WORD DURATION AS A FUNCTION OF WORD LENGTH IN RSVP READING

Title WORD DURATION AS A FUNCTION OF WORD LENGTH IN RSVP READING
Author, Co-Author Kathy Aquilante, Dean Yager, Robert A. Morris, Maithreyi Vallabhajosyula
Topic
Year
2002
Day
Saturday
Program Number
Room
Room 2 SP
Affiliation
Abstract PURPOSE: In a previous study we reported that low vision patients with age-related macular degeneration (AMD) read RSVP text faster when word duration varied with word length. In that study readers with normal vision read more slowly in the variable duration condition compared to reading sentences with constant word duration. Low vision readers also slowed down in the condition where the difference in exposure duration between short and long words was greatest. We hypothesize that reading rates slowed when short words appeared too rapidly to be perceived.

METHODS: Participants read English sentences presented with the RSVP method. Word duration during RSVP was varied according to the following formula: Duration*(word length/5) raised to exponents 0.0, 0.25, 0.5, or 1.0 for a given block of trials. For one set of blocks a minimum exposure duration was included. For a 300 wpm base reading rate the minimum word duration was 8 frames (0.12 sec on a 67 Hz display). The minimum duration for slower presentations had the same proportional relation to the base reading as the 300 wpm condition.

RESULTS: In the blocks of trials with variable word duration and a minimum there was no difference in reading rate for readers with normal vision across the four timing conditions (Wilcoxon rank sums p = 0.28) but there was a decrement in reading rate without the minimum (Wilcoxon rank sums p < 0.0001). Readers with macular degeneration did not benefit from the addition of the word duration minimum (Wilcoxon p = 0.26). They read more rapidly in the NO minimum condition when formula exponent was set at 0.5 (Wilcoxon p = 0.01.

CONCLUSIONS: A variable duration word exposure for RSVP based on word length does not improve reading rates in normal vision but adding a minimum word duration eliminated the decrement in reading rate that was previously reported. Including a minimum word duration reduced the reading rate advantage for low vision patients with AMD.
Affiliation of Co-Authors State University of New York, College of Optometry, Boston University, School of Medicine, State University of New York, College of Optometry
Outline