UvA researcher Denny Borsboom continues to work towards a network model for explaining mental disorders. Through such a model, he also hopes to contribute significantly to shaping new theory in his field. He received an NWO Vici grant for his work.
For most mental disorders, the exact underlying cause has never been determined. Still, in many cases, people continue to search for a so-called magic bullet – a single source or cause that could explain the disorder. With depression, for instance, researchers have long attempted to identify central causes in the brain, or in environmental or genetic factors.
‘It would, of course, be terrific if we could find a singular origin for a disorder like depression, because that could potentially make such a disorder much easier to treat. But unfortunately, we haven't,’ says Denny Borsboom, who works in the Psychology department at the University of Amsterdam.
Borsboom and his team have already given the theory surrounding disorders quite a shake-up with their earlier research and a model which demonstrated that it is actually an interplay of symptoms that offers a potential explanation for disorders such as depression. These findings neatly dispatch the idea of a single-cause explanation.
In their model, Borsboom and his team brought together symptoms that play a role in cases of psychopathology, uniting them in a network. Within that network, symptoms such as anxiety, alcohol abuse and lack of motivation display an interactive relationship in which they can reinforce one another. For instance: a person is sleeping poorly, they have to drag themselves to work in the morning and come home feeling apathetic, so they start to drink too much, and as a result they continue to sleep poorly. This creates a downward spiral of misery and can cause a person to end up in the stable state of symptom activation we refer to as depression.
‘The introduction of our network model and theory has had an enormous impact’
Borsboom explains: ‘In principle, the idea that symptoms interact with one another was already common knowledge. But with this model, it's now possible to construe the structure of those networks on the basis of data, and to truly extrapolate the development of disorders.’
With the research funding that Borsboom received from NWO Vici in March, he intends to further develop the network model with his research team.
‘How exactly do the components in our model, the various symptoms, relate to one another? What influence does the factor of time exert on the chain of symptoms? How do slow and quickly-advancing processes affect one another?’ Borsboom sets out the questions. ‘Right now, we don't yet know enough to answer them.’
So how do they intend to do this? By dividing the network into small modules, one for each symptom, which will serve to model the dynamics of that particular symptom. Next, those symptoms can be linked together to form a network. This will allow researchers to work together towards a larger theory – to which more and more knowledge will be added along the way – and which will ultimately be reassembled into a living, breathing whole.
They are inviting other scientists to add their own knowledge of a specific symptom to the corresponding module. Sleep researchers, for instance, could enrich the ‘sleep module’ with their expertise in the area of sleep and its effects. To make this a reality, Borsboom intends to reach out to as many disciplines as possible. He will also be studying inspiring models from other scientific fields, such as climate models, in order to learn how the makers of those models undertook and realised their creation.
‘In addition to a specific model, we also hoped this research would make a contribution to the field of psychology by showing how to establish a formal theory as the basis for extrapolation, and from which you can then derive verifiable implications. We can teach this methodology to students as well, so that they can experience first-hand how fun and creative the process of establishing formal theories can be,’ Borsboom explains.
Besides creating new theory for the field, the intended results also include a model that can be applied in practice and that can help us to better understand and combat disorders like depression that claim a heavy social toll.
The NWO (The Netherlands Organisation for Scientific Research) Vici grant is one of the largest individual scientific grants in the Netherlands and is aimed at supporting advanced researchers. A Vici grant of 1.5 million euros enables researchers to spend the next five years developing an innovative research line and establishing a research group of their own.