Sensory Effects of Action Observation
Evidence for Perceptual Enhancement Driven by Sensory Rather Than Motor Simulation
Abstract
Recent neurophysiological and behavioral studies suggest that the brain simulates the sensorimotor processing of observed actions. The relative contributions of sensory and motor simulation in this process remain unclear. Here, we use the well-established phenomenon of sensorimotor gating as a hallmark of motor representation. Perceived intensities of external stimuli are routinely suppressed during motor preparation and execution. Therefore, motor simulation should result in reduced perceptual intensity of sensory stimuli delivered during action observation. We obtained magnitude estimates for vibrotactile stimulation of the upper lip during observation of silent speech (lip-reading). Perceptual enhancement was consistently found across three experiments. The effect appeared to be specific to the observed action, somatotopically organized, and distinct from general attentional and response biases. We conclude that action observation produces perceptual enhancement. The experience of observing others’ actions may be driven more by sensory simulation than by motor simulation.
References
(2010). Force requirements of observed object lifting are encoded by the observer’s motor system: A TMS study. European Journal of Neuroscience, 31, 1144–1153.
(1982). Velocity-dependent suppression of cutaneous sensitivity during movement. Experimental Neurology, 77, 266–274.
(2007). Somatic and motor components of action simulation. Current Biology, 17, 2129–2135.
(2002). Modulated activation of the human SI and SII cortices during observation of hand actions. NeuroImage, 15, 491–500.
(2002). Lateralization in motor facilitation during action observation: A TMS study. Experimental Brain Research, 144, 127–131.
(2005). Somatosensory activations during the observation of touch and a case of vision-touch synaesthesia. Brain, 128, 1571–1583.
(2000). Why can’t you tickle yourself?. NeuroReport, 11, R11–R16.
(2002). Abnormalities in the awareness of action. Trends in Cognitive Neurosciences, 6, 237–242.
(2005). Inferring another’s expectation from action: The role of peripheral sensation. Nature Neuroscience, 8, 1295–1297.
(2001). Action observation activates premotor and parietal areas in a somatotopic manner: An fMRI study. European Journal of Neuroscience, 13, 400–404.
(2005). Action observation and acquired motor skills: An fMRI study with expert dancers. Cerebral Cortex, 15, 1243–1249.
(2012). Rapid enhancement of touch from non-informative vision of the hand. Neuropsychologia, 50, 1954–1960.
(1992). Mental movement simulation affects the N30 frontal component of the somatosensory evoked potential. Electroencephalography and Clinical Neurophysiology, 84, 284–292.
(2003). A ticklish question: does magnetic stimulation of the primary motor cortex give rise to an “efference copy”? Cortex, 39, 105–110.
(1987). Localization, timing and specificity of gating of somatosensory evoked potentials during active movement in man. Brain, 110, 451–467.
(1989). Delay in the execution of voluntary movement by electrical or magnetic brain stimulation in intact man: Evidence for the storage of motor programs in the brain. Brain, 112, 649–663.
(2002). A PET exploration of the neural mechanisms involved in reciprocal imitation. NeuroImage, 15, 265–272.
(2002). Speech listening specifically modulates the excitability of the tongue muscles: A TMS study. European Journal of Neuroscience, 15, 399–402.
(1995). Motor facilitation during action observation: A magnetic stimulation study. Journal of Neurophysiology, 73, 2608–2611.
(2007). G*Power 3: A flexible statistical power analysis program for the social, behavioral, and biomedical sciences. Behavior Research Methods, 39, 175–191.
(2001). The “shared-manifold” hypothesis – from mirror neurons to empathy. Journal of Consciousness Studies, 8, 33–50.
(1996). Action recognition in the premotor cortex. Brain, 119, 593–609.
(2003). Activations related to “mirror” and “canonical” neurones in the human brain: An fMRI study. NeuroImage, 18, 928–937.
(2004). Supplementary motor area provides an efferent signal for sensory suppression. Cognitive Brain Research, 19, 52–58.
(2004). Intersubject synchronisation of cortical activity during natural vision. Science, 303, 1634–1640.
(1993). Effects of jaw clenching, jaw movement and static jaw position on facial skin sensitivity to non-painful electrical stimulation in man. Archives of Oral Biology, 38, 303–308.
(2004). A touching sight: SII/PV activation during the observation and experience of touch. Neuron, 42, 335–346.
(1985). The motor theory of speech perception revised. Cognition, 21, 1–36.
(1983). Neural generators of N18 and P14 far field somatosensory evoked potentials studied in patients with lesions of thalamus or thalamo-cortical radiations. Electroencephalography and Clinical Neurophysiology, 56, 283–292.
(1998). Gating of somatosensory evoked potentials during voluntary movement of the lower limb in man. Experimental Brain Research, 120, 143–152.
(2005). Viewing speech modulates activity in the left SI mouth cortex. NeuroImage, 24, 731–737.
(1985). Visemes observed by hearing-impaired and normal hearing adult viewers. Journal of Speech and Hearing Research, 28, 381–393.
(2004). The mirror-neuron system. Annual Reviews in Neuroscience, 27, 169–192.
(1996). Localization of grasp representations in humans by PET: 1. Observation verses execution. Experimental Brain Research, 111, 246–252.
(2002). Somatosensory processing during movement observation in humans. Clinical Neurophysiology, 113, 16–24.
(2009). Effects of different viewing perspectives on somatosensory activations during observation of touch. Human Brain Mapping, 30, 2722–2730.
(2011). Effect of weight-related labels on corticospinal excitability during observation of grasping: A TMS study. Experimental Brain research, 211, 161–167.
(2008). Viewing a face (especially one’s own face) being touched enhances tactile perception on the face. Psychological Science, 19, 434–438.
(1999). Pre-movement gating of short-latency somatosensory evoked potentials. NeuroReport, 10, 2457–2460.
(2010). Crossmodal spatial attention. Annals of the New York Academy of Sciences, 1191, 182–200.
(2000). Cross-modal links between vision and touch in covert endogenous spatial attention. Journal of Experimental Psychology: Human Perception and Performance, 26, 1298–1319.
(2000). Modulation of cortical excitability during action observation: A transcranial magnetic stimulation study. NeuroReport, 11, 2289–2292.
(2001). Observation-execution matching system for speech: A magnetic stimulation study. NeuroReport, 12, 1341–1344.
(2006). Shared representations in body perception. Acta Psychologica, 121, 317–330.
(1998). Vision influences tactile perception without proprioceptive orienting. NeuroReport, 9, 1741–1744.
(2011). Modulation of the response to a somatosensory stimulation of the hand during the observation of manual actions. Experimental Brain Research, 208, 11–19.
(2006). Sensorimotor attenuation by central motor command signals in the absence of movement. Nature Neuroscience, 9, 26–27.
(2000). Time course and magnitude of movement-related gating of tactile detection in humans. II. Effects of stimulus intensity. Journal of Neurophysiology, 84, 863–875.
(2002). Time course and magnitude of movement-related gating of tactile detection in humans. III. Effect of motor tasks. Journal of Neurophysiology, 88, 1968–1979.
(1998). Time course and magnitude of movement-related gating of tactile detection in humans. I. Importance of stimulus location. Journal of Neurophysiology, 79, 947–963.
(2001). Motor prediction. Current Biology, 11, R729–R732.
