Imagine you have a diagnosis of schizoaffective disorder and you know you are getting unwell. You alert the mental health crisis team and they visit you each week. Each week they tell you to raise the dose of your anti-psychotic medication. But, despite this, you fall deeper into madness. You stay at home in your room. Over the weeks you hear a voice in your head. The voice sounds like thinking, but you know it is not your thinking. You can hear your own thinking on the left side of your brain. This other thinking is happening on the right side of your brain. It is the voice of God. You talk to this voice and ask it questions. During these weeks you uncover all the secrets you’ve kept hidden from yourself. And you discover the secrets of humanity. You learn that God walks the earth in human form, and that this form changes each generation. The God of this generation is telepathically communicating with you. And he keeps telling you to ‘think bigger’. By the time you are taken to hospital you know that you are the female aspect of God.
This happened to me in 1997. It was my third psychotic breakdown. It was a distressing but profound experience. And, it was an experience of thought insertion. This thesis attempts to explain thought insertion within the framework of philosophy of mind.
My honours thesis determines whether Van Gulick’s (2006, 2015) higher-order global state (HOGS) theory can account for thought insertion. Thought insertion is a positive symptom in schizophrenia where subjects claim they have thoughts that are not their own (Benson & Young, 2013). HOGS is a theory of consciousness. Thought insertion challenges theories of consciousness that claim there is a necessary connection between consciousness and subjectivity (Billon & Kriegel, 2015). HOGS is a well-developed theory that connects consciousness and subjectivity and is therefore a good model to test this challenge. This thesis has two aims. Primarily, I ask whether thought insertion is compatible with theories on which consciousness and subjectivity are closely connected, of which HOGS is a prime example. I critique Billon and Kriegel’s compatibilist solution to thought insertion and offer an alternative. This alternative leads to my second aim in the thesis, that is, developing an explanation for thought insertion. I claim that HOGS can account for thought insertion if two adjustments are made. Firstly, while normal functioning suggests we have one global state (GS), I suggest that two GSs are operating in subjects experiencing thought insertion. Secondly, I claim that the version of the self that Van Gulick posits, virtual-self realism (VSR), needs to be replaced with an autobiographical self (Damasio, 1999, 2012).
This paper discusses my thesis. Section 2 explains why this thesis is relevant by placing it in the context of philosophy and psychiatry and philosophy of mind. This thesis fills a gap in the literature by testing whether HOGS is compatible with, and can explain, thought insertion. Section 3 explains thought insertion and discusses background research in this area. Section 4 applies thought insertion to another subjectivity theory of consciousness, Rosenthal’s (2009b) higher-order thought (HOT) approach, to test whether it is compatible with thought insertion. I claim that HOT is compatible but lacks explanatory power. Section 5 explains HOGS and my two modifications to this model. I argue that HOGS is compatible with thought insertion and, further, that these two modifications enable HOGS to explain the phenomenology of thought insertion. Section 6 outlines the chapters of the thesis. Section 7 is a conclusion.
2. Relevance of thesis
2.1 Work in philosophy and psychiatry
This thesis is at the intersection of philosophy and psychiatry. This research area is growing, as illustrated by the size and breadth of The Oxford Handbook of Philosophy and Psychiatry (Graham et al., 2013). Research in this area has benefits for both disciplines (Parnas & Zahavi, 2000). Psychiatry can help us understand problems in philosophy of mind because symptoms in mental illness illustrate diverse mental functioning. This can help us understand what normal mental functioning is. Additionally, because these illnesses illustrate how consciousness ‘goes wrong’ they can help us test theories of consciousness (Gennaro, 2015). These theories have been developed to reflect normal functioning, but they must also account for diverse functioning. Symptoms can act as counter-examples to theories and when this happens they can help discredit a theory or show how a theory needs to be adjusted to account for a symptom. My thesis fits into this area of research. By testing whether HOGS can account for thought insertion, I use a symptom to test the merits of a theory. I claim the theory needs to be adjusted to account for the symptom.
Philosophy and psychiatry have further benefits for each other. Psychiatry can help philosophy because psychiatric illnesses reflect empirical facts about how the mind functions. Therefore, they are empirically informed ways to test intuitions about consciousness that can complement thought experiments (which are widely used in philosophy of mind). In turn, philosophy can help clarify the framework of psychiatry because it deals with issues that are relevant to mental illness, such as the self, self-identity and subjectivity. Thus, the conceptual clarity of philosophy can give insight into mental illness (Parnas & Zahavi, 2000).
