Saturday, November 03, 2018

Closure of the secondary task


Closure of the secondary task

This is a short note on the closure of the secondary task when attention is divided between a primary and secondary task.

"Ergonomically speaking, when one has a multi-task assignment, the primary task is the one that takes priority. That is, it is the task that should receive the largest amount of allocated mental and physical resource. All other tasks in the assignment are dealt with in later order.[1]"

"Ergonomically, any job which is subordinate or incidental to the primary job where multiple tasks are required for completion.[2]"

From the point of divided attention the secondary task does not have to be related to the aim or context of the primary task.  Listening to music while driving a car for example.

The attention necessary for the primary task may be reduced in some cases.  Predictability, repetitiveness, processing speed of events that have to be perceived are some of these.

The reduction of attention resources for the primary task increases the resources of the secondary task.

Also the increase of need for attention resources for the primary task reduces the resources for the secondary task.

While driving and listening to radio at the same time, in the case of a difficult situation, the driver does not hear the radio anymore (-till the emergency is solved).

In the case of emergency, the second task closes temporarily without conscious decision. 

This automatic closure of the secondary may become a deadly danger when primary and secondary tasks are mixed unintentionaly.

Talking while driving may cause a similar risk if the talk becomes serious and elaborated.  The secondary task, namely 'talking' gets hot and the driver does not become aware that his primary task, 'driving' has become 'secondary'. 

The worst of it happens when the 'talk' becomes the primary task and causes the second task, 'driving's closure automatically.  The driver does not notice that he is not in control of the vehicle.

Technically speaking, the man machine embodiment has been destroyed and situation awareness is lost.

This is one of the reasons we sometimes suddenly wake up to a risk on the road and try to correct it.


[1,2] Nugent, Pam M.S., PsychologyDictionary.org, April 28, 2013