Beta and Gamma Dynamics in Attentional Networks Predict Conscious Reports.

Conscious perception is preceded by distinct patterns of brain activity that depend on whether attention is oriented to the correct location or must be reoriented. Using magnetoencephalography, the study examined neural oscillations before near-threshold visual targets. Validly cued targets (67% of trials) were preceded by early beta-band activity in the right superior parietal lobule about 58 milliseconds after the cue. Invalidly cued targets that were reported were preceded by later beta activity in the right temporo-occipital region, theta-gamma phase-amplitude coupling in the right lateral visual cortex, and low gamma coherence between that region and the left temporoparietal junction.

Study at a glance

Abstract

What neural events precede conscious reports? Hemisphere-asymmetric attentional networks are causally related to conscious perception (Kaufmann et al., 2024; Bartolomeo et al., 2025), but their spectrotemporal dynamics remain unclear. Here, we used magnetoencephalography to examine brain oscillations occurring in human participants (male and female) before a near-threshold target during the cue-target period. In 67% of trials, a suprathreshold visual cue appeared near the target placeholder box, indicating that the target would appear at that location (valid condition). In the remaining 33% of trials, the target appeared at the opposite location (invalid condition). We analyzed brain oscillations, coherence, and theta-gamma phase-amplitude coupling (PAC) in 18 regions of interest involved in attention and perception (Martín-Signes et al., 2024). Results revealed the following: (1) Report of validly cued targets was preceded by early (∼58 ms postcue) beta-band activity in the right-hemisphere superior parietal lobule. (2) Report of invalidly cued targets was preceded by late (∼166 ms postcue) beta-band activity in the right temporo-occipital (TO) region, PAC in the right lateral visual cortex, and low gamma coherence between this region and the left temporoparietal junction. (3) Unreported invalidly cued targets were preceded by PAC in TO and by high gamma coherence between this region and the right middle frontal gyrus suggesting a pretarget bias. We show that conscious report is preceded by temporally dissociable, frequency-specific reconfigurations of right-lateralized attentional networks, with an early orienting window characterized by parietal beta-mediated activity and a later reorienting window by ventral beta and gamma activity.