Abstract
This review explores multi-tasking human in today’s technological advanced world where people are bombarded with information from multiple sources. Humans have to multi-task either out of choice or due to the nature of their work. As per research, humans are not designed for multi-tasking and can only do one thing at a time. We are trying to do things simultaneously but research indicates that we can only switch our attention from one task to another quickly and this has resulted in unsafe conditions in our personal and professional environments. There has been limited research on how human behaves, interacts and deal with the information overload but the topic has started to pick up steam as our world is infiltrated with smart technology.

The rise of technology – computers, internet, smartphones, tablets and social networking have wrought changes in human psychology that alter how we process information, make decisions and perform our daily tasks. Imagine a middle-aged commercial pilot waking up, getting ready to go to work, checking his work schedules, email, social networking status and talking on phone. Doing all this and more while rushing to get to the airport. Once at the airport, he has to pre-brief, plan and get ready for the flight ahead amidst all these distractions. This daily routine is not just common for our flyers. We can see similar rise of technology in all work fields – military, law enforcement, medical, engineering, maintenance, drivers and others.

The rise of technology has led to fast-paced lifestyles and a complex world. In this complex world, our brain is bombarded with information and multiple things are in a constant battle for our attention at any given moment in time. This overloading of information causes time constraints and can lead to frequent interruptions creating problems for our limited brains (Taslitz, 2012). On top of this, humans are goal oriented and are not always content with one thing at a time. Frequently, we will multi-task to attain multiple goals simultaneously (Sanbonmatsu et al., 2013). This may enable people to do more and achieve their goals, however, multitasking is cognitively and physically taxing and leads to diminished performance, inattention, and errors, reduced vigilance, reduced productivity and diminished judgment. Research on decision- making (Ajzen, I., Fishbein, M., 1980) indicates that willingness to multi task should be contingent, in part, on the expected outcomes or consequences. In other words, people expecting higher rewards at lower costs tend to prefer multi-tasking.

So, what is multi-tasking? The word ‘multi-tasking’ implies performing two or more pieces of work simultaneously (Anderson et al., 2005). For example: Driving and talking on the phone (even hands free) simultaneously. Considering the infiltration of cell phones in our lives, it is safe to assume that we multi-task at all times whether driving our cars, or performing our official duties. It also seems obvious that multi-tasking is not a matter of choice; it may be imposed upon us due to the nature of our work (pilots, police officers, military, medics). This is especially true for the drivers. This increase in spatial flexibility for communication leads to many drivers now engaging in multi-tasking behaviors (Strayer, D., 2003). In order for us to understand multi-tasking and its effects, we have to delve deeper into the topic of “Attention”.

Attention can be defined as the conscious or non-conscious engagement in perceptual cognitive, and/or motor activities before, during and after performing skill (Magill, 2001). There are two categories of attention theories. First, theory suggests that a single central resource or pool of attention is available to the individual (Kahneman, 1973). According to this theory, multi-tasking performance is possible as long as the total resource required for all tasks does not exceed available capacity (Kahneman, 1973). Second, theory suggests a multiple resource model (Wickens, 1992). This theory proposes that attention is distributed among various resource pools with their own unique capacity and resource-performance relationship (Wickens, 1992). As per this model, ability of an individual to multi-task depends on the demands placed on attention and which pool the demands originate from. If the demand came from the same pool, the tasks will be performed less well, and if the demand comes from a different pool of resources, task performance is unaffected (Wickens, 1992). Driving and texting is a perfect example to summarize the second theory. We may think that dialing the phone or texting while driving will lead to more accidents rather than talking on phone. However, it was found that risk of being involved in a motor vehicle accident while on a cell phone was four times higher than when not using the phone (Redelmeier, Tibshirani, 1997). Therefore, performance decrements result from multi-tasking behavior. These decrements appear to occur due to limitations in information processing capabilities, not as a result of motor output interference (Anderson et al., 2005).

It is also suggested that multi-tasking success is determined by various factors such as age, arousal levels, experience, stages of learning, and situation. A pilot for example would have to multi-task frequently during the course of the flight and all above mentioned factors would affect his/her ability to multi-task successfully. We are also aware of restricted nature of attention (Abernethy, 2001) or a limited availability of resources creating a bottleneck in information processing (Logan & Gordon, 2001). So, while multi-tasking, allocation of resources that include input/output (auditory/visual, manual/vocal), processing codes (spatial/verbal), and information processing stage (encoding/processing/responding) to each system would depend on the required task (Abernethy, 2001; Magill, 2001).

Age is the second factor that has been researched to show an affect on performance in multi-task environment (Branscome et al., 2007). Research indicates that older adults (60 years and older) perform poorly in multiple task environments than do younger adults (20 to 39 years of age), but there are several explanations for this decline (McDowd, 1986; Sit & Fisk, 1999). Age related performance deficit could be attributed to the task complexity and division of attention in older adults. Salthouse (1990) found that as more demands were placed on available processing resources, older adults showed greater impairment of performance than younger adults. However, Sit & Fisk (1999) found that age-related gap in performance decreased with practice. The third factor that may have an effect on our multi-tasking ability is personality. A study conducted by the Defense Women’s Health Research Program indicated significant differences in cognitive performance for individuals scoring high on the Impulsive-Sensation Seeking subscale (Mullins & Fatkin, 1999). Another study showed that high sensation seekers performed better in the primary task with no trade-off between their stronger attention to the primary task and their performance of the peripheral task (Ball & Zuckerman, 1992). However, it is not clear whether performance would diminish if sustained attention were required. Individual differences in temperament, such as risk-taking components, have been predictive of workload perception and preferences but more research is required to ascertain the role of personality (Driskell & Salas, 1996).

Based on these factors, multi-tasking can have serious effects on an individual’s task performance, analytical abilities and problem solving skills. Again, the research community is divided on these effects. Some believe that multi-tasking has no effect on individual performance and their analytical or problem solving skills whereas other’s believe that multi-tasking is not possible and individuals are merely jumping from one task to another back and forth which results in low quality/standards of work and increased stress. If we take an example of a student, research suggests that current students have a different attention span focus than those in the past because they are spending more and more time using multiple forms of electronic media while studying. These various stimuli let’s students interact with knowledge and/or entertainment simultaneously (Foehr, 2006) and has caused deterioration in student performance on individual tasks (Ophir, et al., 2009). Research also suggests that amount of total brain activity decreases when several media devices are used simultaneously (Just, Carpenter, Keller, Emery, Zajac, & Thulborn, 2001).

Finally, we may think that we are being productive, when we are trying to tackle multiple tasks simultaneously. This happens because it lets us believe that we are spending less time on each task. Another negative effect of multi-tasking is that we are more easily distracted which can result in errors and stress. Apart from errors and a false perception of efficiency, multi-tasking can also temporarily changes the way our brain works (Allen, 2013). While the right and left sides of the prefrontal cortex work together when focused on a single task, the sides will switch to independent functioning when we attempt multiple tasks simultaneously (Allen, 2013).

In conclusion, technology has definitely revolutionized our lives whether we are working in aviation industry, medical field, Law-enforcement on armed forces. Multi-tasking seems to be a necessary skill but recent and limited research indicates, humans are not ready to process a lot of information simultaneously. The negative effects of performance, analytical skills and decision-making are well established. These negative effects can somewhat be reduced with new training designs, however, human attention span is limited and unless we evolve to have more than two frontal lobes in our brain, multi-tasking should be considered with caution!

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