Right side of the screen catches the eye more than the left finds study

By Dr. Ananya Mandal, MDSep 4 2019

A new study from the HSE University researchers Elena Gorbunova and Maria Falikman reveals that when reading off a screen, an individual tends to comprehend the words on the right side of the screen faster than those on the left. The processing speed of the information of the brain also depends on the amount of information presented on the screen explain the researchers. The study titled, “Visual Search for Letters in the Right Versus Left Visual Hemifields,” was published in the journal, Advances in Cognitive Psychology.

Study: Visual Search for Letters in the Right Versus Left Visual Hemifields. Image Credit: Monkey Business Images / Shutterstock

The team of researchers conducted their experiments in the Laboratory for the Cognitive Psychology of Digital Interface Users. There were a series of experiments where the team looked at the speed and accuracy of the word processing when presented to the volunteers on a screen. Both the placement of the words on the screen and their quantity were found to determining factors in speed and accuracy of comprehension.

The researchers explained that cognitive functions of both sides of the brain are different. This means that the left side of the screen sends in the signals to the left field of vision. This reaches the right hemisphere of the brain and similarly an image on the right of the screen is received at the left hemisphere of the brain. They write, “Visual field asymmetries refer to differences in the processing of stimuli presented in different parts of the visual field. There are three types of visual field asymmetries reported in the literature: (a) left/right, (b) temporal/nasal, (c) and upper/lower.”

Experiment 1

In the first experiment the participants were given two letter strings of the same type (these could be words or pictorial clues). The two clues were presented to both the visual fields. The authors write, “In Experiment 1, we studied the visual search for a letter within two letter strings (either words or nonwords) presented simultaneously on the computer screen. Our hypothesis was that we would observe differences in the search between words in the LVF and RVF. We also expected to find a general left-to-right bias (faster search within LVF as compared to RVF) determined by reading direction typical for most European languages, including Slavic ones.”

The participant was first shown a target letter. He or she would have to find this in a string of letters shown to them. The participant was shown a string of letters on either side of the screen at once. They would have to search for the target letter as quickly as possible and press a key on console to indicate that they have located the specified letter. Both visual fields were tested for their speed in identifying the letter by a letter-by-letter search.

In this experiment 22 participants (19 females) between the age of 17 and 28 years and Russian speakers were chosen to participate. They were all right handed and had corrected or normal vision. They participated in the experiment in a dark room 70 cm from the screen with 576 trials write the researchers.

Experiment 2

In this experiment only one letter string was presented either in the right or left side of the screen for fixation. The authors wrote, “In Experiment 2, to test the hypothesis that the involvement of one or both visual hemifields might influence the search mode, we presented one rather than two letter strings on the screen. We expected that the presence of just one letter string in the entire visual field might lead to its focal attentional processing without the contributions of hemispheric asymmetry.” This meant that they presented the reader with two letter strings on either side of the visual field and checked on the speed and accuracy of processing.

In this experiment 19 participants (11 females) between the age of 17 and 35 years and Russian speakers were chosen to participate. They had not participated in the Experiment 1. They were all right handed and had corrected or normal vision.

Experiment 3

In this two non-related letter strings were presented to both the visual fields. The authors wrote, “...in Experiment 3, we tested the possible contribution of lexicality priming (readiness to process a certain type of string) to the participants’ choice of the search mode. In this experiment, we used different types of letter strings in each trial instead of using either two words or two non-words.” The experiment 3 was a modification of the experiment 1.

In this experiment 23 participants (14 females) between the age of 17 and 25 years and Russian speakers were chosen to participate. They had not participated in the Experiment 1. They were all right handed and had corrected or normal vision.

For all the three experiments time to respond to the clues and accuracy of the data seen and recalled was assessed. Results showed that in Experiment 1 there was a letter-by-letter search for the word in the left side of the field including the non word clues presented in the right side of the field. The experiment 1 results revealed that there are different word processing strategies of either side of the brain. This meant that the left brains of the right handed participants could find the target letter faster when the letter was presented to the right side of the screen. When the right brain was so employed in these individuals, the participant was slower in checking each letter by letter.

For experiment 3 the search for the letters was seen in right side of the visual field. If the target letter was hidden in a sequence of letters that were meaningless, the left brain tried to search for the target letter by checking on each letter while the right brain processed the whole set at once and found the target letter faster.

If the total amount of information on the screen was high, the brain chose a different word choosing strategy, the experiments showed. The researchers concluded, “These results demonstrate that presence of stimuli in both one or two hemifields and the readiness to process a certain string type might contribute to the search for a letter within a letter string.”

Study author Elena Gorbunova explained, “When there is a lot of information, that is, when we need to process two words on the left and on the right, our brain begins to save energy and processes the words simultaneously. When there is not enough information, the brain relaxes and processes the information sequentially. Therefore, when placing text on the screen, you need to monitor how much information you are presenting to the user.”

The researchers explained that this study is an important tool for children with dyslexia and other reading and learning disabilities to ensure greater comprehension of the words presented to them on screen. This could also be a valuable tool for developing more successful interfaces for online advertisements, gaming etc. they add.