Abnormal pitch mismatch negativity in individuals with schizotypal personality disorder

Abstract

Background The goal of the study was to examine mismatch negativity (MMN) in schizotypal personality disorder (SPD) individuals. Abnormal MMN has been a consistent finding in chronic schizophrenia and there are also have been reports of reduced duration MMN in first episode schizophrenia patients (Umbricht & Krljes, 2005), with some studies finding no pitch MMN amplitude differences (Salisbury et al., 2002) while others reporting a modest reduction (Umbricht et al., 2006) in recent onset schizophrenia patients. To our knowledge no reports exist of MMN in SPD individuals. Methods Twenty six normal (14 females) control and 23 SPD (12 females) individuals were tested using the pitch MMN paradigm. Normal control (NC) and SPD individuals were recruited from the general population and assessed using DSM-IV. SPD individuals were included if they met 5 or more criteria for SPD disorder. The subjects listened to 2000 frequent 1 kHz pure tones and 100 rare 1.2 kHz pure tones while reading a magazine article. MMN was measured from a difference waveform within the latency window of 175–276 msec. Results Reduced MMN amplitude was found in SPD relative to NC subjects (p< 0.045). Conclusions These results point to potential differences between SPD and schizophrenia, where no reduction in MMN was found in most studies of first episode patients.

Mismatch negativity and low frequency oscillations in schizophrenia families

“…Our study that included a much larger group of family members revealed essentially the same pattern. One study in SSP subjects also showed reduced MMN (Niznikiewicz et al 2009), which was also replicated by the current sample. Therefore, our study provided simultaneous replication of several key features of MMN previously found in schizophrenia patients, their family members, and in individuals with SSP traits.…”

Mismatch Negativity in First-Episode Schizophrenia

“…34 Of the remaining 20 articles, one measured MMN in prodromal patients, 36 another in individuals who were ultra-high-risk of developing schizophrenia, 36 and another was on schizotypal personality disorders. 37 One article did contain first-episode patients, but combined MMN responses with those from individuals with chronic schizophrenia. 38 Sixteen studies remained that were further assessed.…”

Auditory steady state response in the schizophrenia, first-degree relatives, and schizotypal personality disorder

“…Brenner et al (2003) reported that ASSR power to amplitude modulated tones was unaffected across a wide range of stimulus frequencies in a small sample of persons with SPD ( n =11). However, abnormalities in auditory EEG and event-related potential (ERP) response (Niznikiewicz et al, 2009; Shin et al, 2010) and reduced volume of the superior temporal gyrus (Dickey et al, 2002; Goldstein et al, 2009; Takahashi et al, 2010) in SPD suggest potential impairment in the auditory pathways. First-degree relatives of schizophrenia patients share genetic and environmental risk factors with SZ patients in the absence of psychosis and are not typically prescribed antipsychotic medications.…”