Deictic and propositional meaning – new perspectives on language in schizophrenia.
While schizophrenia is generally considered a thought disorder, its symptoms are to a large degree observable through language. We learn via language about a person's thought disorder and delusions, and most hallucinations in schizophrenia concern hearing voices. Negative symptoms (for example lethargy, aphathy) as well go with changes in communication.
One question that may turn out to be important for understanding schizophrenia, and possibly clinical practice, is whether people with schizophrenia only differ in what they say (for example, if they claim that the Queen is their aunt), but whether they also differ in how they say it. Does schizophrenic language have specific lexical or grammatic features? According to the research so far, yes, it is. There can be deviations in lexical selection, clauses are less connected to each other, and there can be an overall decrease in grammatical complexity.
In this article, an output from the "Language and Mental Health" project of which I was a member, we look at major symptoms in schizophrenia, in particular thought disorder and delusions, and frame them within a linguistic context. Language output in people with schizophrenia can be very confusing for the listener. Important information may be missing, contradicting or simply implausible. We try to capture this behaviour using two concepts: deictic reference (To which entity or entities is the person referring to?) and propositional meaning (What is the person stating about these entities?). As we lay out in the paper, both are not simply mental phenomena, but lie at the core of language function and can be mapped to particular lexical and structural properties. Thinking about some schizophrenic symptoms as disruptions of deictic reference and propositional meaning cen help identify language properties which may turn out to be important for identifying people at risk, diagnosis and treatment.
When I linked to the article on Facebook, three of my colleagues said that they are currently giving lectures in this topic. It seems that language researchers have become more aware of schizophrenia, about which, when I did my Masters in the first half of the noughties, I heard nothing.
This is a short, open access article written with non-linguists in mind, so instead of elaborate here, I will simply ask you to have a look at it even if you are not a language researcher. I do however want to reflect a little on writing a "perspective article", working on it with psychiatrists and a philosopher/linguist, and publishing it in a Frontiers journal.
There is something powerful about a project that brings together philosophers, psychiatrists, linguists and cognitive scientists. This is an ambitious, multisite endeavour. On the other hand, it is easy to underestimate how barriers between the fields could impact on every step of the research. Not only did we differ in our knowledge base and teminology, motivations between "camps" differed vastly. Some want to focus on behavioural cognitive therapy, others want to make a point about the nature of language and thought. Others are interested in neurological processing. It's not that no one cares about the others' goals, or that these differences make collaboration impossible - it's just that they require a lot more time and organization than I thought, and frankly more than we could muster. In a way, the order of contributors in this paper is evidence for these difficulties. I admit that of all authors I am the least qualified to write about schizophrenia with much confidence. While I certainly contributed substantial ideas, I became first author mostly because I am the person who was able to translate thoughts into a language that was clear to everyone, and with which everyone agreed. It was a difficult situation for me, and while I learned a lot and am happy with the result, I am not sure if I want to be in such a place again.
This is my first article which does not contain an empirical report, and as such I was a bit naive about publishing it. Most journals favour empirical reports of systematic reviews. If you write a piece like ours, you should really make sure that a journal has invited you. As an uninvited piece, many editors will hardly look at it. So when it came to submission, there were not many options. In the end we went with Frontiers in Psychiatry despite, and in a way because, its slightly predatory nature. Having co-edited a special issue for Frontiers in Psychology I knew how hard it is to get rejected by a Frontiers journal, and I saw little chance to have this article published in any other journal with a notable impact factor. I am not criticizing the content of articles in Frontiers. In all cases in which I have been involved, authors, reviewers and editors took much care. But readers should be aware that Frontiers is a pay-to-publish journal working with a system that is biased towards accepting papers.