The Other in Me: Interpersonal Multisensory Stimulation Changes the Mental Representation of the Self

In the paper

“Interestingly, synchronous IMS resulted in a unidirectional change in the self-other distinction, affecting recognition of one’s own face, but not recognition of the other’s face.”

In the paper

“The participants’ autonomic responses to objects approaching the other’s face were higher following synchronous than asynchronous IMS, but this increase was not specific to the pattern of IMS in interaction with the viewed object.”

In the paper

“Finally, synchronous, as compared to asynchronous, IMS resulted in significant differences in participants’ ratings of their experience, but unlike other bodily illusions, positive changes in subjective experience were related to the perceived physical similarity between the two faces, and not to identification.”

In the paper

“The mean PSE values ± SE were, for the synchronous condition 45.91±1.55 (pre-test) and 48.81±1.71 (post-test), and for the asynchronous condition 46.22±1.43 (pre-test) and 45.36±1.67 (post-test).”

In the paper

“certain items did not result in affirmative ratings (Q3–6, Q10–12), while other items resulted in low yet affirmative values (Q1, Q2, Q7–9) following synchronous IMS.”

In the paper

“Arousal | 5.40 (2.0) | 5.04 (2.0) | 1.36 | .18”

In the paper

“but it should be noted that in our study the mean value for the critical statement Q3 (“I felt as if the other’s face was my face”) is numerically higher than the ones reported in previous studies [33], [34].”

What the sources say

• Not checked yetcites [33] A Sforza, 2010, My face in yours: Visuo-tactile facial stimulation influences sense of identity., Social Neuroscience source
• Not checked yetcites [34] M-P Paladino, 2010, Synchronous multisensory stimulation blurs self-other boundaries., Psychological Science source

In the paper

“In relation to changes in the subjective experience (Experiment 3), we observed a significant difference between the synchronous and asynchronous IMS, in line with other bodily illusions, but unlike other bodily illusions, only few statements resulted in positive affirmative ratings.”

In the paper

“Synchronous, as compared to asynchronous, IMS resulted in significant differences in participants’ ratings of their experience, but unlike other bodily illusions, the evidence for strong and positive changes in subjective experience was limited to a change in “touch referral” and the perceived physical similarity between the two faces.”

In the paper

“In addition, while certain statements resulted in negative ratings following both synchronous and asynchronous IMS (Q3, Q4 and Q6), the ratings between the synchronous and asynchronous conditions were significantly different, suggesting that participants showed less negation following synchronous IMS for these statements”

In the paper

“Following synchronous IMS, participants accepted statements referring to the source of tactile sensation (Q1, Q2) and the change in resemblance between the other’s face and their own face (Q7, Q8, Q9), while they denied the same statements following asynchronous IMS.”

In the paper

“This asymmetric effect for the two directions of morphing could also be observed in Experiment 1, but was not found in previous studies where the other’s face was a familiar one [32], [33].”

What the sources say

• Not checked yetcites [32] M Tsakiris, 2008, Looking for myself: Current multisensory input alters self-face recognition., PLoS One source
• Not checked yetcites [33] A Sforza, 2010, My face in yours: Visuo-tactile facial stimulation influences sense of identity., Social Neuroscience source

In the paper

“Synchronous IMS specifically affected recognition of the self-face, as statistically significant changes were observed only for the direction of morphing that presented a transition from other to self.”

In the paper

“Consistent with this pattern, our results show that morphed instances of the other’s face are perceived as self-stimuli, whereas morphed instances of the self-face are not perceived as other-stimuli.”

In the paper

“The ability to recognize oneself in a mirror is taken as evidence of a basic form of self-awareness in non-human primates [1], [3] and human infants [4].”

What the sources say

• Not checked yetcites [1] GGJ Gallup, 1970, Chimpanzees: Self-Recognition., Science source
• Not checked yetcites [3] FB de Waal, 2005, The monkey in the mirror: Hardly a stranger., Proceedings of the National Academy of Sciences of the United States of America source
• Not checked yetcites [4] BI Bertenthal, 1978, Development of self-recognition in the infant., Child Development

In the paper

“Changes in autonomic responses and in the subjective experience of self-identification were broadly consistent with patterns observed in other bodily illusions, but less robust.”

