Publications in English

Peer-reviewed papers

Are There Degrees of Self-Consciousness?  
Millière R.
Forthcoming in the Journal of Consciousness Studies

It is widely assumed that ordinary conscious experience involves some form of sense of self or consciousness of oneself. Moreover, this claim is often restricted to a “thin” or “minimal” notion of self-consciousness, or even “the simplest form of self-consciousness” (Blanke & Metzinger, 2009), as opposed to more sophisticated forms of self-consciousness which are not deemed ubiquitous in ordinary experience. These formulations suggest that self-consciousness comes in degrees, and that individual subjects may differ with respect to the degree of self-consciousness they exhibit at a given time. In this article, I critically examine this assumption. I consider what the claim that self-consciousness comes in degrees may mean, raise some challenges against the different versions of the claim, and conclude that none of them is both coherent and particularly plausible.

Psychedelics, Meditation and Self-Consciousness  
Millière R., Carhart-Harris R., Roseman L., Trautwein M. and Berkovich-Ohana A.
Frontiers in Psychology, 9, pp. 1-29 (doi: 10.3389/fpsyg.2018.01475).

In recent years, the scientific study of meditation and psychedelic drugs has seen remarkable developments. The increased focus on meditation in cognitive neuroscience has led to a cross-cultural classification of standard meditation styles validated by functional and structural neuroanatomical data. Meanwhile, the renaissance of psychedelic research has shed light on the neurophysiology of altered states of consciousness induced by classical hallucinogens, such as psilocybin and LSD, whose effects are mainly mediated by agonism of serotonin receptors. 

Few attempts have been made at bridging these two domains of inquiry, despite intriguing evidence of overlap between the phenomenology and neurophysiology of meditation practice and psychedelic states. In particular, many contemplative traditions explicitly aim at dissolving the sense of self by eliciting altered states of consciousness through meditation, while classical psychedelics are known to produce significant disruptions of self-consciousness, a phenomenon known as drug-induced ego dissolution. In this article, we discuss available evidence regarding convergences and differences between phenomenological and neurophysiological data on meditation practice and psychedelic drug-induced states, with a particular emphasis on alterations of self-experience.

While both meditation and psychedelics may disrupt self-consciousness and underlying neural processes, we emphasize that neither meditation nor psychedelic states can be conceived as simple, uniform categories. Moreover, we suggest that there are important phenomenological differences even between conscious states described as experiences of self-loss. As a result, we propose that self-consciousness may be best construed as a multidimensional construct, and that “self-loss”, far from being an unequivocal phenomenon, can take several forms. Indeed, various aspects of self-consciousness, including narrative aspects linked to autobiographical memory, self-related thoughts and mental time travel, and embodied aspects rooted in multisensory processes, may be differently affected by psychedelics and meditation practices.

Finally, we consider long-term outcomes of experiences of self-loss induced by meditation and psychedelics on individual traits and prosocial behavior. We call for caution regarding the problematic conflation of temporary states of self-loss with “selflessness” as a behavioral or social trait, although there is preliminary evidence that correlations between short-term experiences of self-loss and long-term trait alterations may exist.

There is converging evidence that high doses of hallucinogenic drugs can produce significant alterations of self-experience, described as the dissolution of the sense of self and the loss of boundaries between self and world. This article discusses the relevance of this phenomenon, known as “drug-induced ego dissolution" (DIED), for cognitive neuroscience, psychology and philosophy of mind.

Data from self-report questionnaires suggest that three neuropharmacological classes of drugs can induce ego dissolution: classical psychedelics, dissociative anesthetics and agonists of the kappa opioid receptor (KOR). While these substances act on different neurotransmitter receptors, they all produce strong subjective effects that can be compared to the symptoms of acute psychosis, including ego dissolution. It has been suggested that neuroimaging of DIED can indirectly shed light on the neural correlates of the self.

While this line of inquiry is promising, its results must be interpreted with caution. First, neural correlates of ego dissolution might reveal the necessary neurophysiological conditions for the maintenance of the sense of self, but it is more doubtful that this method can reveal its minimally sufficient conditions. Second, it is necessary to define the relevant notion of self at play in the phenomenon of DIED. This article suggests that DIED consists in the disruption of subpersonal processes underlying the “minimal” or “embodied” self, i.e., the basic experience of being a self rooted in multimodal integration of self-related stimuli. This hypothesis is consistent with Bayesian models of phenomenal selfhood, according to which the subjective structure of conscious experience ultimately results from the optimization of predictions in perception and action.