Importantly, there are pragmatic implications of work between philosophy and psychiatry. My thesis is partly concerned with clarifying the phenomenology of thought insertion. Understanding the phenomenology of symptoms has implications for both understanding these illnesses and for treatment. Sass and Parnas (2013) argue that understanding how these symptoms are experienced can help explain these illnesses and can act as a constraint on neurobiological explanations because these explanations need to be in line with experience. In addition, Parnas and Gallagher (2015) claim that understanding how these symptoms are experienced can affect treatment. Most psychiatrists use the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) (Benson & Young, 2013) to diagnose patients. This can have a dehumanising effect on treatment because symptoms are often considered meaningless. For example, in thought insertion the content of thoughts is dismissed as irrelevant to treatment. Understanding is also limited because it is restricted to a third-person perspective. As a result, practitioners are not encouraged to relate in a humane and personal way with patients. Psychiatry could become more humane if the experience of patients were listened to. I try to explain how the experience of thought insertion is possible.
This thesis is relevant in another way that warrants mention. If we are to better understand mental illness, then people with lived experience of these illnesses need to be part of the conversation about these illnesses. And recognition that this is important is growing. There is also recognition that research, policy and practice need to influence each other in the field of mental health (Graham et al., 2013). People with experience of these symptoms and the mental health system need to be heard at all these levels if we are to improve treatment and understanding. My work is an offering in this direction.
2.2 Work in philosophy of mind
This thesis engages with issues that are relevant in philosophy of mind. Thought insertion is a symptom that can test theories of consciousness, such as HOGS. To grasp the importance of this, it is necessary to understand why consciousness is such a pressing issue in philosophy. Philosophers and scientists have been unable to account for phenomenal consciousness, that is, the qualitative aspect of our subjective experience. This has come to be known as the ‘hard problem’ of consciousness (Chalmers, 1996). Currently, there are numerous theories that attempt to explain this, such as HOGS.
The term ‘consciousness’ has various meanings and relates to a variety of related phenomena. We are conscious when we are awake but not when we are asleep, in a coma, or under anaesthetic. This usage is known as ‘creature consciousness’ and contrasts with mental states that are conscious. The next distinction is between ‘transitive’ and ‘intransitive’ consciousness (Rosenthal, 2009a). Transitive consciousness occurs when I am conscious of something; such as my colourful rug, or my thought that I want a coffee. In contrast, intransitive consciousness occurs even when a subject is not directly aware of something, as may be true in the case of moods; it is often assumed that intransitive consciousness is implicit and ubiquitous to our experience (Kriegel, 2009). Access consciousness and phenomenal consciousness form another distinction (Block, 1995). Access consciousness refers to a mental state that is ready to be used in processes involving reasoning and deliberation. Phenomenal consciousness refers to the qualitative dimension of our experience; the fact that my rug appears a certain colour to me, and that coffee smells a certain way to me. In this sense, there is ‘something it is like’ (Nagel, 1974) for me to have these experiences.
The ‘hard problem’ (Chalmers, 1996) of consciousness is the problem of phenomenal consciousness. That is, how can our physical brains give rise to our subjective experience? How is it that we experience this huge range of qualities – such as those we gain via sensory perception – colours, sounds, smells etc? This problem has two aspects. Firstly, how can this qualitative aspect of our experience be understood? Secondly, how can we understand the subjectivity of conscious states? Or, what does it mean to be a subject of experience? A range of theories have emerged to account for phenomenal consciousness. Some of these do not focus on the subjective aspect of this problem, whilst others see an important connection between the problem of consciousness and the problem of subjectivity (Kriegel, 2009; Levine, 2001).
Billon and Kriegel (2015) claim that thought insertion challenges theories that see a necessary connection between consciousness and subjectivity. In this sense, these theories are incompatible with thought insertion. HOGS is one such theory. Because theories of consciousness need to be able to account for symptoms there is value in determining whether HOGS can account for thought insertion. The strength of HOGS can be tested in this way.
Before describing HOGS, I now discuss thought insertion.
