Time course analyses confirm independence of automatic imitation and spatial compatibility effects

Automatic imitation has been used as a behavioural index of the functioning of the human mirror system (e.g. Brass, Bekkering, Wohlschlager, & Prinz, 2000; Heyes, Bird, Johnson, & Haggard, 2005; Kilner, Paulignan, & Blakemore, 2003). However, several papers have criticised the assumption that automatic imitation is mediated by the mirror system on the grounds that automatic imitation has been confounded with simple spatial compatibility (Aicken, Wilson, Williams, & Mon-Williams, 2007; Bertenthal, Longo, and Kosobud, 2006; Jansson, Wilson, Williams, & Mon-Williams, 2007). Two experiments are reported in which, in contrast with previous studies, automatic imitation was measured on both spatially compatible and spatially incompatible trials, and automatic imitation was shown to be present regardless of spatial compatibility. Additional features of the two experiments allowed measurement of the time courses of the automatic imitation and spatial compatibility effects both within and across trials. It was found that automatic imitation effects follow a different time course from spatial compatibility effects, providing further evidence for their independence and supporting the use of automatic imitation as a behavioural marker of mirror system functioning

From heart to mind: linking interoception, emotion, and theory of mind

Theory of Mind (ToM) is traditionally characterized as the ability to represent mental states. Such a characterization leaves little room for studying individual differences in ToM – individuals either can, or cannot, represent mental states – and this binary classification cannot quantify the subtle individual differences observed in typical and atypical populations. In recognition of this problem, attempts have been made to provide a more detailed characterization of the constituent psychological processes which support the representation of mental states (Happé et al., 2017, Schaafsma et al., 2015), and the neurocomputational principles underpinning ToM (Koster-Hale & Saxe, 2013), in order to identify the source of individual differences. A recent model is of interest as it forwards the novel argument that interoception, perception of the internal state of the body, is a fundamental component of ToM (Ondobaka, Kilner, & Friston, 2017). Here we report the first test of the link between interoception and ToM

Embodiment in the Enfacement Illusion is mediated by self-other overlap

The enfacement illusion is a facial version of the rubber hand illusion, in which participants experience tactile stimulation of their own face synchronously with observation of the same stimulation applied to another’s face. In previous studies, participants have reported experiencing illusory embodiment of the other’s face following synchronous compared to asynchronous stimulation. In a series of three studies, we addressed three questions: a) how does similarity between the self and the other, operationalised here as being of the same or different gender to the other, impact the experience of embodiment in the enfacement illusion; b) does the experience of embodiment result from alterations to the self-concept; and c) is susceptibility to the experience of embodiment associated with interoceptive processing, i.e., perception of the internal state of the body? Results indicate that embodiment is facilitated by similarity between the self and the other and is mediated by the incorporation of the other into the self-concept; but sensitivity to one’s own internal states does not impact upon embodiment within the enfacement illusion

What happened to mirror neurons?

Ten years ago, Perspectives in Psychological Science published the Mirror Neuron Forum, debating the role of mirror neurons in action understanding, speech, imitation and autism, and asking whether mirror neurons are acquired through visual-motor learning. Subsequent research on these themes has made significant advances, which should encourage further, more systematic research: Action understanding - Multivoxel pattern analysis, patient studies, and brain stimulation suggest that mirror neuron brain areas contribute to low-level processing of observed actions (e.g. distinguishing types of grip), but not to high-level action interpretation (e.g. inferring actors’ intentions). Speech perception – Although it remains unclear whether mirror neurons play a specific, causal role in speech perception, there is compelling evidence for the involvement of the motor system in the discrimination of speech in perceptually noisy conditions. Imitation – There is strong evidence from patient, brain stimulation and brain imaging studies that mirror neuron brain areas play a causal role in copying of body movement topography. Autism – Studies using behavioural and neurological measures have tried and failed to find evidence supporting the “broken mirror” theory of autism. Furthermore, research on the origin of mirror neurons has confirmed the importance of domain-general visual-motor associative learning, rather than canalised visual-motor learning, or motor learning alone

