To the Editor.—
Shenton et al1 recently reported that the relatives of psychotic patients exhibited more thought disorder than normal control subjects. They also found that probands with higher thought disorder scores tended to have first-degree relatives with higher thought disorder scores. This was a well-conducted study, and the results are important for anyone who wishes to understand the phenomenology and etiology of schizophrenia.My colleagues and I2 have previously reported that we did not find evidence of genetic influence on formal thought disorder in speech samples taken from the Gottesman-Shields twin sample. In addition, with the exception of verbosity, we did not find evidence of nongenetic familial influence. Thus, there appears to be a discrepancy between the two studies. Shenton et al found evidence of familial resemblance; with the exception of verbosity, we did not. Shenton et al proposed that the reason for the discrepancy is that
Berenbaum H. Distinguishing Between Content and Form of Speech. Arch Gen Psychiatry. 1991;48(3):280. doi:10.1001/archpsyc.1991.01810270092017
Customize your JAMA Network experience by selecting one or more topics from the list below.