Performance load is the “degree of mental and physical activity” (Lidwell, Holden, & Butler, 2010) necessary for the completion of a task to achieve a result. A high performance load means that the probability for a person to make mistakes is higher and the chances of proper completion of the task decrease. There are two types of performance load: a. Kinematic Load This indicates the amount of physical exertion required to complete a task. For instance, a telegraph machine was purposefully built in a way that reduced kinematic load. This was done by making the most commonly used letters require less “taps” than their counterparts. This made the overall physical energy required to send a message much lower. b. Cognitive load. On the other hand, cognitive load has to do with the mental exertion required for a goal to be accomplished. As an example, () mentions the use of the graphical user interface in modern computers. As opposed to newer computers which did not require a typed set of very specific text to get any work done, older computers had a much higher cognitive load. Good design involves using methods to reduce cognitive and kinematic loads. This can be achieved by methods such as chunking and automation to reduce the monotony of repetitive actions.
Lidwell, W., Holden, K., & Butler, J. (2010). Universal principles of design Retrieved from Ebook Library http://public.eblib.com/choice/publicfullrecord.aspx?p=3399678