Is workaholism similar to any addiction or are there other neurological mechanisms at play? Some people are seemingly 'addicted' to their work and by doing work itself, almost to the point of precluding all other activities and interactions (usually social).  By this question, I mean when people go beyond a 'passion' for the work, into an almost obsessive approach.  (I have met a few people like this).

Is this addiction to work similar to other addictions?  or is there something else triggering this almost obsessive work-ethic to the preclusion of almost all other activities?

I am after peer-refereed articles about any studies that have been performed on this.
This is a great question - one that resonates with me especially when reflecting on my own professional life.

My answer to your question would be both speculative and (hopefully) empirical. From personal experience, I have met people in my professional life that may exhibit 'workaholic' behaviours but it is unclear whether it is driven by fear and anxiety or behaviours aligned to values to achieve almost perfect work performance.

I would start with defining precisely what workaholism is. Spence and Robbins (1992) defines a workaholic exhibiting three specific properties:


  
  Highly work involved
  Compelled or driven to work because of inner pressures
  Low in enjoyment of work
  


If we compare those properties against an addictive disorder such as Bulimia Nervosa, some surprising similarities arise. Compensatory self-vomitting behaviours tend to be a product of overevaluation of body weight and shape (Lamparda et al., 2011). Let's assume that "inner pressures" represent an individual's need to achieve their body weight and shape. Analogously, "inner pressures" such as perfectionism and responses to fear can cause this seemingly addictive workholic behaviour. I would dare say that the cognitive processes involved between these two cases would be quite similar.

Examining workaholism from a neurological perspective, in my opinion, would mimic neurological studies on addictive disorders. However, I couldn't find much. Randles et al. (2010) make reference to neurological mechanisms in describing how perfectionism and rumination can contribute to goal-oriented behaviours. 

The drive to work harder and harder is likely to be influenced by the level of perfectionism and anxiety experienced by an individual (Shafran &amp; Mansell, 2001). Catastrophising and ruminating about work performance can theoretically compel an individual to work harder to the point of psychopathology (of course, we lack the criteria). On another note, personality traits such as narcissism would probably play a role in triggering workaholic behaviours.

References


Spence, J.T. &amp; Robbins, A.S. (1992). Workaholism: definition, measurement, and preliminary results. Journal of Personality Assessment, 58(1), 160-178
Lamparda, A.M., Byrnea, S.M., McLeana, N. &amp; Furslandb, A. (2011). An evaluation of the enhanced cognitive-behavioural model of bulimia nervosa. Behaviour Research and Therapy, 49, 529-535
Randles, D., Flett, G.L., Nasha, K.A., McGreggor, I.D. &amp; Hewitt, P.L. (2010). Dimensions of perfectionism, behavioral inhibition, and rumination. Personality and Individual Differences, 49, 83-87
Shafran, R. &amp; Mansell, W. (2001). Perfectionism and psychopathology: A review of research and treatment. Clinical Psychology Review, 21(6), 879-906.