Running head: CONTENT AND EYE BLINKS 1 Reading Content and Eye Blinks Elisabeth Sepulveda St. Olaf College Author Note: This lab was conducted on November 2, 2014, at St. Olaf College, as part of Research Methods in Psychology with help from Professor Charles Huff and Teacher Assistant Jenna Harder. I can be reached at [email protected] CONTENT AND EYE BLINKS 2 Abstract Eye movement has long been considered indicative of attention. In the following study, we sought to assess the impact of both hard and easy reading material upon eye blinks, in order to discern whether meaningful conclusions regarding attention could be inferred. Our results were only marginally significant, however the identified confounds lead us to believe that future, controlled, iterations of the study could lead towards meaningful results in reading, attention, and ultimately, learning. CONTENT AND EYE BLINKS 3 . Effect of Attention on Eye-Blink Response The relationship between eye blinks and attention is a long-investigated phenomenon in the literature. Scientists have found that assessing eye blinks provides insight into cognitive processes such as the perceptual span, preview benefit, eye movement control, and models of eye movement (Rayner, 2009). As a result, establishing systematic methods for collecting meaningful data based on eye movement has become a valuable focus in research efforts. Just and Carpenter’s classic study, which seeks to find a correlation between reading comprehension and eye movement, sets the foundation for our study through establishing an eye-blink analysis model for assessing attention (1980). Orchard and Stern’s usage of EOG eye movement recordings in relation to difficulty of reading material, extends this research structure into a more detailed model, creating the basis for our methodology (1991). Additionally, their distinction between classically-conditioned Reflex blinks, consciously-controlled Voluntary blinks, and environmentally-responsive Endogenous blinks, introduce relevant confounding variables to consider when assessing blink-response to reading material. In our study, we sought to assess the influence of reading material—whether easy or difficult—on patterns of attention, as manifested in number of eye blinks. Data was collected using an Electrooculogram in order to quantitatively measure response to easy and difficult reading material as related to baseline blinks. We hypothesized that difficulty of the reading material modulates blinkresponse, with easy material eliciting less blinks, and difficult material eliciting more. Method Participants Participants in this study were all students in the Research Methods in Psychology Lab B CONTENT AND EYE BLINKS 4 section. Students in the lab include both domestic and international students from both genders, all within the ages of 18-24 years. Materials Materials used in this study were a BioMac MP36 Workstation, Alcohol-acetone Prep Pads, Non-Latex gloves, Biopac Lesson 10 EOG 1, Biopac Electrode Lead Set (SS2L-2 Sets), Disposable Electrodes, a computer, and SPSS for data analysis. A reading excerpt from the “Three Little Pigs” and an excerpt from Kant’s “Critique of Pure Reason” were included for the “Easy” and “Hard” reading materials. Procedure The study was designed to measure the impact of reading material on number of eye blinks, with number of blinks in easy and difficult reading categories contrasted against a baseline category for each student in the lab. In order to create this effect, students were first introduced to the experimental design by Professor Chuck Huff, who described the reading material categorization and process of measuring blinks to the class. Students then chose a lab partner and dispersed towards different Electrooulogram stations throughout the lab. Once students arrived at the station, the BioPac MP36 units were checked to make sure they were off before electrode leads were plugged into the MP36, with Horizontal as channel 1 and Vertical as channel 2. The MP36 machine was then turned on, latex gloves were put on, and for each pair, student A cleaned student B’s face with Alcohol Prep Pads, before placing 6 electrodes on student B’s face— two directly over each eye, one on the outside corner of each eye, one in the middle of the forehead, and one under the right eye. The horizontal electrode lead set from channel 1 was attached to electrodes next to right eye, left eye, and above the left eye. The vertical electrode lead set from channel 2 was attached to electrodes above and below the right eye as well as in the middle of the forehead. Masking CONTENT AND EYE BLINKS 5 tape was used to secure wires in place. Once electrodes