Hearing one’s own name increases functional connection strength between areas of the Human Mirror Neuron System

Abstract

Responding to one’s own name is a fundamental social function. Previous investigations demonstrated that there is a distinct brain electrical response to hearing one’s own name (Holeckova et al., 2006). The fMRI literature suggests that a specific network of areas is involved in processing social information about other people’s intentions, including other people calling one’s own name.This network includes the medial prefrontal, parietal and middle temporal cortical regions, and is called the Mirror Neuron System because it contains neurons that are active both when individuals perform actions and when they see another person performing actions (Kampe et al., 2003). The present study investigates the response to hearing one’s own name using high-density EEG recording. Event-related spectral perturbation (ERSP) analysis was used to investigate the time course and topography of the response. Additionally, the high-density recording allows reconstruction of the cortical generators of the electrical signals measured on the surface of the scalp through standard generative head models (Michel et al., 2004). We reconstructed the time series of the electrical signal in cortical regions of interest (ROIs) of the human mirror neuron system. Linear coupling between these regions was compared between the own name and control name condition.

Full text

This study investigated the psychophysiology of the response to hearing
recordings of people signalling the intention to communicate by calling
the subject’s name. Event-related spectral perturbations analysis
indicates increased power in the alpha frequency band (8-12Hz)
between 200 and 300ms after stimulus onset over right temporal
channels. This is followed by an increase in activity over left frontal
channels between 600 and 800ms after stimulus onset. Increases in the
frequency band power indicate resetting of neural oscillators in response
to the stimulus. This is likely to be due to more processing resources
being devoted to the stimulus.!
Source reconstruction localises the generators of the scalp-measured
electrical activity to the right middle temporal and left frontal cortex.
These regions have been linked to processing social information as part
of the “social brain” (Kampe et al., 2003). Further, these regions are part
of the human mirror neuron system. The source reconstruction also
indicates that other regions are active when processing SON and CN. !
Correlations between the reconstructed time series of cortical regions of
interest that are part of the human mirror neuron system were calculated
to investigate if the human mirror neuron system is engaged when
processing hearing one’s own name (see Kampe et al., 2003). We find
that linear coupling is significantly increased during the SON compared
to CN condition.
Introduction
Discussion
Joe M. Bathelt, Chris A. Clark, Naomi J. Dale, Michelle de Haan!
Developmental Cognitive Neuroscience Unit, UCL Institute of Child Health
Hearing one’s own name increases functional connection strength between areas
of the Human Mirror Neuron System
Materials & Methods
Results
Conclusion
Participant Sample!
The sample consisted of 20 adult volunteers (8 female, age: 29.53 ± 4.01 SD)
recruited from UCL and the Institute of Child Health.).!
!
EEG Recording!
EEG was measured with a 128-channel EGI Geodesic Sensor Net and
NetAmps 200 amplifier (Electrical Geodesics Inc., OR). !
!
Stimuli!
Participants were presented with recordings of four native English speakers (2
female) saying either “Hey, [name of participant]!” or “Hey, [control name]!”.
Control names consisted of the same number of syllables as the participant’s
name, but started with a different phoneme, e.g. “Hey, Thomas” and “Hey,
Martin”. The presentation of stimuli was randomised. A total of 80 stimuli was
presented. The duration of the experiment was 8 minutes.!
!
Source Reconstruction!
The likely generators of electrical activity measured on the scalp surface were
reconstructed using a Boundary Element Model based on the Montreal
Neurological Institute standard head. Brain activity was reconstructed from the
generative model through Minimum Norm Estimatation (MNE). !
Cortical regions of interest (ROIs) were identified on the MNI cortex through
FreeSurfer cortical parcellation according to the Desikan-Killany atlas. The time
series of cortical ROIs were calculated using BrainStorm algorithms.
Responding to one’s own name is a fundamental social function.
Previous investigations demonstrated that there is a distinct brain
electrical response to hearing one’s own name (Holeckova et al., 2006).
The fMRI literature suggests that a specific network of areas is involved
in processing social information about other people’s intentions,
including other people calling one’s own name.This network includes
the medial prefrontal, parietal and middle temporal cortical regions, and
is called the Mirror Neuron System because it contains neurons that are
