Data Collection and Processing
In this experiment, the reaction time of visual and tactile response has been investigated by measuring how both hands reacted when eyes were open and then when eyes were closed. For a better comparison of the two, the averages have been compared as well. The ruler’s centimetres have been turned into time counted in seconds using the formula;
- The tactile responses where faster to visual stimuli presented
- As time passed, the reflexes where becoming reasonably ‘slower’, however, at some point, it was easy to expect when the other student would let go of the ruler due to the many trials.
Using the measurements obtained from the above tables, graphs have been organised so as to better comprehend the outcomes of this experiment.
- In general, the right hand seems to have a faster response to tactile stimulation than visual one.
- Some values seem to not comply with the rest of them, probably due to the existence of other factors affecting the outcome of the experiment.
- In general, the left hand seems to have a faster response to visual stimulation than tactile one.
- Some values seem to not comply again with the rest of them, probably due to the existence of other factors affecting the outcome of the experiment.
- Overall, the tactile responses seem to be faster than the visual ones, dependent nevertheless from factors such as left-handedness and/or right-handedness.
- The left hand had a faster response to the visual stimuli compared to the right hand
- The right hand had a faster response to tactile stimuli than the left hand. Bearing the previous observations into consideration, a relation could be made between different parts of processing the stimuli (spinal cord and brain) and the reactions of each of the hands and hence the brain’s functioning.
From the graphs, it becomes evident that tactile responses are faster than the visual ones. Furthermore, from the averages, we can conclude that the two hands much varied in their performance of the visual and tactile responses. It has also been observed that some of the values do not comply with the general tendency of the other results, thus indicating the existence of other, uncontrolled, factors affecting the results.
Conclusion and Evaluation
As our literary sources command, the main function of our nervous system is the coordination of rapid responses to stimuli, including reflexes. A stimulus is a change in the environment which is detected by receptors. Once perceived by the organism, a certain response is elicited and a change in the organism occurs. In this experiment, we investigated the speed of a human’s response to tactile and visual stimuli.
The findings of this experiment agree to the fact that our tactile responses (performed with closed eyes) are considerably faster from our visual responses (performed with the eyes open). This happens because the signal transmitted from the sensory neurons of our eyes is directly processed by our brain, whereas the signal received from our skin, as the feeling of touch, is processed at the spinal cord and are involved with the local segmental reflexes. As the results of this experiment agree to the general knowledge given from various other literary sources, it can be characterized as reliable.
Despite the many efforts to control for the confounding variables which might affect the very outcome of the experiment, some values have been observed to not comply with the general rule, generated by the rest of them. A number of factors could be responsible for this.
- In order to make the measurements of height, a ruler has been used, causing the possibility of error to rise. The possible error that might have been involved is that of a 0.05cm
- At times, the ruler was not caught at all by the participant and the trial was repeated until a positive number was achieved. It could be argued though that these times are important as well since the inability to react fast could be thought of as a visual or tactile response.
- External factors might have affected the results of this experiment. Even though it was conducted in a laboratory, noise or distraction could have occurred due to the other classmates.
Ways to improve the methodology of the experiment
- A control of the external confounding variables, such as noise, could help the experiment acquire more focused results.
- A more precise ruler could have been used
- A second verification of the data would be beneficial to the better support of the results found. It would also be good if more participants were used as well.
- The participants to this study should not be aware of the theoretical points in biology, which would affect their performance due to biases.
Suggested future work, related to this study and its theoretical points, could involve the study of how fast a message is transported through the nervous system or how can this speed be affected by variables such as attention and stress or other neurological conditions. Moreover, individuals could be assessed with visual and tactile stimuli so as to test the different responses between the reaction time of their left and right hands, correlating the results to whether they are left-handed, ambidextrous or right-handed.