I found this paper interesting. The paper is annoying trapped inside a Word document, which is about as bad as the standard PDF situation but bad in different ways, so I've included here the abstract, the conclusion, and a choice quote from the middle of the paper that captures the author's thesis.
I'm not very convinced that the author is right because his thesis is somewhat vague and depends on a vague definition of "cognitive control" (explained in more detail in the paper, quick Googling didn't turn up a straightforward summary of the concept, though the author claims it is a common term within neuroscience even if different authors mean slightly different things by it), but this is a more detailed account of mind wandering than I've seen before, and it gets points in my book for offering testable predictions that may confirm or deny the theory.
I seek an explanation for the etiology and the function of mind wandering episodes. My proposal – which I call the cognitive control proposal – is that mind wandering is a form of non-conscious guidance due to cognitive control. When the agent’s current goal is deemed insufficiently rewarding, the cognitive control system initiates a search for a new, more rewarding goal. This search is the process of unintentional mind wandering. After developing the proposal, and relating it to literature on mind wandering and on cognitive control, I discuss explanations the proposal affords, testable predictions the proposal makes, and philosophical implications the proposal has.
The possibility is this. Depending on the cognitive control system’s model of the value of various control signals, in cases containing relatively little expected value the system may select a package of control signals leading to exploration. These would be cases in which the goal is to find a new and better goal. And the method, which remains here unclear – although one could imagine it involving shifts of attention, construction of task sets involving imagination, inhibition of current goals, etc. – might be generally described as disengagement from the present task in order to set out upon a search for a more valuable task.
The cognitive control proposal, then, is this. Mind wandering is caused by the cognitive control system precisely when, and because, the expected value of whatever the agent is doing – usually, exercising control towards achievement of some occurrent goal – is deemed too low, and this ‘too low’ judgment generates a search for a better goal, or task. Perhaps, for example, the estimation of expected value dips below a value threshold attached to the package of control signals that generate exploration for another goal, or task. Or perhaps the value is always computed in comparison with available options, such that mind wandering is sometimes initiated even in the face of a rewarding current task.
This is a straightforwardly empirical proposal, and should be assessed in terms of the explanations it affords, and by whether the predictions it makes are confirmed or disconfirmed.
In this paper I have asked why the mind wanders. I focused on a sub-type of mind wandering – mind wandering that occurs independently of any reportable intention. I proposed that unintentional mind wandering is sometimes initiated and sustained by aspects of cognitive control. Unintentional mind wandering is caused by the cognitive control system precisely when, and because, the expected value of whatever the agent is doing – usually, exercising control towards achievement of some occurrent goal – is deemed too low, and this ‘too low’ judgment generates a search for a better goal, or task.
This proposal generates testable predictions, and suggests open possibilities regarding the kinds of computations that may underlie unintentional mind wandering. My hope is that by connecting research on mind wandering with research on cognitive control resource allocation, fruitful strategies for modelling these computations may be taken from cognitive control research and deployed to help explain the initiation and dynamics of mind wandering episodes.
The cognitive control proposal also points us towards a fuller picture of human agency. On this picture, action control and intelligent thought are stitched together by conscious and non-conscious processes operating in concert. Future empirical work is critical to confirmation of this picture, and to filling in the many unspecified details. This is so not least because, if the proposal I offer is on track, agents are not introspectively aware of the (good) rationale behind many mind wandering episodes.