[ 29 ]), it is plausible to time blinks whenever such an interruption is less disturbing, and when the risk to miss important information is minimized (Baumstimler and Parrot, 1971[ 4 ]; Stern and Skelly, 1984[ 45 ]). This is not only because the eyelids are simply blocking visual input, but are also affected by a neural mechanism inhibiting processing of visual information (Volkmann et al, 1980[ 53 ]; Volkmann et al, 1982[ 52 ]).…”

Voluntary eyeblinks disrupt iconic memory

“…In an attempt to minimize the probability of missing important information, people reduce their rate of blinking during a visually demanding task (Baumstimler & Parrot, 1971;Drew, 1951;Kennard & Glaser, 1964;Stern & Skelly, 1984). Blinks can also reflect the cognitive demands of a task, irrespective of its visual demands; people blink less often when engaged in a task that taxes cognitive resources (Stern, Walrath, & Goldstein, 1984).…”