Franco Bertossa, Marco Besa, Roberto Ferrari, Francesca Ferri
Centro Studi ASIA – via Riva Reno n.124, 40121 Bologna, Italia
Pubblicato in Perceptual and Motor Skills, 2008, 107, 323-335.
correspondence to: email@example.com
Thank to the volunteers and Loretta Secchi for recruiting blind subjects. Laura Podda cooperated in the phase of collecting data; Paolo B. Casartelli, Ricardo Pulido and Kristerfor T. Mastronardi improved the text in English. Very special thanks to Nicholas Humphrey and John Skoyles for having reviewed the manuscript, providing suggestions and encouraging the publication. Thanks to the anonymous reviewers for their critical comments and suggestions. This work is dedicated to the memory of Francisco J. Varela, whose studies on the first person approach provided the starting point for these investigations.
Summary. Does consciousness have a spatial “location” that can be scientifically investigated? Using a novel phenomenological method, when people are encouraged to explore the question introspectively they not only can make sense of the idea of their consciousness being “located”, but will readily indicate its exact position inside the head. The method, based on Francisco J. Varela’s work and Neurophenomenology approach, involves a structured interview with untrained volunteers led by an expert mediator in which preliminary questions are asked about the location of objects and body parts, and then about the location from which they are experiencing these objects. 83% of volunteers located with confidence a precise position for the I-that-perceives in the temporal area of the head centred midway behind the eyes. The same results were obtained with blind subjects (congenitally or later) and with non-Westerners. The significance of this subjective source of the experience of the location of perception is discussed linking it to neurological correlates of self-referred conscious activities and of conscious awareness in memory. Further investigations are suggested with trained volunteers and with individuals with psychiatric disorders.
Philosophers and neuroscientists have regularly poured scorn on the idea that consciousness might have a precise physical location: “You enter the brain through the eye, march up the optic nerve, round and round in the cortex, looking behind every neuron, and then, before you know it, you emerge into daylight on the spike of a motor nerve impulse, scratching your head and wondering where the self is” (Dennett, 1989, p. 164).
It would be difficult to deny the existence of conscious experience from a subjective first person perspective, and it is inconsistent to postulate the non existence of the self, because without the self there is no first person. But examining the conscious experience Varela, Thompson and Rosch (1991) noted that if somebody asks us to look for the self, we would have so much to do to look for it, thus highlighting the difficulty in answering the question: “where am I?” For Varela (1999) consciousness is extended to the whole body, a ‘not-place’ distributed in the net of organism, its movements, its environment. Clark (2003) proposed an “extended mind” including physical, physiological, linguistic, and social environments: mind is extended as far as is extended its actions and interactions.
From a third person research perspective, brain imaging studies have been conducted to characterize and locate in brain areas associated with some self-referred mental activities (Goldberg, Harel, & Malach, 2006; Gusnard, Akbudak, Sulman, & Raichle, 2001; Kjar, Novack, & Lou, 2002). Tulving & Lepage (2000) investigated in the brain where the activity correlated with the autonoetic awareness of one’s past is observed.
Not denying this dimension of the self in the third person, we want to compare it with the examined experience in the first person.
Tempting a phenomenology of mind, Clarke (1995) claimed that mental objects are non-spatial; he admits only for visual percepts and thoughts, and for dreams, an internal space where objects are located, denying it is a structural aspect but only a “temporary presentation device” (p. 167) derivate from eyesight and contemplated physical space. McGinn (1995), starting from Descartes’ intuition that ‘pure thought’ is not spatial as matter, extend this feature to all experiences and imaginations: terms like form, dimension, and position would not make any sense if referred to the conscious subject and to conscious events, because these are not perceptual objects. For McGinn, if a conscious event appears to be located in a inner space in the vicinity of brain, i.e. “I locate my thoughts nearer to my head than to my feet”, this judgment no more than “a sort of courtesy location” (p. 98) derived from causal considerations of the brain’s role in controlling mental life. Other researchers emphasize the importance of leaving the question open: “Of course, in order to learn what something is, it is useful in the initial instance to know where it is, so that one can point to it – enabling the attention of different investigators to be focused upon it. But where does one point, when one is pointing at consciousness?” (Velmans, 1996, p. 183). With Velmans, we belive that the significance of such a question is to focus the attention of different investigators on a single phenomenological place, and to compare understanding and observations. Finding the subjective physical location of consciousness would mean finding the seat from which all experiences occour apart from their sensory field of origin (sight, hearing, touch, etc.).
