Investigating the neurobiology of schizophrenia and other major psychiatric disorders with Transcranial Magnetic Stimulation

The Current and Future Potential of Transcranial Magnetic Stimulation With Electroencephalography in Psychiatry

“…This hypothesis has also been supported by neurophysiological evidence indicating altered levels of GABAergic activity in SCZ. Reduced short interval cortical inhibition (SICI), a paired‐pulse TMS index for low‐threshold GABA‐A receptor‐mediated neurotransmission, is one of the most consistently replicated findings in SCZ research, spanning from the prodromal to active phase of the disorder and correlating with the severity of positive symptoms and cognitive deficits . Reduced GABA‐B receptor‐mediated inhibition through TMS measurements of LICI has also been documented in the DLPFC of SCZ patients .…”

“…It is characterized by a pattern of manic and depressive episodes, arising in pervasive changes in mood and cognitive deficits, such as impaired executive functions. BPD is thought to share similar neurophysiological features with MDD, such as altered DLPFC activity, and with SCZ, due to similar deficits in TMS measures of cortical inhibition . Recent research has focused on disrupted cortical neuroplasticity as a therapeutic target for treatment.…”

“…In addition to the generation of cortical oscillations, modulation of these oscillation bands is also essential for cortical function. Previous TMS studies had identified deficits of cortical inhibition in both patients with SCZ and BPD; however, it was unclear whether this would arise in generalized impairments in the inhibitory modulation of gamma oscillations. Using the LICI paradigm, which is linked to GABA‐B receptor activity, Farzan et al .…”

Transcranial magnetic stimulation for schizophrenia: potential and risks

“…In those studies, researchers applied TMS in combination with motor evoked potentials (TMS/MEPs) and high density electroencephalograms ( TMS/hd-EEG) [1] . The studies revealed significant impairments in cortical excitability, inhibition, and oscillatory activity, which are more prominent in the frontal brain areas, in patients suffering from schizophrenia compared to healthy controls [1] . Future TMS studies may help explain the underlying neurobiology of schizophrenia, and TMS may help monitor and perhaps further optimize the effectiveness of treatment interventions in patients with this disease.…”

“…Although the symptoms may be common, schizophrenia may have many different causes that are influenced by genetic and environmental factors, resulting in a very heterogenic population of patients [7] . The answers to the questions of how informative the TMS findings that have been collected on schizophrenia so far [1] with respect to those subtypes of patient groups with schizophrenia are and what those findings mean at the individual patient level (e.g. with respect to gender differences, interactions with individual pharmacological treatments, etc.)…”