and lead sets were attached, student A opened the BIOPAC student lab program, selected “Lesson 10—Electrooculogram”, and clicked on “Calibrate”. Student B, facing the computer, then looked from extreme left to extreme right and back to center 4 times, then extreme top to extreme bottom and back to center 4 times to calibrate the program. Following calibration, student A clicked “Record” on the program, and held a pen approximately 10 inches in front of student B, while moving the pen laterally 10 inches and back to the center over the course of 3 seconds, repeating this motion for up and down eye movements as well. Once calibration was in place, student A held a piece of blank paper approximately 10 inches in front of student B, and recorded student B’s eye movement over the course of 60 seconds. Blinks were counted, and data was recorded under the category of “Baseline”. Next, student A held “The Three Little Pigs” in front of student B, and recorded eye movements for another 60 seconds, while student B read. Number of eye-blinks were counted and entered under the “Easy” category. Finally, student A held Kant’s “Critique of Pure Reason” excerpt in front of student B, and recorded eye movements for a final 60 seconds. Number of eye-blinks were counted and entered under the “Hard” category. Student researchers then switched places, to ensure that data was collected for each lab member, and results were compiled into a chart for statistical analysis through SPSS, based on the total collection of class data. Results On average, the participants blinked -3.1667 times less than their baseline number of blinks during the easy reading (SD = 10.347), and 2.9167 times more during the hard reading (SD = 14.7923). Though the adjusted blink rate for the hard reading is larger than the adjusted easy rate, it is not CONTENT AND EYE BLINKS 6 significantly larger (t (11 ) = -1.703, p = .117). Discussion Because participants blinked only slightly less than their baseline during the easy reading, and only slightly more than their baseline during the hard reading, no strong conclusions regarding attention can be inferred. While the adjusted blink rate for the hard reading produced stronger results, it was not by a significant margin, and therefore only slightly supports the hypothesis. Of note is the fact that data ranged widely based on individual participants—from Baseline to Easy to Hard—and as such, there is a great degree of variance between individual results. As a result, the averages used for statistical analysis leave room for additional analysis between participants. For example, unlike the studies read for context in the introduction, intentional blinks were not measured against unintentional blinks—all blinks were included in the data. Because participants were also simultaneously researching, their prior knowledge about the study, along with their awareness of the ways in which their eye movement was being assessed, could have influenced their blinks in any one of the categories, ultimately skewing the data. Additionally, some students wore contact lenses during the study while others didn’t—a factor proven to correlate with blinking, while unrelated to the reading attentiveness we were measuring for. While the results of the study were only marginally significant, with consideration given to potential confounds affecting blinking, meaningful results could, potentially, be discovered in later iterations of the study. If eye-blinks are, indeed, significantly correlated with reading comprehension, an understanding of input and comprehension in learning can be furthered, through using eye blinks as an indicator of attention to material. While the jump to meaningful conclusions appears large, the potential for insight into learning processes through further study of this phenomenon is a promising CONTENT AND EYE BLINKS 7 reward. References Goldstein, R., Bauer, L. O., & Stern, J. A. (1992). Effect of task difficulty and interstimulus interval on blink parameters. International Journal of Psychophysiology, 13, 111-117. Just, M. A., & Carpenter, P. A. (1980). A theory of reading: From eye fixations to comprehension. Psychological Review, 87(4), 329-354. Loebech, J, & Thorsheim, H, (2010). Eye Blinks and Eye Movements in Cognition. Unpublished manuscript, Department of Psychology, St. Olaf College, Northfield, MN. USA. Orchard, L. N. & Stern, J. A. (1991). Blinks as an index of cognitive activity during reading. Integrative Physiological and Behavioral Science, 26(2), 108-116. Rayner, K. (2009). Eye movements and attention in reading, scene perception, and visual search. Quarterly Journal of Experimental Psychology, 62(8), 1457-1506.