Until now few researchers (Petitmengin-Peugeot, 1999) have listen to what people actually have to say about consciousness. Starting from the assumption that the first person subject should be considered an authority on consciousness, we adopted the method of asking people about their lived experience. Specifically three issues were investigated: (1) can people naïve to phenomenological training about consciousness understand the question?; (2) can such people actually locate a precise seat for “I-that-perceives”?; (3) is this ability independent of culture and sense of sight?
A structured interview procedure was used within a phenomenological “second-person” approach (Varela & Shear, 1999; Velmans, 1998, 2000b; Vermersh, 1999; Petitmengin, 2006), which involves an expert person acting as an intermediary between the first-person experience of the volunteers and the third-person report they make of that experience.
59 sighted and blind volunteers (23 students, 32 employed and 4 retired people; Md. age=33, range 18-66) were recruited and investigated. 51 sighted volunteers were recruited with written announcement in town university area; 46 were Westerners and five non Western (from Morocco, Eritrea, Pakistan, Sri Lanka and Philippines): this small number of people from other cultures was recruited to assess possible cultural attitude in the localization of consciousness. Eight blind Westerners volunteers (five with acquired blindness and three with congenital blindness) were recruited by contacting an Association for the blind and included in the sample to verify whether spatial localization of consciousness was based on the sense of sight or not. None of the subjects were friends or acquaintances of the interviewers, nor were they engaged in academic courses on introspection, phenomenology, or meditation.
A first-person approach demands a phenomenological description of experience with precise distinctions, but in investigating untrained people neither their accuracy in filling out questionnaires nor their frankness in verbal accounts are sufficient to ensure that the experimental data stem from an authentic and genuine examination of the conscious experience. To tackle this problem, the volunteers were interviewed separately using a semi-structured interview following a methodology for second-person investigation (Vermersh ,1999; Varela & Shear, 1999) with an expert person acting as an intermediary between the experience in first-person of the volunteer and the report in third-person of that experience.
The intermediary or mediator must be able to help each subject open himself and self-observe the inner phenomenology. Through opportune questions (see transcription of interviews in Results), he must guide the process of verbalization and make sure all the volunteers go through the same series of steps. Mediators need an adequate scientific qualification and mastery the method, gained in several years of both philosophical (phenomenological reduction) and pragmatic (mindfulness meditation) training (Bertossa & Ferrari, 2006). Only through a systematic exercise is it possible to pass from “an episodic incursion into consciousness” (Varela, 1996) to the ability to stabilize our attention in a prolonged way on conscious experience. The training of the mediator must be completed with the acquisition of empathic, communicative and listening abilities that are necessary to guide the volunteers to produce a verbal report of their experience in first-person.
Steps and thematic areas of interview
The interview was constructed using the three stages employed by Petitmengin-Peugeot (1999), and the three steps proposed by Depraz, Varela, and Vermersh (2003). The first phase (thematic areas 1-3, see below) aimed to produce a “suspension” of speculative thoughts and prejudice, thus clearing the way for the volunteer to pay attention to his lived experience. The second phase (thematic area 4) aimed to “redirect” attention from the exterior to the interior, guided by proprioceptive sensations, while specifically avoiding engaging with their quality or content, so that attention could be paid to their location and the “flow” of perception. The third phase (thematic areas 5) asked volunteers to “let go” and be receptive to the emerging experience, and so to make themselves open to the experience.
