Ecole Polytechnique Fédérale de Lausanne

Multisensory brain mechanisms of bodily self- Olaf Blanke

http://lnco.epfl.ch/ http://cnp.epfl.ch/ Laboratory of Cognitive Center for Neuroprosthetics What is a Self ?

The self seems distinct from the environment and other humans and may be described as an entity to which certain mental events and actions are ascribed. [David & Kircher, 2003]

The Self in

Autobiographical Memory

Thought: Cogito Ergo Sum

Visual Mirror Recognition

Bodily self-consciousness: How the brain processes signals from the body is the foundation for the self Jeannerod, Frith, Ramachandran Damasio, Craig Bodily self (consciousness) without a body Phantom limbs

The physical body is NOT necessary for the experience of the bodily self.

Melzack proposed “that the brain generates the experience of the body and that sensory inputs merely modulate our bodily experience.”

Phantom limbs are “produced by the same brain processes that underlie the experience of the body when it is intact”

[Halligan, 2002; Melzack, 1990; Ramachandran, 1993; Brugger et al., 2000] Bodily self for the entire body Are there phantom bodies and phantom selves?

Out-of-body experiences: abnormal bodily self- consciousness

Extracorporeal Self-location (or disembodiment) I am localized outside my body Extracorporal first-person perspective I perceive the world (and my body) from a disembodied perspective Self-identification I identify with the elevated body of out-of-body experiences Brain damage is localized in right superior temporal gyrus/angular gyrus

-OBEs are illusory own body perceptions -Brain damage centers in temporo-parietal junction -Brain damage leads to double disintegration of multisensory bodily information ( Visual-tactile-proprioceptive signals and visuo-vestibular signals) [Devinsky et al., Arch Neurol 1989; Brugger, Neuropsychiatr 2002; Blanke et al., Nature 2002; Brain 2004; Ionta et al., Neuron 2011] Manipulating Self-location and Self-identification in healthy subjects

Video ergo sum Self-consciousness & visuo-tactile integration: The rubber hand illusion

[see also video on youtube: « Virtual rubber hand illusion »] A fake arm feels like my arm and is associated with abnormal arm localization ~The rubber hand illusion~ Arm position recalibration

Questionnaire responses « I feel the touch where I see the touch » « The fake hand feels like my real hand »

[Botvinick and Cohen, 1998; Armel & Ramachandran, 2003; Ehrsson et al., 2005; Tsakiris & Haggard, 2005; Evans & Blanke, NeuroImage 2012] From hand to body: Projecting the bodily self to a fake body

Subject with Head Mounted Display (covered)

Video camera with 3-D converter

Virtual body

2m

Actual body

[Lenggenhager et al., Science 2007] Embodiment of virtual and artificial bodies A virtual or filmed body feels like my body and “I” am localized at the virtual body’s position

Self-identifcation Self-location

anterior shift

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 Position Questionnaire Recalibration

[Lenggenhager et al., 2007] [youtube: « Virtual out-of-body experience »] Laboratory of Cognitive Neuroscience These changes in self-consciousness are body specific, change touch perception, and decrease pain

 [Aspell et al., 2009; 2010]  [Ehrsson, 2007; Petkova and

Ehrsson, 2008]

Study 2 [Lenggenhager et al., 2007]

   



    

Increase in pain thresholds EEG &

[Palluel et al., J Neurophysiol, 2011; Hänsel et al., 2011] Laboratory of Cognitive Neuroscience The brain mechanisms of bodily self- consciousness: Neuroscience robotics Body condition Control condition

Self-location Synchronous/asynchronous

[Ionta et al., Neuron 2011; Duenas et al., IEEE 2012; Pfeiffer et al., POne 2013] Activity in right and left posterior superior temporal gyrus reflects self-location that depends on the first-person perspective

[Ionta et al., 2011] Laboratory of Cognitive Neuroscience Pathologically & experimentally induced changes in bodily self-consciousness converge onto bilateral (right) temporo-parietal cortex

VLSM

 TPJ activity (within a network of related brain regions) reflects one of the most fundamental subjective feelings in humans: Self-location and first-person perspective Bodily self-consciousness brain mechanisms extend beyond temporo-parietal cortex Self-related fc fMRI Self location dependant fc fMRI

  Functional connectivity between the right and the left TPJ with the right insula (and right medial prefrontal cortex) reflects self-location and 1PP [Ionta et al., submitted] The Self in Cognitive Neuroscience

Autobiographical Memory

Thought: Cogito Ergo Sum

Visual Mirror Recognition

Bodily self-consciousness: How the brain processes signals from the body is the foundation for the self Jeannerod, Frith, Ramachandran Damasio, Craig Bodily self-consciousness based on exteroceptive bodily cues versus interoceptive cues Visceroception and the insula

