To understand schizophrenia, a linking hypothesis is needed that shows how brain mechanisms lead to behavioral functions in normals, and also how breakdowns in these mechanisms lead to behavioral symptoms of schizophrenia. Such a linking hypothesis is now available that complements the discussion offered by Phillips & Silverstein (P&S).

The Phillips & Silverstein model of NMDA-mediated coordination deficits provides a useful heuristic for the study of schizophrenic cognition. However, the model does not specifically account for the development of schizophrenia-spectrum disorders. The P&S model is compared to Meehl's seminal model of schizotaxia, schizotypy, and schizophrenia, as well as the model of schizophrenic cognitive dysfunction posited by McCarley and colleagues.

It is always risky to make sweeping statements about the development of philosophy, but if one were nevertheless asked to describe 20th century philosophy in broad strokes, one noteworthy feature might be the following: Whereas important figures at the beginning of the century, figures such as Frege and Husserl, were very explicit in their rejection of naturalism (both are known for their rejection of the attempt to naturalize the laws of logic, i.e., for their criticism of psychologism), the situation has (...) changed considerably. Today many philosophers – not the least within analytical philosophy – would subscribe to some form of naturalism. In fact, naturalism is seen by many as the default metaphysical position. If you don’t subscribe to naturalism you must be subscribing to some form of Cartesian substance dualism. Thus, whereas 20 or 30 years ago one might have been inclined to characterize the development of 20th century philosophy in terms of a linguistic turn, a turn from a philosophy of subjectivity to a philosophy of language, it might today be more apt to describe the development in terms of a turn from anti-naturalism to naturalism. (shrink)

The recent move to naturalize phenomenology through a mathematical protocol is a significant advance in consciousness research. It enables a new and fruitful level of dialogue between the cognitive sciences and phenomenology of such a nuanced kind that it also prompts advancement in our phenomenological analyses. But precisely what is going on at this point of ‘dialogue’ between phenomenological descriptions and mathematical algorithms, the latter of which are based on dynamical systems theory? It will be shown that what is happening (...) is something more than a mere ‘passing of the baton’ from phenomenology to mathematics. For this sophisticated naturalization to prove a worthy endeavour it must produce more than just correlation, it must prove some form of interrelation to the extent that phenomenology is deterministic. But such interrelational and deterministic requirements are the start of a slippery slope, and it will be argued that this slope only loses more friction once a further demand of formal and precise descriptions is made of phenomenology. Such deterministic and formally precise demands misconstrue phenomenology’s ideal goal of a unification of genuine/originary reason and truth. Not a deductive and definitive discipline, phenomenology is rather from the outset descriptive and critical. Phenomenology’s descriptive beginnings will thus be employed as an essential barrier to the naturalization of phenomenology. (shrink)

_sciousness called ‘neurophenomenology’ (Varela 1996) and illustrates it with a_ _recent pilot study (Lutz et al., 2002). At a theoretical level, neurophenomenology_ _pursues an embodied and large-scale dynamical approach to the_ _neurophysiology of consciousness (Varela 1995; Thompson and Varela 2001;_ _Varela and Thompson 2003). At a methodological level, the neurophenomeno-_ _logical strategy is to make rigorous and extensive use of first-person data about_ _subjective experience as a heuristic to describe and quantify the large-scale_ _neurodynamics of consciousness (Lutz 2002). The paper (...) foocuses on_ _neurophenomenology in relation to three challenging methodological issues_ _about incorporating first-person data into cognitive neuroscience: (i) first-person_ _reports can be biased or inaccurate; (ii) the process of generating first-person_ _reports about an experience can modify that experience; and (iii) there is an ‘ex-_ _planatory gap’ in our understanding of how to relate first-person, phenomeno-_ _logical data to third-person, biobehavioural data._. (shrink)