active both when individuals perform actions and when they see
another person performing actions (Kampe et al., 2003).!
The present study investigates the response to hearing one’s own name
using high-density EEG recording. Event-related spectral perturbation
(ERSP) analysis was used to investigate the time course and
topography of the response. Additionally, the high-density recording
allows reconstruction of the cortical generators of the electrical signals
measured on the surface of the scalp through standard generative head
models (Michel et al., 2004). We reconstructed the time series of the
electrical signal in cortical regions of interest (ROIs) of the human mirror
neuron system. Linear coupling between these regions was compared
between the own name and control name condition.
I
Event-related spectral perturbations (ERSP)
II Cortical source reconstruction
Mirror neuron system connectivity
III
•event-related spectral perturbations:!
•the response to hearing one’s own name is characterised by an
early activation over right temporal and a later activation over left
frontal channels. SON is processed preferentially in both early
stages of cortical processing in the temporal lobe and later
cognitive stages in the frontal lobe!
•source analysis:!
•source reconstruction localises the early response to the right
middle temporal cortex and the late response to the left
prefrontal cortex !
•cortical region of interest connectivity:!
•the linear coupling between cortical regions of the human mirror
neuron system is increased in the subject’s own name condition
compared to the control name condition!
→ this is indicative of enhanced engagement of the mirror
neuron !
system when hearing one’s own name
References
Kampe, Knut K W, Chris D Frith, and Uta Frith (2003): “‘Hey John’: Signals
Conveying Communicative Intention Toward the Self Activate Brain Regions
Associated with ‘Mentalizing,’ Regardless of Modality.” Journal of Neuroscience
23, no. 12: 5258–63. !
Holeckova, Irena, Catherine Fischer, Marie-Hélène Giard, Claude
Delpuech, and Dominique Morlet (2006): “Brain Responses to a
Subject’s Own Name Uttered by a Familiar Voice.” Brain Research 1082,
no.1: 142–152!
Michel, Christoph M, Micah M Murray, Göran Lantz, Sara Gonzalez,
Laurent Spinelli, and Rolando Grave de Peralta (2004): “EEG Source
Imaging.” Clinical Neurophysiology : Official Journal of the International
Federation of Clinical Neurophysiology 115, no. 10: 2195–222. !
Source activity 200ms after stimulus onset:
Subject’s own name
Control name
Source activity 600ms after stimulus onset:
Subject’s own name
Control name
The source reconstruction shows early temporal and later
frontal activation in line with the results of the ERSP analysis.
Further, other cortical areas that were not statistically
different in the ERSP contrast of the condition show
activations. These areas include regions of the parietal
cortex.!
Activations are given in picoAmpère. The grey dots display
the position of the EEG sensors. The sources were
reconstructed through standard boundary element models
with minimum norm estimation.
The top row shows the correlation between the time series of all cortical regions of interest in the
subject’s own name condition on the left and the control name condition on the right. The bottom
left panel shows the p-value of the paired sample t-test between the correlation strength of all
connection between the ROIs. The bottom right panel shows the effect size of the t-test expressed
as values of r. The statistical comparison shows that the linear coupling between regions of the
mirror neuron system is stronger in the own name condition compared the control name condition.!
Subject’s own name Control name
p-values effect size
Event-related spectral perturbations were estimated through Morlet wavelet
decomposition. Statistical parametric mapping shows significant differences between the
subject’s own name and the controls name condition in the alpha frequency range
between 200 and 300ms post stimulus onset over temporal channels and between 600
and 800ms over frontal channels. Please note that edge effects in higher frequencies are
artefacts of the Morlet decomposition, which is optimised for lower frequency bands.!
The right panel shows the topography of the response in transverse glass brain view.!
!
Subject’s own name Control name
left frontal
right temporal
Abstract
right right
right left leftright
Subject’s own name !
vs Control name
• calling someone’s name signals the intention to communicate!
• this activates areas of the mirror neuron system, but the timing of their
activation is not known!
• using high-density EEG recording, this poster describes:!
i. the time course and topography of brain activity in response to
hearing one’s own name compared to a control name!
ii. the cortical generators of the electrical activity!
iii. the network interaction between regions that are thought to play a
role in mediating the response to one’s own name !
!
posterior
anterior
left
right
This research was founded by UCL Impact & Great Ormond Street Hospital Children’s Charity
Subject’s own name !
vs Control name