3. What is thought insertion?
Thought insertion is a positive symptom found in schizophrenia and other psychotic disorders. The DSM-5 classifies thought insertion as a delusion and describes it as the belief “that alien thoughts have been put into one’s mind” (Benson & Young, 2013, p. 87). One study found that 52% of people diagnosed with schizophrenia experience this symptom (Stephens & Graham, 2000) . The following are two quotes describing this experience:
I look out the window and I think that the garden looks nice and the grass looks cool, but the thoughts of Eamonn Andrews come into my mind. There are no other thoughts there, only his…He treats my mind like a screen and flashes thoughts onto it like you flash a picture (Mellor, 1970, p. 17).
Often, in a quiet place, and all the time at night when I am alone, I experience thoughts that do not feel like my own. It’s like they come out of a part of my brain that is not the part that controls my normal thoughts and into my awareness from there. It is hard to describe. These false thoughts are usually about random subject matter and usually make little sense, but are extremely distracting. Back when I first experienced them, I thought I was psychic and that I was picking up other people’s thoughts (telepathy?). However, now I know that they are a part of psychosis because I experience them around the times I hallucinate (Gunn, 2016, p. 562).
Thought insertion challenges philosophical ideas about self-consciousness. Self-consciousness, or self-awareness, is the awareness we have when we recognise ourselves as a subject, or self, that is having experiences. We assume that thoughts must belong to a person if they are self-conscious and the subject has introspective first-person access to them. However, in thought insertion, subjects claim they have introspective access to thoughts that do not seem to be their own (Smith, 2017).
Neurocognitive theories of thought insertion, such as the Comparator model (Frith, 1992, 2012), attempt to account for thought insertion by claiming it involves a problem with agency. Historically, Helmholtz (1866) tried to explain how we know we are the agents for our movements and suggested there is a motor command before we move, and we match this with the outcome of a movement. We know we are the agent when these match. Frith develops these ideas with the Comparator model. This is based on the idea that many positive symptoms in schizophrenia seem to involve a problem of agency. The Comparator model has become more sophisticated since it was first developed and now emphasises prediction rather than monitoring. It was initially applied to thought insertion. However, despite empirical support suggesting it explains some symptoms, it is unable to account for thought insertion (Frith, 2012). Gallagher (2004) emphasises this limitation, arguing that a model for movement cannot be applied to thoughts.
Stephens and Graham (2000) defend what is known as the Standard model of thought insertion. They distinguish between agency and authorship or ownership of thoughts. Subjects claim they are not the agent or author of inserted thoughts. However, they recognise that they ‘own’ the thoughts in the sense that they occur within the boundaries of their psychological history. Stephens and Graham (1994) suggest that we feel ourselves to be agents of our thoughts when we know our underlying intentional states. We identify thoughts as being our own because they align with our overall understanding of ourselves, our intentions and desires. Inserted thoughts do not align with how subjects understand themselves and so they are rejected. While this is a top down approach, Gallagher (2000b) offers a bottom up approach. He suggests that non-psychotic thoughts are preceded by a feeling of anticipation, and this is absent in thought insertion. The problem with these approaches is that they do not distinguish inserted thoughts from obsessive or unbidden thoughts where we also feel we are not the agents. For example, people with obsessive compulsive disorder (OCD) often experience intrusive thoughts and yet, while they may not feel like the agents of these thoughts, they are not disowned (Billon, 2013).
I explore thought insertion via the approach outlined by Billon and Kriegel (2015). While research into thought insertion has been concerned with modelling this phenomenon and has focused on explaining the role of agency, I address Billon and Kriegel’s claim that thought insertion is incompatible with theories of consciousness that connect consciousness and subjectivity. One way to interpret thought insertion is that subjects are conscious of thoughts that do not seem to be subjective. This implies consciousness without subjectivity. This challenges what Billon and Kriegel call ‘subjectivity theories’, such as HOT and HOGS. Billon and Kriegel offer their own compatibilist solution to thought insertion that I critique in my thesis. I claim their solution fails. I then illustrate how HOGS, once adjusted, can overcome the challenge thought insertion poses. In addition, I show how HOGS has explanatory power. Subjects claim they experience thoughts that are not their own. By showing how HOGS can account for this, I show that HOGS can be used to model this symptom.