• An adequate conceptual framework is still needed to account for phenomena that (i) have a first-person, subjective-experiential or phenomenal character; (ii) are (usually) reportable and describable (in humans); and (iii) are neurobiologically realized.2 • The conscious subject plays an unavoidable epistemological role in characterizing the explanadum of consciousness through first-person descriptive reports. The experimentalist is then able to link first-person data and third-person data. Yet the generation of first-person data raises difficult epistemological issues about the relation of second-order awareness (...) or meta-awareness to first-order experience (e.g. (shrink)

This article presents an interview method which enables us to bring a person, who may not even have been trained, to become aware of his or her subjective experience, and describe it with great precision. It is focused on the difficulties of becoming aware of one’s subjective experience and describing it, and on the processes used by this interview technique to overcome each of these difficulties. The article ends with a discussion of the criteria governing the validity of the descriptions (...) obtained, and then with a brief review of the functions of these descriptions. (shrink)

Subliminal perception (SP) is today considered a well-supported theory stating that perception can occur without conscious awareness and have a significant impact on later behaviour and thought. In this article, we first present and discuss different approaches to the study of SP. In doing this, we claim that most approaches are based on a dichotomic measure of awareness. Drawing upon recent advances and discussions in the study of introspection and phenomenological psychology, we argue for both the possibility and necessity of (...) using an elaborated measure of subjective states. In the second part of the article, we present findings where these considerations are implemented in an empirical study. The results and implications are discussed in detail, both with reference to SP, and in relation to the more general problem of using elaborate introspective reports as data in relation to studies of cognition. (shrink)

A theory of cognition and an interdisciplinary research program so-called enactivism put forward by Varela, Thompson, and Rosch since their book titled: “The Embodied Mind: Cognitive Science and Human Experience had been published in 1991. The theory and research program proposed in this book can be explicated in terms of eight significant themes including autopoiesis, sense-making, emergence, experience, embodied mind, embedded mind, enacted mind and the extended mind. This paper is an interpretation of the theory of enaction as a platform (...) to educational research methodological reform. So it is argued that the non-reductionistic enactive approach is the promising arena for addressing educational research methodology so that circulation between first- and third-personal phenomena makes sense across a range of objective and subjective issues that mixed methodologists want to deal. (shrink)

Whereas 20 or 30 years ago one might have been inclined to characterize the development of 20th century philosophy in terms of a linguistic turn, a turn from a philosophy of subjectivity to a philosophy of language, it might today be more apt to describe the development in terms of a turn from anti-naturalism to naturalism. But insofar as naturalists consider the scientific account of reality authoritative, a commitment to naturalism is bound to put pressure on the idea that philosophy (...) can make a distinct and autonomous contribution to the study of reality. In the following, I will discuss the question of how phenomenology ought to respond to this challenge. What sense can we make of recent proposals to naturalize phenomenology? (shrink)

This paper takes a new look at an old question: what is the human self? It offers a proposal for theorizing the self from an enactive perspective as an autonomous system that is constituted through interpersonal relations. It addresses a prevalent issue in the philosophy of cognitive science: the body-social problem. Embodied and social approaches to cognitive identity are in mutual tension. On the one hand, embodied cognitive science risks a new form of methodological individualism, implying a dichotomy not between (...) the outside world of objects and the brain-bound individual but rather between body-bound individuals and the outside social world. On the other hand, approaches that emphasize the constitutive relevance of social interaction processes for cognitive identity run the risk of losing the individual in the interaction dynamics and of downplaying the role of embodiment. This paper adopts a middle way and outlines an enactive approach to individuation that is neither individualistic nor disembodied but integrates both approaches. Elaborating on Jonas’ notion of needful freedom it outlines an enactive proposal to understanding the self as co-generated in interactions and relations with others. I argue that the human self is a social existence that is organized in terms of a back and forth between social distinction and participation processes. On this view, the body, rather than being identical with the social self, becomes its mediator. (shrink)

