The content of attenuated psychotic symptoms in those at clinical high risk for psychosis

Abstract

Recent research has started to focus on identifying individuals who are at clinical high risk of developing psychosis as a means to try and understand the predictors and mechanisms involved in the progress to a full psychotic episode. The aim of the current study was to provide an initial description and prevalence rates of specific content found within attenuated positive symptoms. The Content of Attenuated Positive Symptoms (CAPS) codebook was used by independent raters to determine the presence of content within a sample of written vignettes. Krippendorff's alpha was used to determine inter-rater reliability. Overall, the majority of items fell in or above an acceptable range of reliability. There was heterogeneity present in the types of content endorsed. However, the most commonly endorsed items included being perplexed by reality, increased hypervigilence, being gifted, hearing indistinct and distinct sounds, seeing figures or shadows, something touching the individual, and unpleasant smells. The use of the CAPS codebook is a reliable way to code the content of attenuated positive symptoms. Identifying and monitoring the presence of certain content may provide insight into the presence of other comorbid issues and the potential for future conversion.

Perceptual abnormalities in clinical high risk youth and the role of trauma, cannabis use and anxiety

“…CAPS codebook items are assigned a numeric code with items dichotomously coded as 0 (absent in the vignette) or 1 (present in the vignette). Using this coding scheme, a prior interrater reliability analysis (Marshall et al, 2014) reported higher than ‘acceptable’ (>70%) (Krippendorff, 2012) reliabilities for the majority (83.33%) of the CAPS items.…”

“…Symptom coding of case vignettes was completed by two raters, each of whom was trained on the CAPS codebook (Marshall et al, 2014). The content items of perceptual abnormalities were then used to generate the subtypes.…”

Examining associations between psychosis risk, social anhedonia, and performance of striatum-related behavioral tasks.

“…The SIPS was designed to detect attenuated positive symptoms (i.e., psychotic symptoms below the threshold of full-blown psychotic symptoms; Marshall et al, 2014; Miller et al, 2003). Its developers did not say it was designed to for use only in treatment seeking samples, but it has mostly been used in clinical populations at ultra-high risk for psychosis onset.…”

How Schizophrenia Develops: Cognitive and Brain Mechanisms Underlying Onset of Psychosis

“…This hypothesis is supported by evidence that more severe unusual ideas and beliefs at baseline predict the steeper rate of gray matter loss in superior and medial PFC bilaterally among CHR cases progressing to full psychosis [47] (Fig 2b). As such, disruptions in source memory may underlie the earliest appearing prodromal symptoms, which include perplexity or confusion about what is real versus imaginary, changes in the perception of time, and changes in the interpretation of events and experiences such that the familiar begins to feel strange, confusing, ominous, threatening, or otherwise to have special meaning [48]. Over time, more elaborate beliefs – such as alien control of thought, ideas of reference, and systemized persecutory delusions – may be built up as explanations of the faulty source attributions and generalized sense of foreboding, and skepticism in these explanations may erode as an increasing proportion of experience salient in memory is subject to source confusion.…”