When dissimilar images are presented to the two eyes, binocular rivalry (BR) occurs, and perception alternates spontaneously between the images. Although neural correlates of the oscillating perception during BR have been found in multiple sites along the visual pathway, the source of BR dynamics is unclear. Psychophysical and modeling studies suggest that both low- and high-level cortical processes underlie BR dynamics. Previous neuroimaging studies have demonstrated the involvement of high-level regions by showing that frontal and parietal cortices responded time locked (...) to spontaneous perceptual alternation in BR. However, a potential contribution of early visual areas to BR dynamics has been overlooked, because these areas also responded to the physical stimulus alternation mimicking BR. In the present study, instead of focusing on activity during perceptual switches, we highlighted brain activity during suppression periods to investigate a potential link between activity in human early visual areas and BR dynamics. We used a strong interocular suppression paradigm called continuous flash suppression to suppress and fluctuate the visibility of a probe stimulus and measured retinotopic responses to the onset of the invisible probe using functional MRI. There were ∼130-fold differences in the median suppression durations across 12 subjects. The individual differences in suppression durations could be predicted by the amplitudes of the retinotopic activity in extrastriate visual areas (V3 and V4v) evoked by the invisible probe. Weaker responses were associated with longer suppression durations. These results demonstrate that retinotopic representations in early visual areas play a role in the dynamics of perceptual alternations during BR. (shrink)

Most animals have mental states of one sort or another, but few species share our capacity for self-awareness. We are aware of our own mental states via introspection, and we are aware of the mental states of our fellow human beings on the basis of what they do and say. This chapter is not concerned with these traditional forms of mind-reading—forms whose origins predate the beginnings of recorded history—but with the prospects of a rather different and significantly more recent form (...) of ‘mind-reading’: the capacity to reliably ascribe mental states to a creature on the basis of information derived from information about their brain states. (shrink)

Macpherson (Nous 40(1):82–117, 2006) argues that the square/regular diamond figure threatens representationalism, construed as the theory which holds that the phenomenal character is explained by the nonconceptual content of experience. Her argument is the claim that representationalism is committed to the thesis that differences in the experience of ambiguous figures, the gestalt switch, should be explained by differences in the NCC of perception of these figures. However, with respect to the square/regular diamond and some other ambiguous figure representationalism fails to (...) offer a unified account of how representational content makes them ambiguous. In this paper, I aim, first, to offer a representationalist account of ambiguous figures and, second, to examine and rebut Macpherson’s arguments. My main point is that in each ambiguous figure Macpherson discusses there are differences in representational content that can explain differences in phenomenal character or content. The representational differences are due to the ways the Cartesian frame of reference in which perceptual content is always cast cuts the figure, underlying different properties of the figure with respect to the axes of the Cartesian frame of reference. (shrink)

An increasing number of studies indicate that virtues affect brain structure. These studies might shed new light on some neuroethical perspectives suggesting that our brain network activity determines the acquisition and permanence of virtues. According to these perspectives, virtuous behavior could be interpreted as the product of a brain mechanism supervised by genes and environment and not as the result of free choice. In this respect, the neural correlates of virtues would confirm the deterministic theory. In contrast, I maintain that (...) these findings do not undermine the role of willpower and freedom while reinforcing an interactionist view of free will. If virtues affect our neural system, then the predictability of the virtuous behavior follows. The likelihood of our future (moral) actions is primarily virtue-dependent; therefore, the acquired naturality of virtuous behavior is a source of predictable behavioral patterns outlining expected actions, which I propose to call Hypotheses of Action (HAs). However, the predictability of an action indicates its likeliness and not its certainty or necessity. The neural traces of virtues can be interpreted as major indicators of HAs. It is always possible for the agents to depart from their more likely, virtue-induced actions, but their deviations from the virtuous behavioral pattern are rare, as it is rare for the vicious/non-virtuous person to behave well systematically. This implies a reaffirmation of the notions of veto and consent as they provide a universal practical power affecting the subject’s use of moral virtues. (shrink)

Cerebral energy supply is insufficient to support continuous neuronal processing of the plethora of time-constant objects that we are aware of. As a result, the brain is forced to limit processing resources to (the most relevant) cases ofchange. The neuronally generated world is thus temporally discontinuous. This parallels the fact that, in all relevant microscopic fundamental equations of nature, temporalchangeplays a dominant role. When a scientist calculates a “solution” to such an equation, integration over time is an essential step. The (...) present Hypothesis expresses that the step from neuronal activity to phenomenal content of consciousness is reflective of a (phenomenal) “solution:” the main source of the incomprehensibility of consciousness is proposed to result from the introduction of phenomenal time-constant entities. These are “filled-in”viaintegration, even though neuronal data only exists forchangesto these entities. In this way, a temporally continuous picture of the world phenomenally appears. Qualia are “initial conditions,” which are required for integration and cannot be deduced frompresentdata. Phenomenal “identity” (vs. “high similarity”) is related to qualia.Inattentivevisual perception, which is only rarely investigated, offers insights into these relationships. Introspectively, unattended vision appears rich because percepts are cumulated over long time spans, whereas attentive perception relies purely onpresentneuronal signals. The present Hypothesis is that a brief neuronal activity cansignifylong-lasting and constant phenomenal content of consciousness. Experimental support is presented that comes from discrepancies between neuronal activity and perception: transient neuronal responses to sustained stimuli, “filling-in,” change blindness, identity vs. close resemblance. (shrink)

The goal of this study is to characterize observers’ abilities to detect gradual changes and to explore putative dissociations between conscious experience of change and behavioral adaptation to a changing stimulus. We developed a new experimental paradigm in which, on each trial, participants were shown a dot pattern on the screen. Next, the pattern disappeared and participants had to reproduce it. In some conditions, the target pattern was incrementally rotated over successive trials and participants were either informed or not of (...) this change. We analyzed both awareness of the changes and the dynamics of behavioral adaptation, in a way that makes it possible to assess both variability and accuracy as they change over time. Results indicate a dissociation between change awareness and behavioral adaptation to the changes, and support the notion that unconscious representations of visual stimuli are more precise and detailed than previously suggested. We discuss the implications of these results for theories of change detection. (shrink)

In recent years, neuroscience has begun to transform itself into a “big data” enterprise with the importation of computational and statistical techniques from machine learning and informatics. In addition to their translational applications such as brain-computer interfaces and early diagnosis of neuropathology, these tools promise to advance new solutions to longstanding theoretical quandaries. Here I critically assess whether these promises will pay off, focusing on the application of multivariate pattern analysis (MVPA) to the problem of reverse inference. I argue that (...) MVPA does not inherently provide a new answer to classical worries about reverse inference, and that the method faces pervasive interpretive problems of its own. Further, the epistemic setting of MVPA and other decoding methods contributes to a potentially worrisome shift towards prediction and away from explanation in fundamental neuroscience. (shrink)