I now apply thought insertion to HOT. This theory also connects consciousness and subjectivity and can therefore be used to assess Billion and Kriegel’s claim that thought insertion is incompatible with subjectivity theories.
4. Applying thought insertion to HOT
Rosenthal (2009b) supports a higher-order thought (HOT) approach to consciousness. Higher-order representational theories of consciousness suggest that the subjective dimension of our conscious experience is due to an (often unconscious) higher-order mental state being directed at the first order conscious state. For Rosenthal, a state becomes conscious because there is a higher-order thought or belief about the first order state and as a result the subject is aware of herself experiencing that state. So, when I smell my coffee there is a higher order state that contains the belief I am smelling this coffee. This higher-order state results in my awareness of both the smell of the coffee and the fact that I am having this experience. In this way, subjectivity is necessarily bound to my conscious experience.
To claim that HOT is incompatible with thought insertion because HOT links consciousness with subjectivity would be to understand this problem in the following (mistaken) way: Because the inserted thoughts are experienced as not belonging to the subject, they are not represented by a higher-order state (recall, it is this higher-order state that gives the thoughts their subjectivity). As such, the inserted thoughts are only represented by a first order state. This would contradict HOT, which claims that a higher-order state is necessary for the thoughts to be conscious. Two conclusions can be drawn from this, either; 1) HOT is false or; 2) subjects do not experience conscious inserted thoughts (because they are not represented by a higher-order state). However, empirical reports show that subjects do experience conscious inserted thoughts. Thus, Rosenthal must be wrong. However, I suggest that this interpretation of the problem is mistaken.
Subjects complain about experiencing the inserted thoughts, so these thoughts must be conscious thoughts. As such, they can be understood as being represented by a higher-order state. This is in line with Rosenthal’s claims.
For example, if a subject has an inserted thought that the apple is green
They would have:
Higher-order state: The belief “I am having a thought the apple is green.”
First-order state: The thought the apple is green
It is possible to interpret Rosenthal’s theory as being able to account for the inserted thoughts. They are conscious thoughts because they are represented by a higher-order state. But there is still a difficulty with Rosenthal’s approach. This is because, in addition to the subject’s belief that they are having these thoughts, they have another belief that these thoughts do not belong to them. For example, in addition to the belief:
“I am having a thought that the apple is green.”
There is the added belief that:
“This thought is not my own”
The challenge for Rosenthal is to account for this additional belief.
I suggest that HOT is compatible with thought insertion. However, HOT does not have the explanatory power to account for thought insertion. In contrast, I argue that HOGS, once modified, does have this explanatory power.
I now discuss HOGS in detail.
5. What is HOGS?
Robert Van Gulick’s (2006, 2015) higher-order global state (HOGS) theory is a view of the mind and consciousness according to which minds are biological aspects of the world. Organisms are goal directed, and minds have evolved to help them better adapt to their environments via an understanding of themselves. Higher-order approaches to consciousness claim that a mental state is conscious if an organism is aware of being in that state, and Van Gulick argues that self-awareness is an important part of consciousness. The central claim of HOGS is that we experience phenomenal consciousness because we “embody…a rich store of implicit and procedural self-understanding at the subpersonal level” (2006, p. 23).
Van Gulick claims a non-conscious mental state becomes conscious when it is recruited into a global state (GS). This GS underlies our moment by moment conscious experience. For example, if I have an unconscious visual perception this can be integrated into the GS. When this happens the area of the visual cortex remains active but, when the visual perception becomes conscious, the activity in the visual cortex is integrated into the overall structure and activity of the GS. When information becomes conscious in this way it is more influential throughout the brain because this information is accessible to more of the brain’s subsystems.
HOGS connects consciousness with subjectivity because information in the GS becomes integrated and forms a unified point of view that acts as a self or subject. Information in the GS is transformed and becomes highly reflexive. This reflexivity accounts for why the subject is aware of a conscious state. The higher order (HO) aspect of HOGS is embedded in the GS. This HO aspect transforms the intentionality of the conscious state (for example, a visual perception) and makes the perception part of a subject and part of a unified world that the subject is experiencing (2015). Van Gulick claims that non-conscious information becomes conscious because it is recruited “into a globally integrated complex whose organization and intentional content embodies a heightened degree of reflexive self-awareness” (2006, p. 24).