Each volunteer was introduced to the interview after sitting down, comfortably and quietly. He was requested to answer and follow the forthcoming questions simply using direct perception, without any speculative attitude. The interview protocol was not a questionnaire with a rigid series of prearranged questions, but a semistructured sequence of thematic areas to be discussed and examined thoroughly, favouring contents and their completeness. Every thematic area represents a stage of a logical and hierarchic succession where each issue has to be exhausted before going on to the following stage (as the example in fig.1). The specific contents of each of the thematic areas were:
1. Visual (tactile) perception of space. Volunteers were invited to recognize the distance and location of simple objects with respect to the body.
2. Distinction of subject-object. Volunteers were directed with questions to recognize the usual and naïve experience of the difference between subject that perceives and object that is perceived.
3. Visual (tactile) perception of the subject-object direction. Volunteers were invited to recognize the way objects are directed in respect to the I-subject that moves perceived objects nearer or farther away. In this and all preceding areas, the interviewer makes clear the difference between the description of an actual experience, and its description in remembered experiences, beliefs, comments, judgements, and emotions. Through questions he creates the conditions in which the volunteer is constantly referred back to his direct experience.
4. Proprioception (with closed eyes). Volunteers were invited to consider the distance and the location in space of various parts of the body with respect to the I-that-perceives them. The distance and directionality of this are specified through body movements and changes in the proprioceptive feel of how they are attended. The purpose of this part of the interview is to prepare the subject for identifying the location of the I-that-perceives.
5. Location of the seat of consciousness. Thematic area 4 gradually shifted into thematic area 5 by referring to parts of the body that are perceived as being nearer to or farther from the I-that-perceives. After this progressive “moving back and forth of the flow of perception”, volunteers were invited to make an attempt to locate the first-person “source of perception”.
(i) Volunteers were invited to give an opinion whether they sense there is such a location;
(ii) Volunteers were invited to indicate by pointing, using the forefingers of each hand positioned orthogonally to the other, the place that is detected as the source of perception;
(iii) Sighted volunteers who pointed to a spatial location of the I-that-perceives in the head were then asked to represent the position on two human profiles, one frontal and the other lateral.
Each interview lasted at most an hour. A detailed video record was made and reviewed by other researchers for independent assessment and validation.
Fig 1: Scheme of the interview.
(Click to enlarge the image)
The results are summarized in Table 1. The main finding was that 90% of the participating volunteers found it natural to locate the I-that-perceives inside their body. Furthermore, 83% of these pointed out a location of the I-that-perceives in what they felt was a precise point inside the head. The eight blind subjects and five non Western volunteers gave answers that were very similar to those given by the 54 sighted Western volunteers.
Tab. 1: Location of "I-that- perceives"
|Location of the I
|Precise point inside the head
Generally inside the head
Generally inside the body
In the belly
Most volunteers, when moving their fingers up and down, reported a defined location. The sighted volunteers indicated a precise point and not an extended area of a human profile; when all the data from the points drawn were superimposed, they were quite widely dispersed in the lateral plane, and arranged along the mid-line in the frontal plane of the human profile. The terms that volunteers introduced during the interview to indicate this experience were “I”, “centre of me”, “here”, “my point of observation”. In this work we use the terms “I-that-perceives” and “point zero” to indicate this subjective location of experience.
Fig 2: Distribution of the points indicated by the volunteers, drawing a sign on a human shape, as a place of consciousness.
The significance of the results lies in the evidence that, since all conscious humans have a sense of I, here for the first time there is a large consent in answering to the question “Where is the I-that-perceives?”, indicating a precise seat that is reference point for conscious localization of internal and external objects in space.
To provide a qualitative description of method and results, we will comment on some exemples of thematic areas of the interview protocol, and then provide a description of the six cases in which the interviewed volunteers were not able to detect any seat of consciousness. Verbal descriptions given by the eight blind volunteers and the five non Westerners were comparable to those of the sighted and Western participants; the locations of “I-that-experiences” were completely similar and thus are described without making any distinctions.
Thematic Area 1: Introduction to perception of space
Fig 3: Thematic Areas 1-2 - Perception of space and distinction between the perceiver and the perceived object.