In the paper

“For example, Uddin et al. [11] reported activations in the right inferior parietal lobule, inferior frontal gyrus and inferior occipital gyrus.”

What the sources say

• Not checked yetcites [11] LQ Uddin, 2004, Self-face recognition activates a frontoparietal “mirror” network in the right hemisphere: an event-related fMRI study., NeuroImage

In the paper

“This ability for self-face recognition is also claimed to be fundamental to the awareness of being a self among others like us [5], upon which more complex forms of self-identity are built, such as a diachronic sense of self [6], and the expression of social emotions (e.g., embarrassment, pride and guilt [7]).”

What the sources say

• Not checked yetcites [5] D Zahavi, 2011, Faces and ascriptions: mapping measures of the self., Conscious & Cognition source
• Not checked yetcites [6] DJ Povinelli, 1998, Young children's understanding of briefly versus extremely delayed images of self: Emergence of the autobiographical stance., Developmental Psychology source
• Not checked yetcites [7] M Lewis, 2006, The emergence of consciousness and its role in human development., Annals of the New York Academy of Sciences source

In the paper

“Accumulating evidence favors a right hemispheric specificity in frontoparietal areas responsible for self-face recognition [8].”

What the sources say

• Not checked yetcites [8] SJ Gillihan, 2005, Is self special? A critical review of evidence from experimental psychology and cognitive neuroscience., Psychological Bulletin source

In the paper

“Overall, shared multisensory experiences between self and other can change the mental representation of one’s identity, and the perceived similarity of others relative to one’s self.”

In the paper

“Mirror self-recognition is a key feature of self-awareness and identity [1], [2].”

What the sources say

• Not checked yetcites [1] GGJ Gallup, 1970, Chimpanzees: Self-Recognition., Science source
• Not checked yetcites [2] P Rochat, 2011, The uncanny mirror: A re-framing of mirror self-experience., Consciousness & Cognition source

In the paper

“In the rubber hand illusion (RHI), synchronous visuo-tactile stimulation between a rubber hand and one’s own unseen hand generates the feeling that the rubber hand is part of one’s body [25].”

What the sources say

• Not checked yetcites [25] M Botvinick, 1998, Rubber hands ‘feel’ touch that eyes see., Nature source

In the paper

“This task, in which participants were required to give judgments for single pictures, without being aware of the direction of change from one picture to the other, avoids potential errors of habituation and/or anticipation due to cognitive expectations [36].”

What the sources say

• Not checked yetcites [36] TS Meese, 1995, Using the standard staircase to measure the point of subjective equality: A guide based on computer simulations., Perception & Psychophysics source

In the paper

“These findings are compatible with the behavioral results of Tsakiris [32] and Sforza et al. [33], but importantly, they show, for the first time, that IMS between one’s own face and a completely unknown face can affect the mental representation of one’s own face.”

What the sources say

• Not checked yetcites [32] M Tsakiris, 2008, Looking for myself: Current multisensory input alters self-face recognition., PLoS One source
• Not checked yetcites [33] A Sforza, 2010, My face in yours: Visuo-tactile facial stimulation influences sense of identity., Social Neuroscience source

In the paper

“Behavioral research emphasizes the role of mnemonic representations of one’s face [17]–[21], suggesting that I recognize myself in the mirror because I know the person I see looks like me.”

What the sources say

• Not checked yetcites [17]–[21]

In the paper

“Similar effects were reported in the description of the “enfacement illusion” by Sforza et al. [33], who used exposure to visuo-tactile stimulation delivered to the participant’s face and, unlike Tsakiris [32], the familiar face of a friend or colleague who was physically present.”

What the sources say

• Not checked yetcites [33] A Sforza, 2010, My face in yours: Visuo-tactile facial stimulation influences sense of identity., Social Neuroscience source

In the paper

“Sforza et al. [33] used a familiar face during visuo-tactile stimulation and lacked a baseline self-recognition task prior to stimulation;”

What the sources say

• Not checked yetcites [33] A Sforza, 2010, My face in yours: Visuo-tactile facial stimulation influences sense of identity., Social Neuroscience source

In the paper

“rTMS over the right TPJ, but not over the left TPJ, biased self-other discrimination but only in the “other to self” direction of morphing, without any effect on the “self to other” direction of morphing.”

