Well, I hope that you, readers, were able to picture for yourselves how a preliminary, or pilot experiment regarding observations on the state of a patients’ brain, and the occurrence of certain specific compulsive behaviours might be conducted. If the outcome of such a little project is promising, larger studies can be designed, preferably involving many more test persons, and more precisely defined parameters that are important (e.g. a broader scale of dilutions of substance X).
But, the thing is… are we able at all to ‘go into’ human brains with such-and-such substances, as I described? The initial answer is a flat ‘no’.
Humans are fragile beings, and bodily manipulations for scientific purposes are a sensitive, often controversial thing at any rate. This is much, much more the case when it comes to our brain. We cannot just go in there and change conditions to our hearts’ content, to see what these changes bring about. Not for nothing is it that in relation to the brain, the adjective ‘invasive’ occurs so often. That means: intruding, entering.
The chance that in manipulating the brain, some irreversible effect (e.g. in the form of damage) is caused, that chance is always there and must be taken into account. An illustration of this fact is that in grave psychiatic and/or neurological conditions, ‘drilling the skull’ and going into the brain mass is always the last option under consideration.
There are people with forms of OCD that are highly treatment-refractory. This term means that they don’t respond well, or not at all, to the most efficacious treatment options we know: pharmacotherapy, cognitive-behavioural therapy, and /or psychotherapy in the broader sense. And even in case of a very moderate response, it is still possible that severe relapses into illness happen. For these people, clinicians may eventually consider neurosurgery. In practice this can constitute diligently severing a few nerve tracts, e.g. in overactive circuits, or causing another form of very mild lesion, in an attempt to decrease symptoms. Yet another option is inserting a pacemaker-like module into the brain, which produces series of electrical impulses; this method is called deep-brain stimulation (DBS).
The interventions described above are invasive: surgeons have to open the skull, and very carefully do work in finely circumscribed areas of the brain, that are involved in the pathology of OCD. Often you see the word ‘stereotactic’ in this context: this means that work is being done using a super-precise threedimensional mapping of the brain. To do that, delicate contraptions are available, to keep a person’s (or an animal’s) skull in exactly the same spot over an extended period of time.
Oh, and: we will go deeper into the notions hinted at in the above, including the types of neurosurgery available today.
The upshot: in theory the manipulation of internal conditions in a person’s brain, on behalf of scientific research, is all fine and dandy – but for ethical reasons, and because there’s always a risk for unwanted side effects such as unintentional lesions, the practical possibilities in this field are limited, and oftentimes researchers resort to animal models of OCD. These will then constitute a topic in the future for us.