This leads to questions about what a self is and what challenge thought insertion poses to HOGS. Van Gulick (2015) posits a version of the self that he terms virtual self realism (VSR). In VSR, the self is not an entity over and above experience. Instead, it emerges when experiences in the GS combine to form a point of view. This point of view is the unified subject. VSR develops Dennett’s (1992) ideas about the virtual self. However, unlike Dennett, Van Gulick see the self in VSR as being a real causal entity or structure, not simply an intentional entity. Because a self emerges when the contents of the GS bind together and form a point of view, Van Gulick clearly links consciousness and subjectivity. Consequently, HOGS is challenged by thought insertion. To claim HOGS is incompatible with thought insertion would be to suggest that the inserted thoughts, whilst being conscious, do not form a point of view (or subject) in the GS. However, I suggest that this interpretation is incorrect. Instead, I claim that HOGS can account for the inserted thoughts if two GSs are posited. I attempt to show how the subject is in one GS, while the inserted thoughts occur in a different GS.
My first adjustment to HOGS is to suggest that more than one GS is possible in one individual. Van Gulick (2015) discusses HOGS in relation to dissociative identity disorder (DID) where subjects seem to have more than one personality. He suggests that an individual cannot have more than one self in a GS. But he suggests that the possibility of more than one GS requires investigation. I argue that there are two GSs in thought insertion. However, unlike DID, I do not claim that there is more than one ‘personality’ in thought insertion. If a subject experiencing thought insertion has two GSs – that is, GS1 and GS2 – then the inserted thoughts can become conscious in GS2 where they form a point of view. However, the ‘subject’ that the individual identifies as being ‘themselves’ is contained in GS1. This explains why the inserted thoughts are experienced as distinct from the subject.
My second adjustment to HOGS is to see if VSR can be replaced by an autobiographical self in GS1. An autobiographical self is similar to a narrative self which refers to personal identity and continuity across time (Gallagher, 2000a). I draw on Damasio’s (1999, 2012) autobiographical self because it is an empirically well-developed thesis. Work by Damasio with brain-damaged patients shows that subjects who have damage to episodic memory have trouble functioning as their awareness is limited to a small window of time. It seems we need a sense of ourselves continuing over time to function as agents. If, in thought insertion, the ‘subject’ is identified with the autobiographical self in GS1 this may explain why subjects reject ownership of the inserted thoughts, occurring in GS2. I suggest that the self in GS2 is an impoverished self where sub personal information has made its way into consciousness by being part of this separate GS. I further suggest this information is not accessible, via episodic memory, to the autobiographical self in GS1.
I have yet to establish these claims. However, my thesis attempts to construct a workable model from these ideas that is true to empirical reports of subjects and explains how the phenomenology of thought insertion is possible.
I now outline the chapters of this thesis.
6. Chapters of thesis
I introduce the topic and define thought insertion and HOGS. I explain the problem that thought insertion poses to subjectivity theories of consciousness. I introduce the two claims I defend in this thesis. Firstly, that HOGS is compatible with thought insertion. Secondly, that HOGS has the explanatory power to account for the experience of thought insertion if two adjustments to this model are made. These are; 1) there are two GSs in the one subject (as opposed to one in normal subjects) and; 2) the notion of a self (VSR) that Van Gulick employs is replaced with an autobiographical self.
This chapter sets out the problem that thought insertion poses to subjectivity theories of consciousness. I outline some background literature on thought insertion. I then discuss subjectivity theories and Billon and Kriegel’s claim that thought insertion is incompatible with these. I apply thought insertion to HOT and discuss the strengths and limitations of HOT. I conclude that while HOT is compatible with thought insertion, it lacks explanatory power.
This chapter critiques other compatibilist approaches to the problem that thought insertion poses to subjectivity theories. Particularly, I analyse the strategy used by Billon and Kriegel to solve this problem. Billon and Kriegel offer two arguments to account for thought insertion. Firstly, they attempt to distinguish between two different types of subjectivity and argue that in thought insertion subjects are experiencing something ‘extra’ in their phenomenology. Their second approach is to distinguish between two different uses of the term ‘consciousness’. They claim that inserted thoughts are reflectively conscious but are not phenomenally conscious. I claim that their approach fails, and I show why. It is the limitations of their approach that creates the gap in the literature that I fill in the following chapter where I offer an alternative compatibilist approach.
