Theta-burst transcranial magnetic stimulation to the prefrontal cortex impairs metacognitive visual awareness

Rounis, Elisabeth; Maniscalco, Brian; Rothwell, John C.; Passingham, Richard E.; Lau, Hakwan

doi:10.1080/17588921003632529

Cited by 346 publications

(482 citation statements)

References 31 publications

Supporting

Mentioning

418

Contrasting

Unclassified

Order By: Relevance

“…However, a prediction can be ventured that subjects with lesions restricted to frontal damage would show an altered metacontrast function for visual awareness. Indeed, a temporary simulation of this condition by transcranial magnetic stimulation recently yielded just this result (29). It could be that other foci, perhaps also elsewhere in frontal cortex, would play a comparable role for each of the impairments of other sensory systems, as in "numbsight" and "deaf hearing.…”

Section: Discussionmentioning

confidence: 93%

Consciousness of the first order in blindsight

Sahraie

Hibbard

Trevethan³

et al. 2010

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

At suprathreshold levels, detection and awareness of visual stimuli are typically synonymous in nonclinical populations. But following postgeniculate lesions, some patients may perform above chance in forced-choice detection paradigms, while reporting not to see the visual events presented within their blind field. This phenomenon, termed "blindsight," is intriguing because it demonstrates a dissociation between detection and perception. It is possible, however, for a blindsight patient to have some "feeling" of the occurrence of an event without seeing per se. This is termed blindsight type II to distinguish it from the type I, defined as discrimination capability in the total absence of any acknowledged awareness. Here we report on a well-studied patient, D.B., whose blindsight capabilities have been previously documented. We have found that D.B. is capable of detecting visual patterns defined by changes in luminance (first-order gratings) and those defined by contrast modulation of textured patterns (textured gratings; second-order stimuli) while being aware of the former but reporting no awareness of the latter. We have systematically investigated the parameters that could lead to visual awareness of the patterns and show that mechanisms underlying the subjective reports of visual awareness rely primarily on low spatial frequency, first-order spatial components of the image.S ince the early reports in the 1970s of brain-damaged human subjects who are able to discriminate visual events in the absence of self-reported conscious awareness (1, 2), an obvious but difficult question has arisen as to what stimulus properties would drive visual awareness. In nonclinical populations, a number of paradigms have been developed to examine the prerequisites. For example, in attentional-blink paradigms (3), rapid serial visual presentation demonstrates that letters or words presented within a short temporal window following a task-relevant target may be degraded. As is well known, manipulating the functional significance of targets by using the participant's name (4) or emotional stimuli (5) modulates reported perception and discrimination of stimuli. More recently, the flash suppression technique in binocular rivalry, where one eye is presented with a rapid random sequence of abstract shapes while a specific stimulus is presented to the other eye (6), has been used to demonstrate that some classes of stimuli can break through and elicit awareness (7,8). Common among tasks presented to nonclinical subjects is the assumption that awareness of the stimuli and their discrimination, if not identical, cannot be dissociated from each other.The blindsight phenomenon in human subjects is unique: following visual cortical lesions, the detection and discrimination of stimulus features can occur in the absence of subjective awareness. For this reason, the research relies on "heroic" approaches such as forced-choice guessing (9). The reported awareness is then recorded using a commentary key paradigm on either a binary (10) or a mult...

show abstract

Section: Discussionmentioning

confidence: 93%

Consciousness of the first order in blindsight

Sahraie

Hibbard

Trevethan³

et al. 2010

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

show abstract

“…Moreover, Slachevsky et al (2001Slachevsky et al ( , 2003 have shown that lesion affecting the prefrontal cortex also affects awareness as well as the monitoring of actions or sensorymotor readjustments. Other studies showed that bilaterally depressed activity in the dorsolateral prefrontal cortex using transcranial magnetic stimulation, can affect metacognition but not task performance during a visual discrimination task (Rounis et al 2010;Turatto et al 2004). In this cross-sectional study, we cannot determine whether poor metacognition is a consequence or/and a cause of gambling behaviors.…”

