Since the beginning of the twentieth Century, phenomenology has developed a distinction
between lived body (leib) and physical body (koerper), a distinction well known as
body-subject vs. body-object (Hanna and Thompson, 2003). The lived body is the body
experienced from within—my own direct experience of my body lived in the first-person
perspective, myself as a spatiotemporal embodied agent in the world. The physical
body on the other hand, is the body thematically investigated from a third person
perspective by natural sciences such as anatomy and physiology.
An active topic affecting the understanding of several psychopathological disorders
is the relatively unknown dynamic existing between aspects related to the body-object
(that comprises the neurobiological substrate of the disease) and the body-subject
(the experiences reported by patients) (Nelson and Sass, 2017). A clue testifying
the need to better explore this dynamic in the psychopathological context is the marked
gap that still exists between patients' clinical reports (generally entailing disturbing
experiences) and etiopathogenetic theories and therapeutic practices, that are mainly
postulated at a bodily/brain level of description and analysis. The phenomenological
exploration typically targets descriptions of persons' lived experience. For instance,
patients suffering from schizophrenia may describe their thoughts as alien (“thoughts
are intruding into my head”) and the world surrounding them as fragmented (“the world
is a series of snapshots”) (Stanghellini et al., 2015a). The result is a rich and
detailed collection of the patients' qualitative self-descriptions (Stanghellini and
Rossi, 2014), that reveal fundamental changes in the structure of experiencing and
can be captured by using specific assessment tools (Parnas et al., 2005; Stanghellini
et al., 2014; Sass et al., 2017).
The practice of considering the objective and the subjective levels of analysis as
separated in the research studies design has many unintended consequences. Primarily,
it has the effect of limiting actionable neuroscientific progress within clinical
practice. This holds true both in terms of availability of evidence-based treatments
for the disorders, as well as for early diagnosis purposes. In response to this need,
this collection of articles aims to promote an interdisciplinary endeavor to better
connect the bodily, objective level of analysis with its experiential corollary. This
is accomplished by focusing on the convergence between (neuro) physiological evidence
and the phenomenological manifestations of anomalous bodily experiences present in
different disorders. Still indeed, little effort has been channeled in order to plan
comprehensive research protocols that include aspects derived from the lived world
of patients.
The idea of addressing the human body going beyond the simple Hippocratic idea is
revitalized in the concept of Embodied Medicine proposed by Riva et al. Body representation
is a complex aspect, as it involves the encoding and integration of a wide range of
multisensory—somatosensory, visual, auditory, vestibular, visceral—and motor signals
(Blanke, 2012). Specifically for self-bodily recognition, behavioral and anatomical
data suggest that implicit and explicit routes for self-body knowledge are dissociated
and mediated by different cerebral networks at a brain level (Candini et al.). The
concept of Embodied Medicine takes advantage from the multisensory nature of the body
and promote the use of advanced technologies for altering the experience of being
in a body, with the goal of improving health and well-being. In particular, the technology
proposed by Riva et al. works as a means to modify the inner body for treating different
neurological and psychiatric diseases and their phenotypical manifestations. The commentary
of Pistoia et al. in this respect, illustrates other potential applications of this
technology specifically in the context of neurological disorders like the Locked-in
Syndrome.
The contribution from Northoff and Stanghellini outlines an experimentally testable
hypothesis meant to provide converging evidence from psychopathological facts (phenomenology,
see Stanghellini et al., 2014) and neurophysiological measures in schizophrenia. This
is accomplished by combining temporal measures of the brain's spontaneous activity
of interoceptive stimuli and temporal measures for the subjective experience of the
body. Along similar lines, the work of Ebisch et al. supports the existence of a brain
network processing the integration of information derived from multiple sources during
social perception. Authors here hypothesize that such integrative processing of social
information occurring at a brain level might be mediated by the linking of external
stimuli with self-experience.
An empirical attempt to find a common structure that integrates intero- and exteroceptive
stimuli processing can be found in other articles included in this collection. In
their study, Ardizzi et al. consider the individual sensitivity to detect the visceral
sensations originating inside of the body (i.e., interoception accuracy) as a facet
of self-integrity in schizophrenia. The results report a reduced sensitivity in patients
to their inner bodily signals, that correlates with positive symptoms severity.
Numerous studies show that interoception is altered in different psychiatric disorders.
For example, low interoceptive accuracy was established in anorexia nervosa (Pollatos
et al., 2008; Stanghellini et al., 2012, 2015b; Gaudio et al., 2014), major depression
(Furman et al., 2013; Harshaw, 2015) and depersonalization- derealization disorders
(Sedeño et al., 2014). Ambrosecchia et al. report how interoception and autonomic
regulation are modulated during social interactions in a population of restrictive
anorexia nervosa patients. Authors suggest that an autonomic imbalance and its altered
relationship with interoception might have a key role in emotional and social disposition
manifestations of the disorder. In their article, Pollatos et al. report how anorexia
patients show a significant decrease of interoceptive accuracy during self-focus sessions,
a therapeutic practice aimed at increasing attention to patients' own bodily features.