This paper aims to address the relevance of the natural sciences for transcendental phenomenology, that is, the issue of naturalism. The first section distinguishes three varieties of naturalism and corresponding forms of naturalization: an ontological one, a methodological one, and an epistemological one. In light of these distinctions, in the second section, I examine the main projects aiming to “naturalize phenomenology”: neurophenomenology, front-loaded phenomenology, and formalized approaches to phenomenology. The third section then considers the commitments of Husserl’s transcendental phenomenology with (...) respect to the three varieties of naturalism previously discussed. I argue that Husserl rejected strong and weak forms of epistemological naturalism, strong methodological naturalism, and ontological naturalism. The fourth section presents the argument that Husserl endorsed a weak, conditional form of methodological naturalism. This point is illustrated with Husserl’s proposal of “somatology,” a natural science apt to study the corporeality of the lived body. The final section addresses the complementarity and respective limits of the transcendental phenomenological and the natural scientific frameworks. I argue that, on Husserl’s account, the function of transcendental phenomenology with respect to the natural sciences is to provide them with an epistemological foundation and an ontological clarification. I suggest that certain natural sciences can be understood, within the transcendental phenomenological framework, as “sciences of constitution,” that is, as sciences investigating the contribution of real structures acting as conditions of possibility for the occurrence of certain kinds of comprehensive unities in lived experience. (shrink)

It is now conventional wisdom that conscious experience — or in Nagel’s canonical characterization, “what it is like to be” for an organism — is what makes the mind-body problem so intractable. By the same token, our current conceptions of the mind-body relation are inadequate and some conceptual development is urgently needed. Our overall aim in this paper is to make some progress towards that conceptual development. We first examine a currently neglected, yet fundamental aspect of consciousness. This aspect is (...) the spontaneity of consciousness, by which we mean its inner plasticity and inner purposiveness. We then sketch a “neurophenomenological” framework for thinking about the relationship between the spontaneity of consciousness and dynamic patterns of brain activity as studied in cognitive neuroscience. We conclude by proposing that the conscious mentality of sentient organisms or animals is active and dynamic, and that this “enactive” conception of consciousness can help us to move beyond the classical dichotomy between materialism and dualism. (shrink)

Questions about phenomenology’s role in non-philosophical disciplines gained renewed attention. While we claim that phenomenology makes indispensable, unique contributions to different domains of scientific practice such as concept formation, experimental design, and data collection, we also contend that when it comes to explanation, phenomenological approaches face a dilemma. Either phenomenological attempts to explain conscious phenomena do not satisfy a central constraint on explanations, i.e. the asymmetry between explanans and explanandum, or they satisfy this explanatory asymmetry only by largely merging with (...) non-phenomenological explanation types. The consequence of this dilemma is that insofar as phenomenological approaches are explanatory, they do not provide an own type of explanation. We substantiate our two claims by offering three case studies of phenomenologically inspired experiments in cognitive science. Each case study points out a specific phenomenological contribution to experimental practice while also illustrating how phenomenological approaches face the explanatory dilemma we outline. (shrink)

When putting semiotics and phenomenology in juxtaposition, the first task necessarily is to find out what a study of meaning, conceiving of itself as an empirical science, has to do with a philosophical school, the business of which it is to secure the epistemological foundations of all the sciences (broadly understood). Our answer, in short (but we will go at some length to show it), is that since all results of phenomenology also count as contributions to phenomenological psychology, the phenomenological (...) method constitutes a part of the panoply of methods offered to semiotics. Our second task will be to review the fragmentary semiotics proposed, originally employing that term, by Edmund Husserl, to gauge its value for contemporary semiotics. Since our investigation of Husserl’s semiotics will demonstrate that it sometimes concerns the sign in a narrow sense, and sometimes broadens up to a study of meaning in general, our third and final task, in this paper, will be to consider a proposal made by a close follower of Husserl, Alfred Schütz, whose idea of a system of relevancies, wedded to Husserl’s notion of sedimentation, might be amended when considered in connection with Umberto Eco’s idea of the encyclopaedia. (shrink)