Starting from the analysis of common and completely clear events, the interviewer used simple exercises to create conditions that maintained the volunteer’s attention on his being-experiencing. It is necessary to separate the phenomenological perception of space, resolving the difference between the verbal report of a sensorimotor or cognitive experience while in action as compared to the description of other experiences to be suspended: memories about perception of space, beliefs, comments, judgements, and emotions. For example:
Interviewer: Can you tell me if one of these two objects is closer and the other one is farther?
Volunteer No. 46: The pen is closer and the plant is farther.
Through simple exercises of this type it is easily highlighted that when we perceive something we also perceive it at a certain distance which, with a certain approximation, we are able to evaluate and compare.
Interviewer: Can you tell me where the ceiling is with respect to you?
Volunteer No. 46: It is above me.
At this stage, the interviewed people have been asked to use touch or sight to examine their experiences in the moment when any event of perception occurs.
Interviewer: Consider any object in this room.
Volunteer No. 42: That chair by your side.
Interviewer: Who has considered this chair?
Through this type of question the interviewed people have noticed, without it being assumed beforehand or suggested by the interviewer, the existence of a bipolar structure in their usual conscious experience: what is somehow perceived, and what perceives in us.
Interviewer: Try to put a hand in front of you.
Volunteer No. 44: [brings the hand in front of the body]
Interviewer: With respect to what are you able to determine the position of your hand?
Volunteer No. 44: To myself.
In this way the interviewed person recognized that the reference point about which he is able to determine the distance and the location of the perceived objects is just the “I” (or “myself”).
Thematic Area 3: Perception of direction of subject-object movement
Interviewer: Take this object and move to a further position.
Volunteer No. 59: [puts the object in a faraway point from the body]
Interviewer: Now bring it nearer.
Volunteer No. 59: [brings it close to the chest]
Thematic Area 4: Proprioception with closed eyes
Often this stage would foster a state of greater tranquillity in the volunteers and help them to stabilize their attention on the tasks that were assigned. Through the use of the proprioception, the various parts of the body were recognized as distinct parts with respect to the I-that-perceives.
Volunteer No. 10: The hand can be perceived by the I, but at the same time it is also something that perceives.
Interviewer: Is your hand “I”, or does your “I” perceive through your hand?
Volunteer No. 10: It is a channel of perception, it is not the I.
Volunteers were able to associate the proprioception of each part of the body with a sensation of closeness or distance with respect to “I”. Volunteers were asked to single out parts of the body that were perceived as closer and further, in order to identify a course of gradual approach to the I-that-perceives. (The following interchange is with respect to the “I”).
Interviewer: Is there a zone between your belly and your throat that you feel closer?
Volunteer No. 46: The throat.
Interviewer: If you feel your mouth, where do you feel it?
Volunteer No. 46: Downwards.
Interviewer: If you feel your scalp, where do you feel it ?
The course of approach to the “I” has been used to identify a precise spatial trajectory between the subject and any object perceived. Once achieved a clear recognition of a trajectory in the perceptive flow of the conscious I, the following step is the attempt to locate the I.
Thematic Area 5: Attempt to locate the subjective physical location of consciousness
Fig 5: Thematic Area 5 - Attempt to locate the site of consciousness.
Most of the volunteers gave descriptions with a high level of detail until they indicated a precise seat inside the head at which the spatial trajectory ended and where the spatial perception had its origin.
Interviewer: When you draw your attention to your throat, from where do you perceive it?
Volunteer No. 46: From the head.
Interviewer: Try to indicate with a finger the direction from which you perceive the eyes.
Volunteer No. 46: From here [indicates with the finger a direction that goes from the centre of the head].
Interviewer: Try to keep your finger pointed like you have done now.
Volunteer No. 46: Towards my point of observation?
Interviewer: Yes, exactly. Now try to indicate this “point of observation” using both forefingers to create two imaginary lines that produce a system of orthogonal coordinates.
Volunteer No. 46: [indicates a point inside the head].
Interviewer: This point that you are indicating inside your head, where do you feel it in the space?
Volunteer No. 46: It is before.
Interviewer: Then try to move your coordinate system a little backwards.
Volunteer No. 46: Here behind the ear [draws only the forefinger of the hand on the side of the head a few centimetres back].
