PT  - JOURNAL ARTICLE
AU  - Daniel Bor
AU  - David J. Schwartzman
AU  - Adam B. Barrett
AU  - Anil K. Seth
TI  - Theta-burst Transcranial Magnetic Stimulation to the Prefrontal or Parietal Cortex Does Not Impair Metacognitive Visual Awareness
AID  - 10.1101/058032
DP  - 2016 Jan 01
TA  - bioRxiv
PG  - 058032
4099  - http://biorxiv.org/content/early/2016/06/09/058032.short
4100  - http://biorxiv.org/content/early/2016/06/09/058032.full
AB  - Neuroimaging studies commonly associate dorsolateral prefrontal cortex (DLPFC) and posterior parietal cortex with conscious perception. However, such studies only investigate correlation, rather than causation. In addition, many studies conflate objective performance with subjective awareness. In an influential recent paper, Rounis and colleagues addressed these issues by showing that theta burst transcranial magnetic stimulation (tbs-TMS) applied to the DLPFC impaired metacognitive (subjective) awareness for a perceptual task, while objective performance was kept constant. We attempted to replicate this finding, with minor modifications, including an active tbs-TMS control site. Using a between-subjects design for both DLPFC and posterior parietal cortices, we found no evidence of a tbs-TMS-induced metacognitive impairment. In a second experiment, we devised a highly rigorous within-subjects tbs-TMS design for DLPFC, but again failed to find any evidence of metacognitive impairment. One crucial difference between ourresults and the Rounis study is our strict exclusion of data deemed unsuitable for a signal detection theory analysis. Indeed, when we included thisunstable data, a significant, though invalid, metacognitive impairment wasfound. These results cast doubt on previous findings relating metacognitive awareness to DLPFC, and inform the current debate concerning whether or not prefrontal regions are preferentially implicated in conscious perception.