Auditory and Visual Reaction Time
S. LeaAnne Hart
September 10, 2018
Dr. Nicholas Murray
This lab discusses an experiment to show an onset of a stimulus to the initiation of a response. Reaction time is used in our everyday lives. There are many influences that affect the average human RT such as the number of response choices, anticipation, psychological refractory period, fore-period consistency, stimulus-response compatibility and the response time delays. Movement time and reaction time go hand in hand. MT is the initiation of movement to the completion of the movement. MT can be dependent or independent of the reaction time. Speed is a way to determine if the MT is one or the other. In this lab, I hypothesized that auditory reaction time is faster than visual reaction time and that movement time is dependent of reaction time.
For this lab, the class was split in half. One side of the room tested visual reaction time first and the other side tested auditory reaction time. We paired up in order to record each other’s data. The auditory RT clock allowed the students to test their movement and reaction time to the sound of a beep. After the beep, students had to stop the clock with their left hand as fast as possible. The test was done twice in order to get an average score of RT and MT. The first set of numbers were the RT and the second set were the MT. For the visual RT programmer, students also ran through this test twice in order to have an average of their scores. In this test, the clock was started by pressing a button on the keyboard to signal the clock to start. When the button on the monitor turned red, that was the signal for students to stop the clock.
The independent variable was the stimulus (external signal), whereas the dependent variable was the time it took to stop the clock. In the graph below, the mean for ART was 218.7778. When VRT was included, the mean was 300.3889. The mean difference between Visual RT and Auditory RT is 259.59. The Standard Deviations for the Auditory RT (stdev = 30.93) was fairly lower than the test for Visual RT (stdev = 44.07) and MT (stdev = 68.28). The fluctuation between all of the stdev shows that there is a low degree of association amongst the data.
The information that was gathered during this lab supported my hypothesis. The auditory cue produced a faster reaction time. The reaction time is significantly lower than that of the visual reaction time because of how the brain works. The hair cells are deep in the cochlea and the conductors for hearing are hair cells. When the soundwave gets to the hair cells, it is converted to an electrical impulse which goes down the auditory nerve to the temporal lobe. That is the brain structure that processes hearing. Another advantage of the auditory cue being faster is because everyone has two ears that can retain all noises around you and information distributes into your brain to process what is happening in your environment . Contrary to visual stimuli, the only information that is being captured is what is in front of you and your peripheral. Hearing cannot be turned off by closing your earlobes like you can close your eyes and turn off your visuals. Therefore, sound is always being processed and that is why the reaction time for auditory stimuli is faster than visual stimuli.
The correlation coefficient between the speed of reaction and the speed of movement suggests that the times are close together meaning they are dependent of each other. With a fast reaction time comes a fast movement time. The median score for VRT is 300, while following behind it is ART with is 216. Looking at MT, the numbers go back up to 280.5. The averages for these are fairly close to the median numbers. VRT totals to 300.39. ART’s average is 218.78 and lastly MT’s is 288.18. All of these numbers are closely related because they are dependent of each other. The standard deviation of movement time and reaction time shows that there is a low degree of association between the three. There were differences between the three because of the entire classes input. Everyone operates at different speeds and reacts either faster or slower. If everyone was the exact same there would be no difference in the reaction times or the movement times. This data can be applied to the real world because visual and auditory reaction time is used in everyday life. For example, avoiding a collision, catching an item that has fallen from the kitchen counter, or defending an opponent from driving or cutting to the hoop in basketball(Coker 31).
Coker, Cheryl A. Motor Learning and Control for Practitioners. Fourth ed., Routledge, 2018.