What the sources say

• Not checked yetcites [16] C Heinisch, 2010, An rTMS study into self-face recognition using video-morphing technique., Social Cognitive and Affective Neuroscience

In the paper

“Comparable findings have been shown after multisensory stimulation of whole bodies [26]–[29] and in the body-swap illusion [30].”

What the sources say

• Not checked yetcites [26]–[29]
• Not checked yetcites [30] VI Petkova, 2008, If I were you: Perceptual illusion of body swapping., PLoS ONE source

In the paper

“EDA is a sensitive and valid indicator for the low arousal range, reflecting small variations in response to arousing stimuli [40], while heart rate deceleration (HRD) is a valid real-time measure for the higher arousal range and attention.”

What the sources say

• Not checked yetcites [40] W Boucsein, 1992, Electrodermal activity. source

In the paper

“When people experience ownership over a foreign body, as a result of multisensory stimulation, they also exhibit increased physiological responses to threatening stimuli approaching the body that is attributed to the self [30].”

What the sources say

• Not checked yetcites [30] VI Petkova, 2008, If I were you: Perceptual illusion of body swapping., PLoS ONE source

In the paper

“To further investigate the causal role of these areas in self-other discrimination, Uddin et al. [15] used repetitive transcranial magnetic stimulation (rTMS) over the right inferior parietal lobe (rIPL), which selectively disrupted performance on a self-other discrimination task, whereas rTMS to the left IPL had no effect.”

What the sources say

• Not checked yetcites [15] LQ Uddin, 2006, rTMS to the right inferior parietal lobule disrupts self-other discrimination., Social Cognitive and Affective Neuroscience source

In the paper

“Devue et al. [12] reported that visual self-recognition of both faces and bodies activated the right inferior frontal gyrus and the right insula (see also [13], [14]).”

What the sources say

• Not checked yetcites [12] C Devue, 2007, Here I am: The cortical correlates of visual self- recognition., Brain Research source
• Not checked yetcites [13] TTJ Kircher, 2001, Recognizing one’s own face., Cognition source
• Not checked yetcites [14] LQ Uddin, 2005, Split-brain reveals separate but equal self-recognition in the two cerebral hemispheres., Consciousness & Cognition source

In the paper

“Extending the behavioral results of Tsakiris [32] and Sforza et al. [33], Paladino et al. [34] exposed participants to visuo-tactile stimulation delivered to their face and another unfamiliar face, and showed that synchronous multisensory stimulation might also influence social cognition processes of inference and conformity, and the perceived physical resemblance between one’s own and the other’s”

What the sources say

• Not checked yetcites [34] M-P Paladino, 2010, Synchronous multisensory stimulation blurs self-other boundaries., Psychological Science source

In the paper

“Previous research from similar bodily illusions (RHI) suggests that on average the illusion onset takes place approximately after 12 s of stimulation [39].”

What the sources say

• Not checked yetcites [39] HH Ehrsson, 2004, That's my hand! Activity in premotor cortex reflects feeling of ownership of a limb., Science source

In the paper

“and Paladino et al. [34] lacked a behavioral self-recognition task and did not control for the gender of the viewed model.”

What the sources say

• Not checked yetcites [34] M-P Paladino, 2010, Synchronous multisensory stimulation blurs self-other boundaries., Psychological Science source

In the paper

“The first psychophysical task (Experiment 1) was designed to minimize the effect of cognitive expectations on the performance of the self-recognition task.”

In the paper

“changes in EDA are not as immediate as those in heart response, but they normally occur between 1 and 2 s after stimulus onset, although the response can be delayed up to 5 s [45].”

What the sources say

• Not checked yetcites [45] R Edelberg, 1967, Electrical properties of the skin.

In the paper

“Experiment 4 shows that synchronous visuo-tactile stimulation altered self-face representations, by producing changes in the recognition of the self-face, while recognition of the other’s face was not affected.”

