New Research: Cognitive Impairments in the First-Episode Schizophrenia Spectrum
For individuals with schizophrenia, impairment in the ability to selectively focus attention on some environmental stimuli while ignoring others is associated with worse symptoms and poor functional outcomes. Moreover, these cognitive impairments are largely resistant to treatment through medication.
To improve understanding of how dysfunction in the neural selective attention system contributes to these cognitive impairments, Pitt Psychiatry researchers Alfredo Sklar, MD, PhD (postdoctoral scholar); Brian Coffman, PhD (Research Instructor in Psychiatry); and Dean Salisbury, PhD (Professor of Psychiatry), investigated functioning of the fronto-parietal attention network during cue presentation on a visual search task. Because attention deficits are present early in the course of the illness, the investigators focused on the fronto-parietal attention network’s relationship to the implementation of attention in first-episode psychosis. The study was recently published in the Journal of Psychiatric Research.
Seventy-six study participants, 38 individuals with new-onset symptoms of psychosis and 38 individuals without psychotic symptoms, participated in a cued attention task while brain activity was measured across bilateral fronto-parietal attention network regions using magnetoencephalography. Those data were projected onto structural magnetic resonance imaging scans.
“The fronto-parietal attention network is a well-studied attention network that facilitates the control of coherent, goal-directed behaviors in healthy adults. Our approach allowed us to examine the neural sources of impaired cognitive control and their association with symptoms among individuals during their first psychotic episode with a high degree of anatomic precision,” said Dr. Sklar, the study’s first author.
Study participants with first-episode schizophrenia exhibited greater activity in the right hemisphere inferior frontal gyrus despite worse performance on the task relative to the comparison group. Among the first-episode schizophrenia group, however, stronger activity within right hemisphere frontal eye fields and inferior frontal gyrus was associated with faster responses. Stronger right intraparietal sulcus and left inferior frontal gyrus activity in patients was also associated with reduced negative symptoms and improved community functioning, respectively.
“These findings suggest that individuals with psychosis, even at the onset of the disease, have to use more brain resources to focus their attention and accomplish even simple tasks. New treatments using brain stimulation targeting the frontal-parietal attention network may provide relief from this dysfunction and related disability,” said senior author Dr. Salisbury.
Fronto-Parietal Network Function During Cued Visual Search in the First-Episode Schizophrenia Spectrum
Sklar AL, Coffman BA, Salisbury DF
Journal of Psychiatric Research, Volume 141, 2021, Pages 339-345, https://doi.org/10.1016/j.jpsychires.2021.07.014