Finally, it is argued that DIED is also of particular interest for philosophy of mind. On the one hand, it challenges theories according to which consciousness always involves self-awareness. On the other hand, it suggests that ordinary conscious experience might involve a minimal kind of self-awareness rooted in multisensory processing, which is what appears to fade away during DIED.

Book chapters

Ingarden’s Combinatorial Analysis of The Realism-Idealism Controversy  
Millière R.
In S. Richard and O. Malherbe (Eds.), Form(s) and Modes of Being. The Ontology of Roman Ingarden, Bern and New York: Peter Lang, 2016 (penultimate draft).

The Controversy over the Existence of the World (henceforth Controversy) is the magnum opus of Polish philosopher Roman Ingarden. Despite the renewed interest for Ingarden’s pioneering ontological work whithin analytic philosophy, little attention has been dedicated to Controversy's main goal, clearly indicated by the very title of the book: finding a solution to the centuries-old philosophical controversy about the ontological status of the external world. 

There are at least three reasons for this relative indifference. First, even at the time when the book was published, the Controversy was no longer seen as a serious polemical topic, whether it was disqualified as an archaic metaphysical pseudo-problem, or taken to be the last remnant of an antiscientific approach to philosophy culminating in idealism and relativism. Second, Ingarden’s reasoning on the matter is highly complex, at times misleading, and even occasionally faulty. Finally, his analysis is not only incomplete – Controversy being unachieved – but also arguably aporetic. 

One may wonder, then, why it is still worth excavating this mammoth treatise to study an issue apparently no longer relevant to contemporary philosophy. Aside from historical and exegetical purposes, which are of course very interesting in their own right, Ingarden’s treatment of the Controversy remains one of the most detailed and ambitious ontological undertakings of the twentieth century. Not only does it lay out an incredibly detailed map of possible solutions to the Controversy, but it also tries to show why the latter is a genuine and fundamental problem that owes its hasty disqualification to various oversimplifications over the course of the history of philosophy. 

In this chapter, I first give an overview of Ingarden’s method, which relies mainly on a combinatorial analysis. Then, I summarize his examination of possible solutions to the Controversy, and determine which ones can be ruled out on ontological grounds. Finally, I explain why this ambitious project ultimately leads to a theoretical impasse, leaving Ingarden unable to come up with a definitive solution to the Controversy – regardless of the fact that the book is unachieved. I argue that his analysis of the problem yields a more modest but nonetheless valuable result.

Articles under review

Neural Correlates of The DMT Experience   
Timmermann C., Roseman L., Schartner M., Millière R., Williams L., Erritzoe D., et al.

N,N-Dimethyltryptamine (DMT) is a psychedelic compound, which produces exceptionally vivid experiences and unusual subjective effects. Here we sought to investigate the effects of intravenous DMT administration on the electroencephalogram (EEG)-recorded rhythmic activity and cortical signal complexity, both measures which have shown a close relationship with states and levels of consciousness in humans. We also aimed to establish the neuronal response behind the dynamic shifts in consciousness induced by the intense, but short-lived, effects of DMT using a neurophenomenological approach. Compared to placebo, DMT markedly reduced oscillatory power in most frequency bands analyzed and significantly increased cortical signal complexity. Furthermore, we report for the first time a close relationship between minute-by-minute fluctuations of the subjective psychedelic state with neuronal changes in cortical rhythmic activity and signal complexity, as well as a temporal relationship between these EEG measures and three dimensions of subjective experience which were altered by DMT. These results highlight a fundamental role for reduced rhythmic activity and increased cortical signal complexity in the neuronal correlates of the subjective effects of DMT and more broadly emphasize the use of short-acting psychedelics for the study of temporal shifts of conscious experience.

Note on the nature of my participation to this study: I have conducted post-hoc micro-phenomenological interviews with each subject after the administration of intraveinous DMT. The interview data was time-locked to the objective chronology of the experience (with a temporal resolution of 1 minute intervals), through a novel experimental design involving the spontaneous recall of minute-by-minute intensity ratings in post-hoc interviews. I subsequently analysed the interview data and plotted the evolution of bodily effects, visual effects and emotional/metacognitive response across time, both within and between subjects. This allowed us to correlate specific phases of the experience for specific dimensions (visual, bodily or emotional/metacognitive) with time-specific EEG data. The results demonstrate that temporally fine-grained neurophenomenological correlations can be obtained in drug research, and in consciousness research at large. This cannot be achieved with self-report questionnaires. For more information, see the standalone paper Neurophenomenology of DMT-induced states below, as well as the Experiments page.

Work in progress

The Varieties of Selflessness  
Millière R.