In the paper

“This issue was investigated by Tsakiris [32] and Sforza et al. [33], who failed to find significant differences between self-recognition changes for the “self to other” and “other to self” directions [32] and between the judgments given under different instruction conditions (e.g., to evaluate the amount of “self” or to evaluate the amount of “other” contained in the morphs) [33].”

What the sources say

• Not checked yetcites [32] M Tsakiris, 2008, Looking for myself: Current multisensory input alters self-face recognition., PLoS One source
• Not checked yetcites [33] A Sforza, 2010, My face in yours: Visuo-tactile facial stimulation influences sense of identity., Social Neuroscience source

In the paper

“These results might also indicate a specific change in the perceived similarity of the other face relative to self, but not the reverse, as discussed below.”

In the paper

“the experience of seeing a knife is generally significantly more arousing than the experience of seeing a spoon (e.g., [47])”

What the sources say

• Not checked yetcites [47] PJ Lang, 2008, International affective picture system (IAPS): Affective ratings of pictures and instruction manual. Technical Report A-8.

In the paper

“The observed changes in HRD might reflect the general modulation of attention of visuo-tactile stimulation, independent of the kind of object that appeared, with synchronous IMS resulting in greater HRD.”

In the paper

“None of the factors passed the normality test, therefore we used non-parametrical statistical tests to analyze the data (Wilcoxon Signed Ranks Test).”

In the paper

“Previous studies on the RHI have reported changes in the perceived similarity between felt and seen bodies whereby the rubber hand is perceived to become more similar to one’s own hand [24], [49].”

What the sources say

• Not checked yetcites [24] MR Longo, 2009, Self awareness and the body image., Acta Psychologica source
• Not checked yetcites [49] MR Longo, 2008, What is embodiment? A psychometric approach., Cognition source

In the paper

“This change was similar but subjectively not as strong as those changes observed in other body-illusions that use multisensory stimulation to manipulate body-awareness [24], [49].”

What the sources say

• Not checked yetcites [24] MR Longo, 2009, Self awareness and the body image., Acta Psychologica source
• Not checked yetcites [49] MR Longo, 2008, What is embodiment? A psychometric approach., Cognition source

In the paper

“although it seems that other bodily illusions (e.g., RHI) produce stronger phenomenological effects, as reported by participants.”

What the sources say

• Not checked yetcites [49] MR Longo, 2008, What is embodiment? A psychometric approach., Cognition source

In the paper

“Experiment 1 was designed to control for potential confounds reported in previous studies, such as the use of a familiar face [32], [33] and the lack of a pre-test baseline self-recognition performance [33].”

What the sources say

• Not checked yetcites [32] M Tsakiris, 2008, Looking for myself: Current multisensory input alters self-face recognition., PLoS One source
• Not checked yetcites [33] A Sforza, 2010, My face in yours: Visuo-tactile facial stimulation influences sense of identity., Social Neuroscience source

In the paper

“The observed larger HRD during synchronous, as compared to asynchronous, IMS, might reflect an increase in attention [41] towards the other’s face.”

What the sources say

• Not checked yetcites [41] PJ Lang, 1990, Emotion attention and the startle reflex., Psychological Review source

In the paper

“In addition, the overall affirmative ratings in questions relating to the perceived similarity of the other’s face (see Q7–9) following synchronous IMS point to a key change in subjective experience and are consistent with the behavioral pattern as discussed below.”

In the paper

“These items are important as they reflect the subjective experience of a key process of “touch referral” that has been implicated in the inducement of similar bodily illusions [53].”

What the sources say

• Not checked yetcites [53] TR Makin, 2008, On the other hand: Dummy hands and peripersonal space., Behavioural Brain Research source

In the paper

“which shows that the increase in arousal is threat-related and not only due to the general effect of seeing an object approaching the face after synchronous IMS.”