Since the end of the last century, there has been several ambitious attempts to naturalize Husserlian phenomenology by way of mathematization. To justify themselves in view of Husserl’s adamant antinaturalism, many of these attempts appeal to the new physico-mathematical tools that were unknown in Husserl’s time and thus allegedly make his position outdated. This paper critically addresses these mathematization proposals and aims to show that Husserl had, in fact, sufficiently good arguments that make his antinaturalistic position sound even today. The (...) starting point of the discussion presented in this paper is the mathematization project introduced by Jean-Michel Roy, Jean Petitot, Bernard Pachoud, and Francisco Varela in their introduction to the book Naturalizing Phenomenology. This proposal was followed by a number of critiques but also by several alternative naturalization attempts clearly inspired by Roy et al.’s ambitious project. The review of some of Husserl’s important arguments often overlooked or misinterpreted by both the naturalization advocates and their critics leads the author of the paper to the twofold conclusion which, on the one hand, explores the deeper reasons for the impossibility of a physical and mathematical treatment of phenomenology, on the other hand, clarifies the sense in which such treatments are possible, namely by way of restriction of the variety of experiential aspects that undergo naturalization and substitution of the aspects amenable to the direct mathematization for the directly unmathematizable ones. In the fourth section of this paper, the author attempts to demonstrate that, contrary to widespread belief, Husserl’s arguments are not obsolete by the standards of the contemporary physico-mathematical approaches employed in the mathematization of phenomenology and indeed stand the test of time. (shrink)

Blanco, Carlos. Historia de la neurociencia: el conocimiento del cerebro y la mente desde una perspectiva inter-disciplinar. Madrid: Biblioteca Nueva, 2014. 296 pp.

There is a long-standing tradition of questioning the viability and scientificity of first-person methods. Husserlian reflective methodology, in particular, has been challenged on the basis of its perceived inability to meet the standards of objectivity and reliability, leading to what has been called “phenomenological skepticism” ( Roy, 2007 ). In this article, I reassess this line of objection by outlining Daniel C. Dennett’s empirically driven skepticism and reconstructing his methodological arguments against Husserlian phenomenology. His ensuing phenomenological skepticism is divided into (...) strong skepticism and categorical and gradual versions of weak skepticism. Both strands of Dennett’s criticism are then countered by analyzing the key components of Husserl’s method of phenomenological reflection: epoché and transcendental reduction, intentional analysis, eidetic variation, and intersubjective validation. Laying out the basic features of phenomenological reflection serves two purposes. First, it undermines Dennett’s methodological arguments, which are based on the unfounded assumptions that Husserl is committed to introspection, methodological solipsism, the first-person-plural presumption, and the lone-wolf approach. Second, it shows how Husserl’s own methodology can alleviate the more justified empirical worries concerning overinterpretation, underdescription, and disagreement. Finally, I argue that gradual weak skepticism is the only plausible form of phenomenological skepticism and conclude that Husserlian methodology is well-equipped to combat it. (shrink)

In everyday life, situations in which we act adequately yet entirely without deliberation are ubiquitous. We use the term “situated normativity” for the normative aspect of embodied cognition in skillful action. Wittgenstein’s notion of “directed discontent” refers to a context-sensitive reaction of appreciation in skillful action. Extending this notion from the domain of expertise to that of adequate everyday action, we examine phenomenologically the question of what happens when skilled individuals act correctly with instinctive ease. This question invites exploratory contributions (...) from a variety of perspectives complementary to the philosophical/ phenomenological one, including cognitive neuroscience, neurodynamics and psychology. Along such lines we try to make the normative aspect of adequate immediate action better accessible to empirical research. After introducing the idea that “valence” is a forerunner of directed discontent, we propose to make progress on this by first pursuing a more restricted exploratory question, namely, ‘what happens in the first few hundred milliseconds of the development of directed discontent?’. (shrink)

Phillips & Silverstein's focus on schizophrenia as a failure of “cognitive coordination” is welcome. They note that a simple hypothesis of reduced Gamma synchronisation subserving impaired coordination does not fully account for recent observations. We suggest that schizophrenia reflects a dynamic compensation to a core deficit of coordination, expressed either as hyper- or hyposynchronisation, with neurotransmitter systems and arousal as modulatory mechanisms.