Many authors are sympathetic to the claim that there is a sense of self in ordinary experience. One way to vindicate this claim is to look for phenomenal contrast cases, i.e. cases of "selfless" conscious states lacking self-consciousness, in order to compare them to ordinary experience. However, while many altered states of consciousness have been described as disruptions of self-consciousness, there is no real agreement on what really counts as a conscious state lacking self-consciousness altogether. 

In this paper, I argue for a pluralist view of self-consciousness, according to which there are different ways in which a subject may be self-conscious. I suggest that each of these modalities of self-consciousness can be isolated through the method of phenomenal contrast, by comparing a number of relevant altered states of consciousness. These are instances of partially selfless states, namely states which lack some form(s) of self-consciousness, but not all. I also argue that there are instances of totally selfless states, namely conscious lacking any kind of self-consciousness – in certain forms of meditation, drug-induced experiences and perhaps dreamless sleep episodes. The upshot is that self-consciousness is a multidimensional construct, and can be disrupted in different ways and to different degrees; consequently, selflessness also comes in different varieties, although there is such a thing as total selflessness.

Neurophenomenology of DMT-induced States  
Millière R.
and Timmermann C.

In this paper, we expand on the results of the experiment described in “Neural correlates of the DMT experience” (see above). We analyse the interview data more in-depth, both through qualitative analysis, and through quantitative analysis (using Natural Language Processing techniques). We also present and discuss novel neurophenomnological correlations on the basis of this analysis, which a particular focus on the temporal structure of the experience.

In this paper, we present a new quantitative analysis of the largest corpus of narrative reports of drug-induced states (more than 15,000 reports in total). Using Natural Language Processing algorithms, we map out the state-space of subjective effects produced by hundreds of psychoactive drugs, and analyse specific categories of effects (bodily effects, visual effects, auditory effects, emotional effects, cognitive effects, effects on self-consciousness). 

We argue that our data is of particular interest for consciousness research, as they can not only enrich our understanding of the effects of well-known psychoactive drugs (beyond the limitations of questionnaires), but also shed light on novel drugs that can be used in controlled environements to investigate the neural correlates of specific conscious contents.  

Publications in French

Peer-reviewed papers

Is Life Absurd?  
Millière, R.
Klesis, 41 (special issue on the work of Thomas Nagel) , pp. 248-283, 2018  (open access).

This paper was written for a special issue of Klesis dedicated to the work of Thomas Nagel. In the paper, I critically examine Nagel’s work on the absurdity of life, and compare it to Albert Camus’ perspective from The Myth of Sisyphus. I distinguish four different versions of the claim that life is absurd, two found in Camus’ work, and two found in Nagel’s work. They all agree on one point: the absurdity of life stems from a form of cognitive dissonance. I examine each of these claims in detail, and argue that although they may seem intuitively compelling, none of them is well suported upon further analysis. I conclude that there is no good reason to believe that life is absurd after all.

Autoscopic Phenomena, Full-Body Illusions and Bodily Self-Consciousness   
Millière R.
Intellectica, 1:67, pp. 165-198, 2017.

During some autoscopic phenomena and full-body illusions using experimental setups, patients or healthy individuals can undergo altered states of consciousness in which three fundamental aspects of ordinary experience can be dissociated. These three aspects, which share a seemingly “self-referential” character, are self-identification to a body, self-location in space and the experienced direction of the visuospatial perspective. 

This article analyses clinical and experimental data regarding autoscopic phenomena and autoscopic illusions, as well as the mechanisms of multisensory integration underlying the “self-referential” aspects they alter. Furthermore, the article draws from these data to propose the hypothesis that self-location in space, whether it is body location or first-person perspective location, may be necessary condition of the experience of being a self perceiving the world from a certain standpoint. A discussion of philosophical debates about self-location, bodily awareness and self-consciousness is outlined in light of this hypothesis.

Millière R.
L’Encyclopédie Philosophique, 2016 (peer-reviewed online encyclopedia of philosophy)

This entry was written for a new peer-reviewed online encyclopedia of philosophy in French (created on the model of the Stanford Encyclopedia of Philosophy). It reviews discussions on the notion of subjectivity in contemporary philosophy of mind.

Book chapters

A Criticism of Apodictic Realism  
Millière R.
In E. During and E. Alloa (Eds.), Choses en soi. Comment être réaliste, Paris: PUF, 2018

In this short invited contribution, adapted from a talk given at the 'Things in Themselves’ symposium in Paris in 2016, I discuss the question of whether it is possible to demonstrate metaphysical realism, the claim that there exists mind-independent things. I criticise recent claims regarding the possibility of such demonstration within the so-called “New Realism” movement. Drawing on parallel discussions in analytic metaphysics, I argue that metaphysical realism should rather be defended on the basis of an abductive argument.