In the paper

“Overall, this pattern is consistent with the reported changes in subjective experience in other studies reporting the influence of multisensory stimulation in face recognition [33], [34]”

What the sources say

• Not checked yetcites [33] A Sforza, 2010, My face in yours: Visuo-tactile facial stimulation influences sense of identity., Social Neuroscience source
• Not checked yetcites [34] M-P Paladino, 2010, Synchronous multisensory stimulation blurs self-other boundaries., Psychological Science source

In the paper

“This concern identifies a potential confound that requires an additional control condition with synchronous IMS but without changes in face representation.”

In the paper

“That would be analogous to the one used in the rubber hand illusion where, for example, synchronous multisensory stimulation is applied to a rubber hand that is placed in an incongruent posture with respect to the participant’s hand, a condition that does not elicit ownership [52].”

What the sources say

• Not checked yetcites [52] A Guterstam, 2011, The illusion of owning a third arm., PLoS ONE source

In the paper

“These were the ones that focused mainly on the perceived physical similarity between self and other, corroborating thus the behavioral findings.”

In the paper

“It should be noted that a previous study which measured HRD in response to a person being threatened, observed from first- and third-person-perspective, did not find a significant difference in HRD to the threat occurring after synchronous as compared to the asynchronous touch condition, but they only found differences in HRD between the conditions when the person threatened was observed from first”

What the sources say

• Not checked yetcites [51] M Slater, 2010, First person experience of body transfer in virtual reality., PLoS ONE source

In the paper

“Therefore, despite the lack of a significant interaction, these planned contrasts provide some tentative support for an effect of synchronous IMS on autonomic reactivity related to stimuli, and perhaps more so for threatening stimuli, approaching the other’s face.”

In the paper

“For example, during synchronous IMS, a strong binding between one’s own tactile experiences and the visual impact on the other face results in increased attention to the other face, which can in turn explain the higher EDA responses as confirmed by the significant main effect of stimulation.”

In the paper

“For example, it has been found that when the two end-points of a continuum are the self-face and an unknown face, the categorical boundaries are dependent on the perceived face similarity between self and other but not on the direction of morphing [13], [54]–[56].”

What the sources say

• Not checked yetcites [13] TTJ Kircher, 2001, Recognizing one’s own face., Cognition source
• Not checked yetcites [54]–[56]

In the paper

“Previous studies failed to find significant differences between self-recognition changes for the “self to other” and “other to self” directions in a video morphing from one face to the other [32], a task identical to the one used in our Experiment 4, and between the judgments of morphed images under different instruction conditions (either to evaluate the amount of “self” or to evaluate the amount”

What the sources say

• Not checked yetcites [32] M Tsakiris, 2008, Looking for myself: Current multisensory input alters self-face recognition., PLoS One source
• Not checked yetcites [33] A Sforza, 2010, My face in yours: Visuo-tactile facial stimulation influences sense of identity., Social Neuroscience source

In the paper

“Heinisch et al. [16] argued that disrupting neural processing in rTPJ makes self-recognition performance less conservative (i.e., increasing the likelihood of accepting other faces as one’s own face), while other-face recognition is unaffected (i.e., the likelihood of judging one’s own face as that of someone else is not changing).”

What the sources say

• Not checked yetcites [16] C Heinisch, 2010, An rTMS study into self-face recognition using video-morphing technique., Social Cognitive and Affective Neuroscience

In the paper

“Aside from the rTMS study over the rTPJ that showed an asymmetric effect on categorical boundaries depending also on the direction of morphing [16], we show that synchronous IMS can also elicit an asymmetric effect, such that the other’s face is perceived as self-face, while the reverse did not occur.”

What the sources say

• Not checked yetcites [16] C Heinisch, 2010, An rTMS study into self-face recognition using video-morphing technique., Social Cognitive and Affective Neuroscience

In the paper

“It has been suggested that the perceived similarity of other people to one’s self is the starting point for inferring that others have similar psychological processes, including perceptions and emotions, as one’s self (see the “like me” process [57]).”

What the sources say

• Not checked yetcites [57] AN Meltzoff, 2007, 'Like me': A foundation for social cognition., Developmental Science source

In the paper

“Our results provide further support to these theories because following synchronous IMS, the “other” is perceived to be more “like me”.”

In the paper

“Here, we used an unfamiliar face, and synchronous IMS seems to reverse this pattern by shifting categorical boundaries towards the unfamiliar face, suggesting that a higher percentage of the other face is assimilated in the mental representation of the self-face.”