Connectionist models aiming to reveal the mechanisms of atypical development must in their undamaged form constitute plausible models of normal development and follow a developmental trajectory that matches empirical data. Constructivist models that adapt their structure to the learning task satisfy this demand. They are therefore more informative in the study of atypical development than the static models employed by Thomas & Karmiloff-Smith (T&K-S).

It is often assumed that similar domain-specific behavioural impairments found in cases of adult brain damage and developmental disorders correspond to similar underlying causes, and can serve as convergent evidence for the modular structure of the normal adult cognitive system. We argue that this correspondence is contingent on an unsupported assumption that atypical development can produce selective deficits while the rest of the system develops normally (Residual Normality), and that this assumption tends to bias data collection in the field. Based (...) on a review of connectionist models of acquired and developmental disorders in the domains of reading and past tense, as well as on new simulations, we explore the computational viability of Residual Normality and the potential role of development in producing behavioural deficits. Simulations demonstrate that damage to a developmental model can produce very different effects depending on whether it occurs prior to or following the training process. Because developmental disorders typically involve damage prior to learning, we conclude that the developmental process is a key component of the explanation of endstate impairments in such disorders. Further simulations demonstrate that in simple connectionist learning systems, the assumption of Residual Normality is undermined by processes of compensation or alteration elsewhere in the system. We outline the precise computational conditions required for Residual Normality to hold in development, and suggest that in many cases it is an unlikely hypothesis. We conclude that in developmental disorders, inferences from behavioural deficits to underlying structure crucially depend on developmental conditions, and that the process of ontogenetic development cannot be ignored in constructing models of developmental disorders. Key Words: Acquired and developmental disorders; connectionist models; modularity; past tense; reading. (shrink)

Phillips & Silverstein's ambitious link between receptor abnormalities and the symptoms of schizophrenia involves a certain amount of fuzziness: No detailed mechanism is suggested through which the proposed abnormality would lead to psychological traits. We propose that detailed simulation of brain regions, using model neural networks, can aid in understanding the relation between biological abnormality and psychological dysfunction in schizophrenia.

Although interesting, the hypotheses proposed by Phillips & Silverstein lack unifying structure both in specific mechanisms and in cited evidence. They provide little to support the notion that low-level sensory processing and high-level cognitive coordination share dynamic grouping by synchrony as a common processing mechanism. We suggest that more realistic large-scale modeling at multiple levels is needed to address these issues.

In chronic schizophrenic patients with both positive and negative symptoms (see Table 1), interhemispheric connections at the high frequency beta2-rhythm are absent during cognitive tasks, in contrast to normal controls, who have many interhemispheric connections at this frequency in the same situation. Connectivity is a fundamental brain feature, evidently greatly promoted by the NMDA system. It is a more reliable measure of brain function than the spectral power of this rhythm.

Impairments in cognitive coordination in schizophrenia are supported by phenomenological data that suggest deficits in the processing of visual context. Although the target article is sympathetic to such a phenomenological perspective, we argue that the relevance of phenomenological data for a wider understanding of consciousness in schizophrenia is not sufficiently addressed by the authors.

Phillips & Silverstein argue that schizophrenia is a result of a deficit of the contextual coordination of neuronal responses. The authors propose that NMDA-receptors control these modulatory effects. However, hallucinations, which are among the principle symptoms of schizophrenia, imply a flaw in the interactions between neurons that is more fundamental than just a general weakness of contextual modulation.