Having argued that HOT is compatible with thought insertion and that Billon and Kriegel’s compatibilist solution fails, I further argue that both HOT and Billon and Kriegel’s approach cannot explain the phenomenology of thought insertion. In this chapter, I offer my own compatibilist solution. However, showing that a theory is compatible with thought insertion does not entail that it can explain this symptom. Thus, my aim in this chapter is to show how HOGS, once adjusted, has the explanatory power to account for thought insertion. I explore the two modifications that I believe are necessary. That is, how does HOGS work when more than one GS is posited? And can Damasio’s autobiographical self be integrated into Van Gulick’s model? I explain why HOGS needs an autobiographical self in GS1. This is because the ‘subject’ is found in GS1 while the inserted thoughts are experienced in GS2. Moreover, the ‘subject’ is identified with an autobiographical self, while the inserted thoughts in GS2 result in a more impoverished self. I discuss the strengths and limitations of my approach.
I do a textual analysis of empirical reports of the experience of thought insertion to test the model I develop in the previous chapter and determine whether it can explain the phenomenology of thought insertion. These reports will be drawn from the literature and open online mental health consumer forums. I address any limitations found.
I conclude with a summary of my argument, that is, that HOGS is compatible with thought insertion. Further, HOGS can explain the experience of thought insertion if two adjustments are made. Firstly, a subject must be able to have more than one GS. Secondly, VSR needs to be replaced with an autobiographical self to account for the subject in GS1. I discuss implications of the findings. Implications include insight into how the mind functions and an analysis of the strength of HOGS as a theory of consciousness. In addition, making sense of the phenomenological reports of patients may increase the understanding of practitioners and improve treatment. Suggestions for future research include further testing theories of consciousness and determining their ability to account for psychopathological symptoms. Specifically, how these symptoms are experienced.
This paper has explored my honours thesis. I have placed my thesis in the context of work in philosophy and psychiatry and philosophy of mind. I then discussed thought insertion and tested its compatibility with HOT. Following this, I discussed HOGS. The goal of my thesis is to assess the compatibility of HOGS with thought insertion and, additionally, to show how HOGS can explain the phenomenology of thought insertion if adjusted. Understanding symptoms, specifically how they are experienced, can impact treatment and lead to better outcomes for patients. These symptoms also give us insight into consciousness. As such, this is a fertile research area.
Many thanks to my supervisor, Daniel Stoljar at ANU, for his input into this work.
Benson, R. S., & Young, M. L. (Eds.). (2013). American Psychiatric Association: Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition. Arlington, VA: American Psychiatric Association.
Billon, A. (2013). Does consciousness entail subjectivity? The puzzle of thought insertion. Philosophical Psychology, 26(2), 291-314. doi:10.1080/09515089.2011.625117
Billon, A., & Kriegel, U. (2015). Jaspers’ Dilemma: The Psychopathological Challenge to Subjectivity Theories of Consciousness. In R. Gennaro (Ed.), Disturbed Consciousness (pp. 29-54): MIT Press.
Block, N. (1995). On a confusion about a function of consciousness. Brain and Behavioral Sciences, 18(2), 227-–247.
Chalmers, D. J. (1996). The Conscious Mind: In Search of a Fundamental Theory. Cary: Oxford University Press.
Damasio, A. R. (1999). The feeling of what happens: body and emotion in the making of consciousness (1st ed.). New York: Harcourt Brace.
Damasio, A. R. (2012). Self comes to mind: constructing the conscious brain (1st Vintage ed.). New York: Vintage Books.
Dennett, D. C. (1992). The self as a center of narrative gravity. In F. S. Kessel, P. M. Cole, & D. L. Johnson (Eds.), [Book Chapter] (pp. 4–237): Lawrence Erlbaum.
Frith, C. (1992). The cognitive neuropsychology of schizophrenia. Hove, U.K;Hillsdale, U.S;: L. Erlbaum Associates.
Frith, C. (2012). Explaining delusions of control: the comparator model 20 years on. Consciousness and Cognition, 21(1), 52.
Gallagher, S. (2000a). Philosophical conceptions of the self: implications for cognitive science (Vol. 4, pp. 14-21): Elsevier Ltd.