Section: Discussionmentioning

confidence: 99%

Impaired Metacognitive Capacities in Individuals with Problem Gambling

et al. 2012

View full text Add to dashboard Cite

Impaired insight into behavior may be one of the clinical characteristics of pathological gambling. In the present study, we tested whether the capacity to evaluate accurately the quality of one's own decisions during a non-gambling task was impaired in problem gamblers. Twenty-five problem gamblers and 25 matched healthy participants performed an artificial grammar-learning paradigm, in which the quality of choice remains uncertain throughout the task. After each trial of this task, participants had to indicate how confident they were in the grammaticality judgements using a scale ranging from 1 (low confidence) to 7 (high confidence). Results showed that (i), problem gamblers' performance on the grammaticality test was lower than controls'; (ii) there was a significant correlation between grammaticality judgments and confidence for control participants, which indicates metacognitive insight and the presence of conscious knowledge; (iii) this correlation was not significant in problem gamblers, which suggests a disconnection between performance and confidence in this group. These findings suggest that problem gamblers are impaired in their metacognitive abilities on a non-gambling task, which suggests that compulsive gambling is associated with poor insight as a general factor. Clinical interventions tailored to improve metacognition in gambling could be a fruitful avenue of research in order to prevent pathological gambling.

show abstract

“…Dehaene and Changeux, 2011;Driver and Vuilleumier, 2001;Rees, 2013). Transcranial magnetic stimulation (TMS) inducing transient dysfunction in parietal or prefrontal areas can prevent conscious perception and even trigger sudden subjective disappearance of visual stimuli (Kanai et al, 2008;Beck et al, 2006;Carmel et al, 2010;Babiloni et al, 2007;Kihara et al, 2011), a reduction of subjective visibility (Rounis et al, 2010), or a hemineglect-like profile (Sack, 2010). Fronto-parietal networks have also been demonstrated to subserve executive control and working memory (Egner et al, 2008;Bressler and Menon, 2010;Menon, 2013;Rottschy et al, 2012Rottschy et al, , 2013, with prominent activations found in the right hemisphere (Hardwick et al, 2013).…”

Section: Introductionmentioning

confidence: 99%

Synchronization of fronto-parietal beta and theta networks as a signature of visual awareness in neglect

et al. 2017

View full text Add to dashboard Cite

The version presented here may differ from the published version or from the version of record. If you wish to cite this item you are advised to consult the publisher's version. Please see the repository url above for details on accessing the published version and note that access may require a subscription. In the neglect syndrome, the perceptual deficit for contra-lesional hemi-space is increasingly viewed as a dysfunction of fronto-parietal cortical networks, the disruption of which has been described in neuroanatomical and hemodynamic studies. Here we exploit the superior temporal resolution of electroencephalography (EEG) to study dynamic transient connectivity of fronto-parietal circuits at early stages of visual perception in neglect. As reflected by interregional phase synchronization in a full-field attention task, two functionally distinct frontoparietal networks, in beta (15-25 Hz) and theta (4-8 Hz) frequency bands, were related to stimulus discrimination within the first 200 ms of visual processing. Neglect pathology was specifically associated with significant suppressions of both beta and theta networks engaging right parietal regions. These connectivity abnormalities occurred in a pattern that was distinctly different from what was observed in right-hemisphere lesion patients without neglect. Also, both beta and theta abnormalities contributed additively to visual awareness decrease, quantified in the Behavioural Inattention Test. These results provide evidence for the impairment of fast dynamic fronto-parietal interactions during early stages of visual processing in neglect pathology. Also, they reveal that different modes of fronto-parietal dysfunction contribute independently to deficits in visual awareness at the behavioural level.

show abstract

Theta-burst transcranial magnetic stimulation to the prefrontal cortex impairs metacognitive visual awareness

Cited by 346 publications

References 31 publications

Consciousness of the first order in blindsight

Consciousness of the first order in blindsight

Impaired Metacognitive Capacities in Individuals with Problem Gambling

Synchronization of fronto-parietal beta and theta networks as a signature of visual awareness in neglect

Contact Info

Product

Resources

About