Thinking within the spectrum: schizophrenic thought disorder in six Danish pedigrees

Schizotypy and language: A review

“…In addition, Edell (1987) found that individuals with SPD had higher total TDI scores than control individuals matched on verbal IQ. In another study, schizophrenia patients' relatives with SPD scored higher than control individuals on a factor of TDI items that included autistic logic and absurd responses (Vaever et al, 2005). A limitation of the latter study was that it did not ascertain whether the groups differed on general intelligence, as such a difference could conceivably have contributed to the results.…”

Linkage and whole genome sequencing identify a locus on 6q25–26 for formal thought disorder and implicate MEF2A regulation

“…Evidence of specific neurobiological deficits characterizing FTD has come from imaging studies showing volume reductions in the left superior temporal cortex and structural brain abnormalities in language-related cortical regions (Sans-Sansa et al, 2013). In a previous study of the pedigrees which forms the basis of this study, Vaever et al, 2005 reported that patients with schizophrenia had higher global levels of FTD and exhibited more severe types of FTD than family members with other diagnosis or no mental illness. However, they did not find an apparent pattern of linear aggregation of FTD within the families.…”

“…Disordered thinking may refer to the content of thoughts or the mode of thinking; the latter reflecting semantic and/or syntactic failures in ordering the world and thus a fundamental ability of the brain of particular clinical relevance. Deficits in mode of thinking, generally termed formal thought disorder (FTD), are also present in milder but measurable forms in healthy relatives of patients with schizophrenia (Vaever et al, 2005). FTD has been reported to be highly heritable, and adoption and twin studies have documented the importance of genetic causality (Gambini et al, 1997;Kinney et al, 1997).…”

Formal Thought Disorder and language impairment in schizophrenia

“…FTD symptoms are not specific to schizophrenia patients, but rather are correlated to schizophrenia spectrum disorders 45,46 and to a family history of schizophrenia 47,48 . Wahlberg 49 found that adoptees of parents with schizophrenia showed more FTD symptoms than adoptees of normal controls.…”