Date of Award
Master of Science in Chemical Sciences (MSCB)
Kimberly Linenberger Cortes
Adriane B. Randolph
The areas of chemistry and biochemistry commonly use external representations to enhance learning for students. The use of schematics and representations for illustrating metabolic pathways is a familiar image in most biochemistry textbooks. These external representations can be the key to student understanding. To date, there has not been any previous research specifically focused on the areas of interest that are predominant for an individual viewing a metabolic pathway commonly found in a biochemistry textbook. Therefore, this thesis study set out to 1) investigate what individuals look at in a metabolic pathway based on their level of expertise in metabolism and 2) to look at areas of brain activation during the time an individual is viewing a metabolic pathway based on their level of expertise in metabolism. This was a phenomenological study; however, multiple theoretical frameworks guided the development, collection, and analysis of the data in this study.
The method used to collect the data included manually co-registered systems of eye-tracking and electroencephalograph (EEG) followed by separate analysis. The experiment was conducted using 45 participants with varying levels of expertise in biochemistry. Through a post-survey, the participants were found to have different levels of familiarity with the metabolic pathways used for the stimulus presentation. This research concentrated on determining what part of the image the participants focused on and tracked the path that participants took while viewing metabolic pathway representations. This was accomplished through the use of an eye-tracking system that mapped the movement of the participants' eyes while engaged with the image. The participants consisted of novices with little to no exposure to metabolic pathways, amateurs currently taking a biochemistry class that was discussing metabolism, and experts who presently teach biochemistry. Through scanpath data, the differences in how the groups read a glycolysis pathway and the inosine monophosphate pathway (IMP) were determined.
Areas of activation in the brain while viewing the images were identified through analysis of the EEG data. It was determined that when presented with a familiar metabolic pathway the amateur group was more similar to the expert group with the number of vertical translations, amount of transitions between areas of interest, and fixation durations. For an unfamiliar pathway, the amateur group was more like the novice group with fewer transitions and a lower amount of vertical translations. It was also determined that the activation in the brain between the novice and amateur groups was similar, with the highest level of activation in the occipital lobe area. In contrast, the expert group had different patterns of brain activation showing more activity in the frontal lobe. The second part of the study showed there was little difference in the way an amateur group with some exposure to metabolic pathways read and processed metabolic pathways containing a targeted question as compared to a novice group with little to no exposure to metabolic pathways. The expert group had different patterns of brain activation compared to the novice and amateur groups. This study will set the baseline to ultimately determine how to best present and promote visual literacy in classes which utilize external representations for higher level learning content.