Rulers And Reaction Times Essays - Cognition, Mental Chronometry

Rulers And Reaction Times Rulers and Reaction Times Abstract The reaction time of ten subjects was measured. The subjects were asked to catch a ruler ten times under five different conditions. The first condition measured the subject's simple reaction time. Each further condition added an additional stimulus and the reaction times were measured. There was a clear increase in reaction time with the addition of further stimulus, however the expected result of a steady increase in response time with the addition of each condition did not occur. The third condition displayed the highest response time where as the final condition displayed the second lowest (after condition 1). Assuming that no design problems in the experiment affected the results, it cannot be concluded that cognitive processes occur in separate order and do not overlap. Given the average reaction time of condition five was lower than condition three, some cognitive adaption may have occurred to lower the response time of the subjects or another reason may exist. One aspect not c overed by the experiment, but important to the results was the error factor. Pre-guessing the experimenter caused a high rate of error, however it lowered the overall results. Why measure response times? As the world moves forward with technology, increasing pressure is placed upon humans to be quicker, be smarter and to operate more efficiently. As the population increases systems are being put in place to reduce incidences and accidents occurring. An example of this is a study conducted by Cameron, 1995 examining the influence of specific light colors, motor vehicle braking and the reaction time of the drivers to these specific clouds and conditions to avoid rear end collisions. Donders subtractive method holds that reaction times can be obtained by subtracting the simple reaction time; or subtracting type A from type B etc. (Cameron, 1995). Given this, it stands that the more stimulus provided (or thought processes required), the longer the response time of the subjects. This theory is tested in the measurement of ten responses to five test conditions. The trial provides preliminary information to participants and it is expected that reaction times will be shorter than if no infor mation was supplied. (Rosenbaum, 1980.) Method Participants Ten participants were selected, four female and six male. Ages ranged from twenty-two to fifty three. All were fully able bodied and from English speaking backgrounds. Materials A plastic yard rule was used. The yard rule was six centimeters in width. Procedure Condition One The experimenter sat one subject on a chair and instructed them to place their arm out in front of them at a comfortable height. The yard rule was then placed between the subject's fingers at a height of 10 centimeters. The subject was then told the condition 1 (Appendix A) and given three trials. The subject then completed the ten tries at the condition and the results were recorded. All ten subjects were tested in the same manner. No abnormal results were obtained. Condition Two The experimenter sat one subject on a chair and instructed them to place their arm out in front of them at a comfortable height. The yard rule was then placed between the subject's fingers at a height of 10 centimeters. The subject was then told the condition 2 (Appendix A) and given three trials. The subject then completed the ten tries at the condition and the results were recorded. All ten subjects were tested in the same manner. An error rate and abnormal results occurred. Condition Three The experimenter sat one subject on a chair and instructed them to place their arm out in front of them at a comfortable height. The yard rule was then placed between the subject's fingers at a height of 10 centimeters. The subject was then told the condition 2 (Appendix A) and given three trials. The subject then completed the ten tries at the condition and the results were recorded. All ten subjects were tested in the same manner. An error rate and abnormal results occurred. Condition Four The experimenter sat one subject on a chair and instructed them to place both their arms out in front of them at a comfortable height. The yard rule was then placed between the subject's hands at a height of 10 centimeters. The subject was then told the condition 4 (Appendix