The concept of locally specialized functions dominates research on higher brain function and its disorders. Locally specialized functions must be complemented by processes that coordinate those functions, however, and impairment of coordinating processes may be central to some psychotic conditions. Evidence for processes that coordinate activity is provided by neurobiological and psychological studies of contextual disambiguation and dynamic grouping. Mechanisms by which this important class of cognitive functions could be achieved include those long-range connections within and between cortical regions that (...) activate synaptic channels via NMDA-receptors, and which control gain through their voltage-dependent mode of operation. An impairment of these mechanisms is central to PCP-psychosis, and the cognitive capabilities that they could provide are impaired in some forms of schizophrenia. We conclude that impaired cognitive coordination due to reduced ion flow through NMDA-channels is involved in schizophrenia, and we suggest that it may also be involved in other disorders. This perspective suggests several ways in which further research could enhance our understanding of cognitive coordination, its neural basis, and its relevance to psychopathology. Key Words: attention; cerebral cortex; cognitive coordination; cognitive neuropsychiatry; cognitive neuropsychology; context disorganization; Gamma rhythms; Gestalt theory; glutamate; grouping; memory; NMDA-receptors; PCP-psychosis; perceptual organization; schizophrenia. (shrink)

This commentary highlights methods for using scalp EEG to make inferences about contextual field interactions, which, in view of the target article, may be specially relevant to the study of schizophrenia. Although scalp EEG has limited spatial resolution, prior knowledge combined with experimental manipulations may be used to strengthen inferences about underlying brain processes. Both spatial and temporal context are discussed within the framework of nonlinear interactions. Finally, results from a visual contour integration EEG pilot study are summarized in view (...) of a hypothesis that relates receptive field and contextual field processing to evoked and induced activity, respectively. (shrink)

Although context-processing deficits may be core features of schizophrenia, context remains a poorly defined concept. To test Phillips & Silverstein's model, we need to operationalize context more precisely. We offer several useful ways of framing context and discuss enhancing or facilitating schizophrenic patients' performance under different contextual situations. Furthermore, creativity may be a byproduct of cognitive uncoordination.

Context, connection, and coordination (CCC) describe well where the problems that apply to thought-disordered patients with schizophrenia lie. But they may be part of the experience of those with other symptom constellations. Switching is an important mechanism to allow context to be applied appropriately to changing circumstances. In some cases, NMDA-voltage modulations may be central, but gain and shift are also functions that monoaminergic systems express in CCC.

This commentary challenges the authors to use their computational modeling techniques to support one of their central claims: that schizophrenic deficits in bottom-up (Gestalt-type tasks) and top-down (cognitive control tasks) context processing tasks arise from the same dysfunction. Further clarification about the limits of cognitive coordination would also strengthen the hypothesis.

Schizophrenics exhibit a deficit in theory of mind (ToM), but an intact theory of biology (ToB). One explanation is that ToM relies on an independent module that is selectively damaged. Phillips & Silverstein's analyses suggest an alternative: ToM requires the type of coordination that is impaired in schizophrenia, whereas ToB is spared because this type of coordination is not involved.

Neurophysiological investigations of the past two decades have consistently demonstrated a deficit in sensory gating associated with schizophrenia. Phillips & Silverstein interpret this impairment as being consistent with cognitive coordination dysfunction. However, the physiological mechanisms that underlie sensory gating have not been shown to involve gamma-band oscillations or NMDA-receptors, both of which are critical neural elements in the cognitive coordination model.

N-methyl-d-aspartate receptor (NMDAR) dysfunction plays a crucial role in schizophrenia, leading to impairments in cognitive coordination. NMDAR agonists (e.g., glycine) ameliorate negative and cognitive symptoms, consistent with NMDAR models. However, not all types of cognitive coordination use NMDAR. Further, not all aspects of cognitive coordination are impaired in schizophrenia, suggesting the need for specificity in applying the cognitive coordination construct.

