"The man thinks that it is cold outside."
As part of the AHRC-funded "Language and Mental Health" project we tested comprehension of factive, non-factive and counterfactive constructions in people with aphasia and schizophrenia. We are publishing the testing materials on this website.
These sentence types are an important aspect of child development research, as they relate to questions about word and grammar acquisition as well as the emergence of other capacities such as Theory of Mind. It seems that with regards to aphasia and schizophrenia, we were the first to explore processing of these sentences. Let me quickly introduce them.
In factive sentences, such as "Peter knows that there is juice in the fridge", the proposition in the embedded clause ("there is juice in the fridge") is presupposed to be true.
In non-factive sentences, such as "Peter thinks that there is juice in the fridge", there is no such presupposition. There may be juice in the fridge, there may be none. Further, the person uttering this sentence may know or not know about the contents of the fridge.
In counterfactive sentences, such as "It only seems to Peter that there is juice in the fridge", the embedded clause is presupposed to be false.
Tests of comprehension of these constructions have involved a variety of methods. We decided to design a sentence-picture matching task for our study, considering that it is the standard paradigm in clinical language testing (e.g., CAT, TROG). This makes it easier to integrate our results within the field.
The test presents factive sentences in factive contexts (matching picture shows embedded clause to be true), and non-factive and counterfactive constructions in counterfactive contexts (matching picture shows embedded clause to be false).
The test takes about 10 minutes. The download contains a .pdf with instructions, test sheet and pictures, as well as a .xlsx file for automatic scoring.
There are some limitations, and we make suggestions for improvements. Please read the manuscript linked below for more information and our results from aphasia (schizophrenia results will be published as a separate paper).
Please refer to:
Zimmerer, V.C., Varley, R.A., Deamer, F., Hinzen, W. (under review). Factive and counterfactive interpretations of embedded clauses in aphasia and their relationship with lexical, syntactic and general cognitive capacities.