Focusing on schizotypy may allow for some of the mechanisms to be disentangled through more detailed investigation without clinical complications such as medications and contact time in the clinic.
Other treatments, including noninvasive stimulation approaches (e.g., transcranial direct current stimulation: tDCS; transcranial magnetic stimulation: TMS), report improvements in sensory and cognitive markers, and reduce symptoms (reviewed in (Berryhill & Martin, 2018). For example, anodal tDCS improved pitch MMN amplitude and 2-back WM performance in people with schizophrenia (Impey et al., 2017). A separate study reported improved auditory P50 ERP response and reduced auditory hallucinations after anodal tDCS (Kim et al., 2018). In treatment resistant individuals with schizophrenia, a TMS protocol (intermittent theta burst stimulation) targeting left PFC improved visual WM ability and reduced symptoms (Wang et al., 2022). However, a recent meta-analysis evaluating findings from TMS and tDCS approaches reports no collective benefit across 22 studies (Sloan et al., 2021). Early-stage neurostimulation findings show promise, in terms of behavior and normalized biomarkers. However, small sample sizes, brief protocols, and a variable clinical population contribute to heterogeneous outcomes and a need for optimization. It is also unclear how stimulation methods would impact a less symptomatic population, particularly if the biomarkers in schizotypy are less pronounced than they are in diagnosed individuals.

Can Biomarkers be Used to Predict Schizophrenia Onset?

When assessing biomarkers of symptom severity, there is a burgeoning question as to whether some of the biomarkers already discussed here can be used to predict the onset of schizophrenia.