We propose that the primary cause of schizophrenia is a pathological extension of synaptic pruning involving local connectivity that unfolds ordinarily during adolescence. Computer simulations suggest that this pathology provides reasonable accounts of a range of symptoms in schizophrenia, and is consistent with recent postmortem and genetic studies. NMDA-receptors play a regulatory role in maintaining and/or eliminating cortical synapses, and therefore may play a pathophysiological role.

This commentary addresses: (a) the problems of definition which have been prominent in the use of the term context in schizophrenia research; (b) potentially useful distinctions and links with other theories of schizophrenic cognition; and (c) possible pathways to schizophrenic symptoms. It is suggested that at least two major aspects of the operation of context may be distinguished and that both may be impaired in schizophrenia.

Mechanisms that contribute to perceptual processing dysfunction in schizophrenia were examined by Phillips & Silverstein, and formulated as involving disruptions in both local and higher-level coordination of signals. We agree that dysfunction in the coordination of cognitive functions (disconnection) is also indicated for many of the linguistic processing deficits documented for schizophrenia. We suggest, however, that it may be necessary to add a timing mechanism to the theoretical account.

Evidence for a dysfunction in cognitive coordination in schizophrenia is emerging, but it is not specific enough to prove (or disprove) this long-standing hypothesis. Many aspects of the external world are spatially mapped in the brain. A comprehensive internal representation relies on integration of information across space. Focus on spatial integration in the perceptual and cognitive processes will generate empirical data that shed light on the pathophysiology of schizophrenia.

It is proposed that cortical activity is normally coordinated across synaptically connected areas and that this coordination supports cognitive coherence relations. This view is consistent with the NMDA- hypoactivity hypothesis of the target article in regarding disorganization symptoms in schizophrenia as arising from disruption of normal interareal coordination. This disruption may produce abnormal contextual effects in the cortex that lead to anomalous cognitive coherence relations.

Phillips & Silverstein argue that a range of cognitive disturbances in schizophrenia result from a deficit in cognitive coordination attributable to NMDA receptor dysfunction. We suggest that the viability of this hypothesis would be further supported by explicit implementation in a computational framework that can produce quantitative estimates of the behavior of both healthy individuals and individuals with schizophrenia.

The target article presents a model for schizophrenia extending four levels of abstraction: molecules, cells, cognition, and syndrome. An important notion in the model is that of coordination, applicable to both the level of cells and of cognition. The molecular level provides an “implementation” of the coordination at the cellular level, which in turn underlies the coordination at the cognitive level, giving rise to the clinical symptoms.

This commentary compares clinical aspects of ketamine with the amphetamine model of schizophrenia. Hallucinations and loss of insight, associated with amphetamine, seem more schizophrenia-like. Flat affect encountered with ketamine is closer to the clinical presentation in schizophrenia. We argue that flat affect is not a sign of schizophrenia, but rather, a risk factor for chronic schizophrenia.

This paper presents a version of neurophenomenology based on generative modelling techniques developed in computational neuroscience and biology. Our approach can be described as _computational phenomenology_ because it applies methods originally developed in computational modelling to provide a formal model of the descriptions of lived experience in the phenomenological tradition of philosophy (e.g., the work of Edmund Husserl, Maurice Merleau-Ponty, etc.). The first section presents a brief review of the overall project to naturalize phenomenology. The second section presents and evaluates (...) philosophical objections to that project and situates our version of computational phenomenology with respect to these projects. The third section reviews the generative modelling framework. The final section presents our approach in detail. We conclude by discussing how our approach differs from previous attempts to use generative modelling to help understand consciousness. In summary, we describe a version of computational phenomenology which uses generative modelling to construct a computational model of the inferential or interpretive processes that best explain this or that kind of lived experience. (shrink)