AIC MIC PIC

[Damasio, 2000; Critchley et al., Nat Neurosci 2004; Craig, Nat Neurosci Rev 2002, 2009] Do exteroceptive (i.e. visuo-tactile) and interoceptive cues interact and affect bodily self-consciousness? Conflict between interoceptive (heart) and exteroceptive (visual) signals: Online detection of QRS complex was used to illuminate an avatar synchronously and asynchronously with one’s own heartbeat (cardio-visual conflict)

- Cardio-visual illumination of the avatar - a flashing silhouette around the avatar was either sync or asnyc with respect to the participant’s heartbeat (QRS) [Aspell et al., Psychological Science 2013] Turning body and self inside out: Visualized heartbeats alter self-identification and self- location Self-identifcation Self-location

Position Questionnaire Recalibration - Body-specific and synchrony dependant changes in self identification and self- location - Participants were not aware of the heartbeat manipulation (middle) and this did not differ among exp. conditions Cardiac signals converge with visual & tactile signals and alter a late SEP component (insula?) Synchrony dependent changes in sthe visuo-tactile crossmodal congruency effect

P45 differs between snyc and async cardio-visual illumination

P45 amplitude correlates with self-identification

[Heydrich, et al., submitted] Laboratory of Cognitive Neuroscience [Heydrich and Blanke, Brain 2013] What is Self-consciousness ?  [Ionta et al., in revision] Working hypothesis: The conscious experience of being this entity (of being a person) is caused by brain activity during spatially congruent self-identification, self-location and first-person perspective. This is based on a bottom-up body representation based on the integration of specific somatosensory-vestibular- visual and interoceptive signals in areas VIP, PIVC, MST, and insula. 1- Bodily self-consciousness as the foundation of the many-dimensional Self (and the Person)

•Visual Recognition: Recognizing one's image in a mirror •Memory: Autobiographical memory •Language : first-person pronouns, self-narrative •Social: ability to adapt the perspective of the other to oneself, •Thought : Ability to think “I” thoughts; ability to think of oneself as oneself, have a self concept, “to know that I know” •… 2- Although self-consciousness is often regarded as the greatest mystery in science (and consciousness studies), it may turn out to be less complex than we think and less complex than consciousness. Ecole Polytechnique Fédérale de Lausanne

Thank you!

http://lnco.epfl.ch/ Center for Neuroprosthetics http://cnp.epfl.ch/ EPFL

Self-location depends on the experienced direction of the first-person perspective

Up-Lookers [Q1: Did you have the Down-Lookers impression to look up at (n=11) the body above you or down at the body below sync. stimulation leads to you?] opposite drift in self-location in up- and down-lookers “towards (n=11) the virtual body”) The experienced direction of the first-person perspective can be manipulated by a visuo-vestibular conflict

Visuo-tactile-proprioceptive integration (visuo-vestibular integration) Hand and Trunk-centered trimodal neurons in parietal and frontal cortex

Visual receptive fields Tactile receptive fields

[Iriki et al., Neuroreport 1996; Graziano et al., Science 2000; Duhamel et al., J Neurophysiol 1998; Blanke, Nat Rev Neurosci 2012] Interoceptive out-of body experiences (Heautoscopy): Statistical lesion analysis localizes brain damage to left insula

He-autoscopy

[Heydrich and Blanke, Brain 2012] Out-of-body experiences in normal folks Example: «I was asleep on a settee with my wife. I was aware at one stage that I was out of my own body poised six feet or so above and peering down at the two of us laying on the settee.» [Green, Out-of- the-body experiences, 1968]..

“One day, at age 17, I was walking alone at night during a snowstorm in a singularly quiet place. I noticed that the ground looked further away than usual, and then it seems that I was looking down from a height of perhaps 10 meters, watching myself crossing the field.” Marvin Minsky The many selves in Cognitive Neuroscience

•Visual Recognition: Recognizing one's image in a mirror

•Memory: Autobiographical memory

•Thought: “Cogito ergo sum”, Ability to think “I” thoughts; ability to think of oneself as oneself, have a self concept

•Language: first-person and self-reflexive pronouns

•Intentions/

•Social: ability to adapt the perspective of the other to oneself; capacity to discriminate self from other Bodily Self-consciousness (relevance for philosophy)

Self-location (Where am I localized ?)

First-person perspective (Where do I perceive from?)

Self-identification (What do I experience as my body?)

[Blanke & Metzinger, TiCS 2009]