The role of the right temporoparietal junction in the control of imitation

Controlling neural representations of the self and other people is fundamental to social cognition. Brain imaging studies have implicated the right temporoparietal junction (rTPJ) in this ability, but causal evidence for its role is lacking. A debate is also ongoing regarding whether the control of, or switching between, self and other representations is a specialized or domain-general process: the rTPJ's well-established role in reorienting attention supports a domain-general process, but a role specific to social cognition has also been proposed. Neuronavigated repetitive transcranial magnetic stimulation was used to target the rTPJ (and a control mid-occipital site) during a task requiring participants to switch between representations of others' actions on both a social and a nonsocial level, by manipulating imitative and spatial compatibility simultaneously and independently. Both imitative and spatial compatibility effects were apparent on response times; however, the effect of imitative compatibility was significantly stronger, indicating less control of imitation, during stimulation of the rTPJ relative to the control site. This suggests that the rTPJ is involved in switching between self and other representations, and further, that this process may not be entirely domain general.</p

A task control theory of mirror-touch synesthesia

Ward and Banissy's illuminating discussion of mirror-touch synesthesia (MTS) encourages research testing two alternatives to Threshold Theory: Their own Self-Other Theory, and "Task Control Theory". MTS may be due to abnormal mirror activity plus a domain-general, rather than a specifically social, impairment in the ability to privilege processing of task-relevant over task-irrelevant information.</p

Modulation of cortical motor outputs by the symbolic meaning of visual stimuli.

Abstract The observation of an action modulates motor cortical outputs in specific ways, in part through mediation of the mirror neuron system. Sometimes we infer a meaning to an observed action based on integration of the actual percept with memories. Here, we conducted a series of experiments in healthy adults to investigate whether such inferred meanings can also modulate motor cortical outputs in specific ways. We show that brief observation of a neutral stimulus mimicking a hand does not significantly modulate motor cortical excitability (Study 1) although, after prolonged exposure, it can lead to a relatively nonspecific modulation (Study 2). However, when such a neutral stimulus is preceded by exposure to a hand stimulus, the latter appears to serve as a prime, perhaps enabling meaning to the neutral stimulus, which then modulates motor cortical excitability in accordance with mirror neuron-driving properties (Studies 2 and 3). Overall results suggest that a symbolic value ascribed to an otherwise neutral stimulus can modulate motor cortical outputs, revealing the influence of top-down inputs on the mirror neuron system. These findings indicate a novel aspect of the human mirror neuron system: an otherwise neutral stimulus can acquire specific mirror neuron-driving properties in the absence of a direct association between motor practice and perception. This significant malleability in the way that the mirror neuron system can code otherwise meaningless (i.e. arbitrarily associated) stimuli may contribute to coding communicative signals such as language. This may represent a mirror neuron system feature that is unique to humans

Poorer representation of minds underpins less accurate mental state inference for out-groups

Societies are becoming more polarised, driven in part by misconceptions about out-groups’ beliefs. To understand these effects, one must examine the cognitive processes underlying how people think about others. Here, we investigate whether people are less prone to theorise about the minds of out-groups, or less able to do so. Participants (Study 1: n = 128; Study 2: n = 128) made inferences about social and political beliefs held by real in-group and out-group members, and could choose to receive further information to improve these inferences. Results show: (1) participants sought equivalent or greater information about out-groups relative to in-groups; but despite this, (2) made significantly less accurate inferences for out-groups; and (3) were significantly less aware of their reduced ability. This shows that poorer mental state inference is not underpinned by a reduced propensity to consider out-group minds, but instead by a worse representation of the minds of out-groups

The Theory of Mind Hypothesis of Autism: A Critical Evaluation of the Status Quo

The theory of mind (ToM) hypothesis of autism is the idea that difficulties inferring the mental states of others may explain social communication difficulties in autism. In the present article, we critically evaluate existing theoretical accounts, concluding that none provides a sufficient explanation of ToM in autism. We then evaluate existing tests of ToM, identifying problems that limit the validity of the conclusions that may be drawn from them. Finally, as an example of how the identified issues may be resolved, we describe work developing a psychological account of ToM (the Mind-space framework) and a new test of ToM accuracy (the Interview Task)

Mirror Neurons from Associative Learning

Mirror neurons fire both when executing actions and observing others perform similar actions. Their sensorimotor matching properties have generally been considered a genetic adaptation for social cognition; however, in the present chapter we argue that the evidence in favor of this account is not compelling. Instead we present evidence supporting an alternative account: that mirror neurons’ matching properties arise from associative learning during individual development. Notably, this process was not ‘designed’ by genetic evolution specifically to produce mirror neurons, but just happens to produce them when the developing system receives correlated experience of observing and executing similar actions. Sensorimotor experience with non-matching actions, or with objects and actions, is hypothesized to generate other cell types in the same regions through the same process. The associative account has major implications for research into mirror neuron function and suggests several important lines of future research