This study provides insights into phenomenological aspects related to body-avoidance
feelings that characterize anorexia, and draws attention to possible implications
for treatment.
Anomalous bodily experiences may also accompany a number of chronic pain conditions.
The work from Tajadura-Jiménez et al. describes how acoustic sensory feedback can
alter humans' body perception and the pain experienced, suggesting potential practical
applications in the clinical setting. In their study, Valenzuela-Moguillansky et al.
highlight possible interactions between exteroceptive and interoceptive self-body
awareness aspects in patients suffering from fibromyalgia. Authors then relate these
aspects to pain, suggesting suitable therapeutic practices tapping into this interaction.
Specifically in the context of schizophrenia, however, genetics still remain a crucial
risk factor. The work of Henriksen et al. reviews the state of the art of the complex
genetic architecture of schizophrenia and related phenotypes evident in clinical practice.
Empirical research on anomalous self-experiences reported by patients with schizophrenia
(Parnas and Handest, 2003) indeed, considers this aspect to be an intermediate phenotype
of the disorder. Investigating the neurophysiological correlates of anomalous self-experience
became a topic of intense research. Some studies for example, point toward a disturbance
of emotional motor resonance and multisensory integration as body-level correlates
of anomalous self-experience in schizophrenia (Sestito et al., 2013, 2015a,b; Gallese
and Ferri, 2014; Ebisch and Gallese, 2015). In this respect, the explorative study
conducted by Sestito et al. provide support for a complex interaction between anomalous
self-experiences and psychotic symptoms in the context of neutral stimuli misperception
in schizophrenia. These preliminary findings outline some testable perspectives on
the connection between molecular neurochemistry of delusions formation at a brain
level and their psychopathological corollary. Gallager and Trigg illustrate the relevance
of phenomenological accounts of schizophrenia and agoraphobia, highlighting the importance
of considering the interdependent nature of neural aspects, subjective experience,
and social environment. In the work of Haug et al., results describe how anomalous
self-experiences might be a useful target in other psychopathological conditions like
depression, to assist the clinician in understanding patients' experience of self-esteem
to prevent suicidality. Taken together, these studies show the potential of applying
anomalous self-experiences as a target phenotype for neurobiological and genetic research
in the context of schizophrenia and other psychopathological diseases.
Further theoretical efforts directed at exploring the connections between anomalous
self-experiences and the brain substrate are presented in the works of Kuang and Jalal
and Ramachandran. The paper of Kuang proposes a unified social motor cognition theory
in order to conceal the neural and the mental levels of cognitive processing in the
context of the mirror-touch synaesthesia manifestations. The neural level is herein
considered the physical process regarding basic sensory-motor aspects of the action,
which supports motor imitation and goal understanding (i.e., the Mirror Neuron System,
MNS) whereas, the mental level concerns the attribution of mental states, which supports
inferring others' minds and self-other distinctions. In the work of Jalal and Ramachandran
for example, the MNS substrate is suggested to play a role in giving rise to a particular
sort of out of body experiences occurring during the REM sleep. Such experiences include
sensing and seeing the presence of threatening intruders in one's bedroom—the so called
“ghostly bedroom intruder” experience. According to these authors, in this condition
the activation of the MNS would enable to see the world from an allocentric perspective,
without leaving one's own body.
Further efforts are needed to indentify comprehensive protocols capitalizing upon
the integration between the phenomenological and the (neuro) physiological levels
of analysis. In this respect, the embodied cognition approach—considering the MNS
as a neural substrate—offers an insightful perspective to inspire future research
protocols aimed at bridging the body-object and the body-subject. To pursue this endeavor,
it will be critical to unravel the (neuro) physiological mechanisms enabling the integration
between inner body signals and exteroceptive inputs. The topic “Embodying the self:
neurophysiological perspectives on the psychopathology of anomalous bodily experiences”
is a very active research topic that has a major importance in providing advances
for intervention approaches and for the understanding of vulnerability markers to
enhance early identification of psychopathological diseases.
Author contributions
MS: Intellectual conceptualization, literature review, and manuscript drafting. AR:
Intellectual conceptualization and literature review. GS: Literature review. VG: Intellectual
conceptualization, literature review, and manuscript drafting supervision. All the
authors contributed to the final revision of the manuscript.
Conflict of interest statement
The authors declare that the research was conducted in the absence of any commercial
or financial relationships that could be construed as a potential conflict of interest.