Gallagher, S. (2000b). Self-reference and schizophrenia: A cognitive model of immunity to error through misidentification. In D. Zahavi (Ed.), Exploring the Self : Philosophical and psychopathological perspectives on self-experience. Philadelphia, NETHERLANDS: John Benjamins Publishing Company.
Gallagher, S. (2004). Neurocognitive Models of Schizophrenia: A Neurophenomenological Critique. Psychopathology, 37(1), 8-19. doi:10.1159/000077014
Gennaro, R. J. (2015). Psychopathologies and Theories of Consciousness: An Overview. In R. J. Gennaro (Ed.), Disturbed Consciousness: New Essays on Psychopathology and Theories of Consciousness. Massachusetts, USA.: MIT Press.
Graham, G., Sadler, J., Strangellini, G., & Thornton, T. (2013). The Oxford Handbook of Philosophy of Psychiatry. Oxford, UK: OUP.
Gunn, R. (2016). On Thought Insertion. Review of Philosophy and Psychology, 7(3), 559-575. doi:10.1007/s13164-015-0271-2
Helmholtz, H. V. (1866). Handbuch der Physiologischen Optik. Voss, Leipzig.
Kriegel, U. (2009). Subjective Consciousness: A Self-Representational Theory: Oxford University Press.
Levine, J. (2001). Purple haze: the puzzle of consciousness. New York: Oxford University Press.
Mellor, C. S. (1970). First Rank Symptoms of Schizophrenia. The British Journal of Psychiatry, 117(536), 15-23. doi:10.1192/bjp.117.536.15
Nagel, T. (1974). What Is It Like to Be a Bat? The Philosophical Review, 83(4), 435-450. doi:10.2307/2183914
Parnas, J., & Gallagher, S. (2015). Phenomenology and the interpretation of psychopathological experience. In L. Kirmayer, R. Lemelson, & C. Cummings (Eds.), Revisioning Psychiatry Integrating Biological, Clinical and Cultural Perspectives. Cambridge: Cambridge University Press.
Parnas, J., & Zahavi, D. (2000). The link: Philosophy – Psychopathology – Phenomenology. In D. Zahavi (Ed.), Exploring the Self : Philosophical and psychopathological perspectives on self-experience. Philadelphia, NETHERLANDS: John Benjamins Publishing Company.
Rosenthal, D. M. (2009a). Concepts and Definitions of Consciousness. In W. P. Banks (Ed.), Encyclopedia of Consciousness. Amsterdam: Elsevier.
Rosenthal, D. M. (2009b). Higher-Order Theories of Consciousness. In B. McLaughlin, A. Beckermann, & S. Walter (Eds.), Oxford Handbook of Philosophy of Mind. Oxford, UK: Oxford University Press.
Sartorius, N., Jablensky, A., & Shapiro, R. (1977). Two-year follow-up of the patients included in the WHO International Pilot Study of Schizophrenia. Psychological Medicine, 7(3), 529-541. doi:10.1017/S0033291700004517
Sass, L. A., & Parnas, J. (2013). Explaining schizophrenia: the relevance of phenomenology. In M. Cheung Chung, B. Fulford, & G. Graham (Eds.), Reconceiving Schizophrenia. Oxford, UK: Oxford University Press.
Smith, J. (2017). Self-Consciousness. In E. N. Zalta (Ed.), The Stanford Encyclopedia of Philosophy Stanford: Stanford University.
Stephens, G. L., & Graham, G. (1994). Self-Consciousness, Mental Agency, and the Clinical Psychopathology of Thought-Insertion. Philosophy, Psychiatry and Psychology, 1(1), 1.
Stephens, G. L., & Graham, G. (2000). When self-consciousness breaks: alien voices and inserted thoughts. Cambridge, MA;London;: MIT Press.
Van Gulick, R. (2006). Mirror Mirror – Is that all? In U. Kriegel & K. Williford (Eds.), Self-Representational Approaches to Consciousness. Massachusetts, USA: MIT Press.
Van Gulick, R. (2015). Altogether Now – Not! Integration Theories of Consciousness and Pathologies of Disunity. In R. J. Gennaro (Ed.), Disturbed Consciousness: New essays on psychopathology and theories of consciousness. Massachusetts, USA: MIT Press.