In the paper

“Moreover, this change depends on the interaction of the pattern of stimulation and the direction of morphing (Experiment 4), that makes the other’s face to be perceived as self-face.”

In the paper

“Insula activations in the right hemisphere have been reported during bodily illusions of body-ownership caused by multisensory integration [61], as well as during self-face recognition [12], and the mapping of observed bodily states on one’s own body [62].”

What the sources say

• Not checked yetcites [61] M Tsakiris, 2007, Neural signatures of body ownership: a sensory network for bodily self-consciousness., Cerebral Cortex source
• Not checked yetcites [12] C Devue, 2007, Here I am: The cortical correlates of visual self- recognition., Brain Research source
• Not checked yetcites [62] T Singer, 2004, Empathy for pain involves the affective but not sensory components of pain., Science source

In the paper

“Uddin et al. [59] suggest that there are at least two neural networks involved in representing self and others.”

What the sources say

• Not checked yetcites [59] LQ Uddin, 2007, The self and social cognition: the role cortical midline structures and mirror neurons., Trends in Cognitive Sciences source

In the paper

“This mapping may also depend on the perceived physical similarity between self and other [65].”

What the sources say

• Not checked yetcites [65] A Avenanti, 2010, Racial bias reduces empathic sensorimotor resonance with other-race pain., Current Biology source

In the paper

“For example, Paladino et al. [34], using an experimental paradigm similar to ours, showed that IMS altered the social perception of participants towards the other person: following synchronous vs. asynchronous IMS, participants reported a higher self-other merging measured in terms of inner states, closeness and physical attraction, and they tended to conform more with the other.”

What the sources say

• Not checked yetcites [34] M-P Paladino, 2010, Synchronous multisensory stimulation blurs self-other boundaries., Psychological Science source

In the paper

“This model provides a functional explanation of how the “I” comes to be identified with “me”, allowing this “me” to be represented as an object for the others, but also for one’s own self.”

In the paper

“Evidence for changes in autonomic responses and in the subjective experience of self-identification were broadly consistent with patterns observed in other bodily illusions, but they were not as potent.”

In the paper

“The frontoparietal mirror neuron system (MNS), which is involved in processing the physical self [11], and a network composed of the cortical midline structures (CMS) including the medial prefrontal cortex, the anterior cingulate cortex and the precuneus which is involved in the more abstract, evaluative processing of self and others.”

What the sources say

• Not checked yetcites [11] LQ Uddin, 2004, Self-face recognition activates a frontoparietal “mirror” network in the right hemisphere: an event-related fMRI study., NeuroImage

In the paper

“Finally, the right TPJ has been shown to engage in the filtering of multisensory percepts that may be assigned to one’s own body or not [63] and in the maintenance of a 1st person perspective [64].”

What the sources say

• Not checked yetcites [63] M Tsakiris, 2008, The role of the right temporo-parietal junction in maintaining a coherent sense of one's body., Neuropsychologia source
• Not checked yetcites [64] S Ionta, 2011, Multisensory mechanisms in temporo-parietal cortex support self-location and first-person perspective., Neuron source

In the paper

“These results suggest that self-other distinction and recognition of the physical self might be based upon specific processes of multisensory perception.”

In the paper

“For example, Ishida et al. [60] showed that visuo-tactile neurons in the parietal cortex display mirroring properties and can be used to link self and other body representations.”

What the sources say

• Not checked yetcites [60] H Ishida, 2010, Shared mapping of own and others' bodies in visuotactile bimodal area of monkey parietal cortex., Journal of Cognitive Neuroscience source

In the paper

“This change in perceived similarity is caused by the synchrony of multisensory stimuli, which in the context of body-awareness has been shown to determine whether external stimuli can be experienced as part of the self or not [25].”

What the sources say

• Not checked yetcites [25] M Botvinick, 1998, Rubber hands ‘feel’ touch that eyes see., Nature source

In the paper

“Multisensory integration provides a plausible mechanism for constructing a self-representation, and for the subsequent assimilation of changes and updating of self-representations.”