New insights into conflict processing networks using MEG

25th February 2021

Jessica Rosenberg, Qunxi Dong, Esther Florin, Praveen Sripad, Frank Boers, Martina Reske, N. Jon Shah, Jürgen Dammers

The ability to suppress distracting information in order to focus on an actual goal is known as conflict processing or cognitive control and is strongly associated with an area of the brain known as the fronto-parietal attention network (FPAN).

Although various brain imaging methods have been used to investigate the underlying neurobiological brain activations that occur during conflict processing, none have identified the directional interconnections, their time courses, and activations at different frequency bands; knowledge of which would greatly improve our understanding of conditions characterised or associated with conflict resolution impairment e.g. schizophrenia and attention-deficit hyperactivity disorder. In response, this study uses an adaptation of the Simon task with magnetoencephalography (MEG) to provide detailed insight into the underlying neural mechanisms of the FPAN, with particular focus on its temporal characteristics and directional interconnections.

Based on the source-reconstructed MEG data, the cortical areas related to conflict processing were determined. For these brain regions, the spatio-temporal dynamics, including the directional interactions, were characterised at different frequency bands, enabling the identification of active interconnections during conflict processing when a neural reorganisation is required.

The findings show that, following stimulus onset, the middle frontal precentral cortex and superior parietal cortex were significantly activated during conflict processing in a time window of between 300 to 600ms. Important differences in causality were also found across frequency bands between processing of conflicting stimuli in the left as compared to the right visual hemifield. The exchange of information from and to the FPAN was most shown to be prominent in the beta band. Moreover, the anterior cingulate cortex and the anterior insula represented key areas for conflict monitoring, either by receiving input from other areas of the FPAN or by generating output themselves and the salience network was also indicated as being involved in processing conflict information.

In addition to providing detailed insight into conflict processing in the brain, the findings of this research also have strong implications for future research relating to distortions of the FPAN, and in research relating to mental illnesses such as schizophrenia and attention-deficit hyperactivity disorder.

Origional publication:

Conflict processing networks: A directional analysis of stimulus-response compatibilities using MEG