Interviewer: Now are you indicating a different point from the previous one?
Interviewer: Where is this point in the space?
Volunteer No. 46: Here, it is neither before nor behind.
Interviewer: Are you exactly indicating what you have called “my point of observation”?
For Volunteer No. 47, a similar procedure has been used but with some small variations:
Interviewer: Try to feel your eyes. From where do you feel them?
Volunteer No. 47: [the subject has the eyes closed] From inside the head.
Interviewer: Try to indicate from where you feel them.
Volunteer No. 47: [The subject indicates a point inside the head].
Interviewer: This point that you are indicating, do you feel it upwards, downwards, on the right, on the left, over or under?
Volunteer No. 47: I feel it downwards.
Interviewer: Then try to indicate a point a little bit above.
Volunteer No. 47: [follows the instruction].
Interviewer: Now are you indicating a different point as compared to the previous one?
Interviewer: Where do you feel this point?
Volunteer No. 47: I feel it closer but a little bit lower.
Interviewer: Then, like before, try to move with the forefingers and to verify where you feel this new point.
Volunteer No. 47: Yes, here I really feel at the centre, I am actually here.
Volunteer No. 51 indicated the location of the I-that-perceives in the belly:
Interviewer: Do you perceive the distinction between the sensation and the attention that perceives the sensation?
Volunteer No. 51: Well, here I feel [touches the chest] and here I have the attention [touches the belly]. […] I feel here as if my eyes were here [belly].
Interviewer: Which importance does this point hold?
Volunteer No. 51: It is myself.
This latter result, although different from the other volunteers that located the I-that-perceives in the head, also come from a progression up of the flow of perception and localization in first person of the source of perception.
Another interesting case is Volunteer No. 55, a volunteer with acquired blindness who lost his sight first from one eye and, over five or six years progressively also from the other.
Volunteer No. 55: The movement of my “I” is on the left eye. It’s like the left eye occupies this strange thing that we call “I”. Consider that I have lost my sight first with right eye as a child, while I lost the left eye when I was thirteen. My I is kind of a bit decentralized towards the eye that has seen longer. I feel the centre a little shifted towards the left.
Volunteer No. 55, going on in the interview, recognized that this “centre” was perceived “shifted” from a punctiform localization more original and concluded:
Volunteer No. 55: The seat of perception seems to have to do with sight, but it is the part behind the sight.
Five volunteers’ experience showed contradictions and inner discrepancies. Difficulties in the description have been observed as regards the distinction of subject and object inside the body.
Interviewer: Are there parts of your body that are additional with respect to your “I” and which could even not exist without compromising your “I”?
Interviewer: And then why do you say that your “I” coincides with your whole body?
Volunteer No. 8: I don’t know, I really have no idea.
In Volunteers No. 9 and No. 44 the main obstacle was the difficulty of distinguishing between the criterion of the “emotional distance” (how beautiful, how amazing, how suggestive) of the physical objects, and the criterion of distance at the physical level (distance in metres or centimetres).
Interviewer: Now bend your arm and tell me if the hand is closer or farther.
Volunteer No. 44: It is closer when the arm is stretched.
Volunteer No. 44: I don’t know, I feel it more mine, I feel it more.
Also with Volunteers No. 14 and No. 38 difficulties were observed in applying the criterion of physical distance, and a general difficulty in understanding the questions exactly.
Interviewer: Now try to stand up and feel the floor; as compared to when you were sitting, is it closer or farther?
Volunteer No. 14: Well, I feel it in the body, the floor, now, is a part of me.
Interviewer: Sit down now and try to tell me if you feel it closer or farther.
Volunteer No. 14: The sensation is different, I feel it, but I feel first the support of the chair and I am also more relaxed. I have a more widespread sensation and it is different from before.
We highlight that when different difficulties emerged, they were often linked to the entry into and persistence in thematic area number four, related to proprioception; perhaps because it is one of the less experienced phenomenological issues in everyday life.
A sixth volunteer (No. 35) without presenting any contradiction or descriptive inconsistency, denied the possibility of defining a location for the I-that-perceives.
