Performance Of The Two Tasks example essay topic
Inevitably at one stage in your life you will here the phrase "I can't do to things at once". Why is this the case, what reason does that person give. Possibly they are saying that it is hard to concentrate on both tasks at the same time. It's probable however that the person saying this has at one stage, performed two tasks at the same time before. Or have they?
Is the ability to drive a car and speak on a mobile phone the ability to perform two tasks at the same time, or if two tasks are being performed do we alternate our attention between the two task therefore only focusing on one at a time? A considerable amount of psychological investigation has looked at attention and how it plays a role in 'multitasking', (performing more than one task at the same time). Eysenck defines attention as being the 'taking possession of what seem several simultaneously possible objects or trains of thought. Focalisation, concentration of consciousness are of its essence'. Attention is often subdivided into two different categories, focused attention and divided attention.
Focused attention can be described as focusing on a specific stimulus input when numerous stimuli inputs are presented. e.g. focusing on exactly what the lecturer is saying and blocking out all those people who are talking around you. Colin Cherry was a British Scientist who worked in and electronics research laboratory. His main fascination was the 'cocktail party' problem. This describes how people are able to follow just one conversation when there many other conversations taking place around them. He also carried out auditory experiments by which participants were asked to shadow (repeat) auditory produced from one earphone whilst distracting auditory was produced from the other earphone. He found that little information was attained from the non-shadowed message so much so that participants would sometimes fail to notice when the non-shadowing message was in a different language.
This study therefore concludes that when focused attention is used we can accurately and successfully block out any unnecessary stimuli by channelling our focus towards the one stimulus that is important. This has implications on whether we are able to perform successfully two tasks at the same time as this study would assume that the two tasks would be to attend to auditory words coming from two different sources at the same time. This study would suggest that a person is unable to follow two conversations at the same time if attention is only focused on one of the people speaking, thus suggesting that focused attention is inadequate from performing two tasks successfully. Allport, Anton is and Reynolds (1972) also looked at focused attention but with a more specific aim then Cherry. They were concerned with what impact the degree of similarity between the two inputs had on memory for the non-shadowing message.
They found that with similar inputs e.g. audio and audio, memory for the words were very poor. However if the inputs were not similar e.g. visual and auditory representation of words, the memory for both inputs was far better. This shows inputs can be processed to a higher degree when they are different of a different source. So if the two tasks that are to be performed use different sensory inputs, the success of performing the task at the same time are likely to be far better than if the inputs use the same senses. e.g. If a student talks to a fellow student in class when the lecturer is also talking, they are less likely to learn what is being taught by the lecturer as the two inputs in this case are both auditory. Dived attention looks at the human ability to perform more than one task at once but Hampson (1989) suggested that focused and divided attention are more similar than what might have first been expected. Hampson discussed the idea that "anything which minimises interference between processes, or keeps them 'further apart' will allow them to be dealt with more readily either selectively or together".
So can we divide our attention equally between two tasks so that the performance of each task is successful? What could be better then being able to complete two essays at once simply by dividing your attention between two essay titles? Work loads would decrease as the time taken to complete both tasks would be minimised. So why is this not a universal method for completing work or performing tasks? A study by Wickets (1984) looked at the effects of task similarity. He concluded that the extent of which two task interfere strongly correlates to stimulus modality, (e.g. visual or auditory).
He went on further to say that within multitasking, the performance tasks, given the same stimulus modality, will interfere as they 'make use of the same stages of processing, (input, internal processing and output) '. So the implications of this in multitasking would suggest that if a given set of performance tasks use different stimuli modalities, divided attention and the ability to perform two or more tasks at the same time is superior to that when the tasks have similar stimulus modality. Central Capacity theories looks at the resources used to process set tasks. The 'central executive', often known as attention or effort can be compared to a computer storage chip.
