A recent study suggests flash electroretinography (fERG) can help to predict the onset of schizophrenia by identifying retinal anomalies in patients.

A team of researchers recorded photopic- and scotopic-adapted fERG data from 25 schizophrenia patients and 25 healthy control subjects to monitor retinal cell function. They sought to determine whether past key discoveries on abnormal photoreceptor and bipolar cell signaling could be replicated and if schizophrenia-related changes in the fERG could be detected using a portable handheld ERG device.

For the first time, the team also examined retinal ganglion cell functioning using the photopic negative response of the fERG and measured schizophrenia patient responsiveness to a flickering stimulus as an additional method to isolate cone photoreceptor function.

In both photopic and scotopic conditions, the researchers found evidence to support earlier studies and discovered that schizophrenia patients demonstrated “weakened photoreceptor and bipolar cell activations that were most pronounced in response to the most intense stimuli.”

The schizophrenia group also displayed “a reduced cone response to a flicker stimulus and attenuation in ganglion cell activity,” indicating that fERG can also recognize retinal ganglion function abnormality, the authors wrote. These anomalies can be detected using a portable testing device, opening up the possibility for more routine ERG testing to identify signs of schizophrenia in patients.