Interviewer: If you consider the terms: “I” and “hand”, “I” and “knee”, “I” and “mouth”; is there a term that never changes?
Volunteer No. 35: I, but should I locate it?
Volunteer No. 35: I can’t locate it, I point to it but I cannot locate it.
Human volunteers generally seem to find it easy and natural to locate their centre of self, the place “I am” or the I-that-perceives. With considerable consistency, sighted or blind, Western or non Western, it is placed somewhere near the centre of their head. This seat corresponds to a “point zero”, the origin (0,0,0) point of a Cartesian spatial geometric framework, whose axes are defined by the subject’s experience of what lies close or far from him, in front or behind, up or below, where their sense of “I” and their sense of “here” are felt to coincide. At the same time this sense of “from where I perceive” remains always connected and distinct with respect to the phenomenological thereness of “what I perceive”. Thus this sense goes beyond an experience that can be reduced to a Cartesian dualism of subject and object: remaining faithful to the field of phenomenology and of direct experience, the point of departure of perception – a non-object – is reported to be inseparable from the objects perceived. It represents one “pole” of what might be called the bipolar monism of experience (Bertossa & Ferrari, 2002). This location is better understood within the context of attention, requiring what might be called the open pole of here-ness from which attentional experience originates, that complements the pole “terminal point of experience” (Velmans,1996, 2000a) to which attention is directed.
Conscious attention might require two spatial locations: one invariant from which attention always moves to the particular (and varying) entity to which it is directed. We cannot perceive the point of origin of perception, but we can point to that as a source of perception.
The question that now confronts us is: What does it mean to locate a “point zero” origin of perceptions? Why it is interesting and what does it help to understand? Point zero is a phenomenological datum widely shared and recognizable by volunteers naïve in phenomenological training; this seat is the reference point for conscious localization of all internal and external objects in space, involved during the execution of perceptual or self-referred tasks. Brain imaging studies can precisely locate of the brain areas actively metabolizing during these tasks: conscious self-related introspective processes have a clear localization in the lateral and medial prefrontal cortex, lateralized to the left hemisphere (Goldberg, Harel, & Malach, 2006); self-referential mental activity of judgment of pleasant/unpleasant matches increases in metabolic activity of the dorsal medial prefrontal cortex (Gusnard, Akbudak, Sulman, & Raichle, 2001). Kjar, Novack, & Lou (2002) in a PET imaging study observed that there are neural networks connecting precuneus, angular gyri and anterior cingulated gyri, associated with reflective “self-awareness”; this network is common to the resting conscious state, thus they proposed “self-awareness” as a core function of consciousness, representing a fundamental contribution to the contents and coherence of the conscious state.
Point zero can be involved also in making clear a person’s position not only in space and in actions, but also in time: memory research has investigated the subjective experience of past events wich enables us to travel back into our personal past (Tulving & Lepage, 2000). This awareness of one’s past – “autonoetic consciousness” – has neuroanatomical correlates: a memory retrieval task activates lateralized brain areas of the right prefrontal cortex, possibly extending posteriorly. From a first person perspective the past (and future) time-landscape of the I-that-perceives could be the subjective sense for the present duration (pole here/now) that complements the past-future self-representation (pole there/at that time).
The present study may serve as a model for a new approach to research on consciousness, giving a reliable reference map with nearly universal subjective features in naïve volunteers, in which time and space are integrated. The significance of the “point zero” of perception lies in the nature of the invariable point I, here, now, continually involved in moving through space and subjective time, and perhaps also through psychological crises or social relations. In future research we might ask, for example, whether the sense of the I-that-perceives is different in volunteers trained in phenomenological descriptions, and expands to ‘felt meanings’ (Petitmengin, 2007) and other features of subjective experience (Bertossa, Ferrari, & Besa, 2004) . Finally, it would be interesting to investigate if the I-that-perceives is altered – or even non-existent – in individuals with autism, or those classified with psychiatric disorders, in order to assess differences in their external spatial phenomenological perception related to the sense of self.
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