The storage can hold only a certain amount of information if it is to stay functional. If we overload the chip, it is likely to have a detrimental effect on the processing performance. Relating this back to divided attention and multitasking, it implies that if the two tasks being performed do not exceed the resources of the 'central executive', the performance of the tasks will be successful. However if the tasks are complex and do exceed these resources, then output performance of the tasks is likely to be unsuccessful. So if our task is to walk and talk at the same time, our central capacity can cope with the tasks divided ly. If try to walk whilst balancing a spoon on our nose and also calculate Einstein's theory of relativity, the total input exceeds the resources available for processing and we may drop the spoon, fall over and miscalculate a vital equation!
Psychology researches have found that more often than not when we attempt to 'multitask' our time taken to perform the task increases and the accuracy in which the task is performed decreases. Most of the reasons for this have been covered above but another theory suggests that when two tasks are being performed simultaneously, we tend not to process the inputs at the same time but shift our attention from one task to the other. This therefore increases the time taking to perform the tasks as the time taken to switch from task to task increases. So this relates back to an earlier question; are we performing the tasks at the same time using divided attention or do we switch between tasks and use focused attention. This research would suggest that multitasking is not taking place; we are merely focusing our attention selectively on each individual task but not at the same time. Further arguments against multitasking come from Bottleneck Theories.
Wexford (1952) would argue that successful multitasking is almost impossible due the bottleneck within our processing system. This bottleneck would not allow for two decisions to be made in order to give an appropriate response to two stimuli simultaneously. The bottleneck when tested in dual tasking causes a delay in the second task being performed, suggesting that the first task has to be completed before the next is started. This waiting whilst the first task is completed is called the 'psychological refractory period'.
Practice makes perfect has become a well established notion for the idea that if you spend enough time performing the same task, that task will become easier over time. A first year student at university may go to their first lecture in biochemistry and come out of the lecture with only a couple of scribbles on their note pad. That student is unfamiliar with the techniques and lacks practice in the most efficient way for themselves to take notes. After the first semester the student will have attended many lectures and developed their own style of note taking.
Thus practice can be seen to improve performance. Psychology suggests that this improvement through practice is down to 'automatic processing'. Automatic process are said to be fast without the need of attention. They therefore do not reduce the capacity for performing other tasks. They are also unavoidable so when certain stimulus is presented, the appropriate response is given at an unconscious level, e.g. when drivers of motor vehicles come to a set of traffic lights that show green, they carry on driving. Relating this theory to the question of whether it is possible to multitask, it could be said that if one of the performed tasks uses automatic processing then the second task will almost only require focused attention as opposed to divided as no attention is being given the automatically processed task.
So if an experience driver of 30 years uses their mobile phone whilst driving, will the performance of each task be equal to the performance of the two tasks if they were done separately. Much research has gone into whether using a mobile a mobile phone whilst driving has a detrimental effect on the performance of driving. Due to these studies talking on a phone whilst driving has now become an illegal act as the studies have shown that the two tasks being performed at the same time leads to an unsuccessful performance in driving. This would then suggest that automatic processing does not aid multitasking.
Above we have looked at the contributing factors in whether it is possible to perform two tasks successfully at the same time. This however is slightly an ambiguous question as there is no true clear cut answer. Yes we can walk and talk at the same time without falling over due to the multitasking going on. However these tasks are simple and require little resources and processing. If on the other hand the tasks are more complex, we may be able to perform them but the outcome maybe an unsuccessful performance.
Bibliography
Eysenck, M.W., Keane, M.T. (2000) Cognitive Psychology, 4th edition, 5,119-150.
Rubinstein, J.S., Meyer, D.E., & Evans, J.E. (2001).
Executive Control of Cognitive Processes in Task Switching. Journal of Experimental Psychology: Human Perception and Performance, 27 (4), 763-797. Ko well, S. (2001) Executive Control of Cognitive Processes in Task Switching", published in the American Psychological Society's Journal of Experimental Psychology web web.