Impaired Mirror-Image Imitation in Asperger and High-Functioning Autistic Subjects

Abstract

Imitation is crucial for proper development of social and communicative skills. Here, we argue that, based on an error analysis of a behavioral imitation task, adult Asperger and high-functioning autistic subjects suffer from an intriguing deficit of imitation: they lack the natural preference for imitation in a mirror-image fashion. The imitation task consisted of a simple movement sequence of putting a pen with the left or right hand into a green or a blue cup using one of two possible grips. The subjects were asked to imitate the experimenter's hand movements either using the crossed hand (e.g., the subject's right hand corresponding to the experimenter's right hand) for imitation or to imitate as if looking in a mirror (e.g., the subject's left hand corresponding to the experimenter's right hand). When people normally view other persons face-to-face, they prefer to imitate as in a mirror, and observation of mirror-image-like movements speeds up performance in nonimitative tasks. However, our autistic subjects, defective in social cognition, did not profit from mirror-image movements of others. These results provide a new insight into the difficulties that autistic subjects face in viewing and understanding actions of others.

EEG mu rhythm and imitation impairments in individuals with autism spectrum disorder

“…While there have been numerous studies examining imitation skills in autism, the vast majority of these studies have been conducted with children. Two studies conducted with teens found continued evidence of imitation impairments (Rogers et al, 1996;Loveland et al, 1994) and one other study of adults with ASD found significantly more errors and no benefits in using a mirror image to enhance performance (Avikainen et al, 2003). The current study found continued impairments in single and multiple step acts that involved both hand and face imitation, imitative acts that required both hands, and actions that involved meaningless movements.…”

“…School age children with autism also show imitation deficits (Hammes & Langdell, 1981;Ohta, 1987, Smith & Bryson, 1998Green et al, 2002;Jones & Prior, 1985). Such impairments persist into adolescence and adulthood although there are fewer studies that have examined this age group (Rogers et al, 1996;Avikainen et al, 2003;Hobson & Lee, 1999). Hobson and Lee (1999) found that teens with autism were able to imitate goal directed actions but failed to imitate the style in which the examiner performed the task with greater frequency than the control group.…”

“…Further, during the imitative acts, the subjects with autism made considerable reversal errors, errors in which the imitator replicates the gestures but in the perspective of how the gesture was observed. Similarly, Avikainen et al (2003) examined imitation in adults through a task in which participants imitated the experimenter's actions using either the same hand or opposite hand. They found that while typical adults used the mirror image of the experimenter's actions to increase response speed and accuracy, the individuals with Asperger syndrome and high functioning autism failed to capitalize on the mirror image.…”

Movements, actions and tool-use actions: an ideomotor approach to imitation

“…chose the wrong cup) than effector errors (i.e. chose the wrong hand) and fewer effector errors than grip errors (Wohlschläger & Bekkering 2002b;Avikainen et al 2003). This pattern of results has often been taken as evidence for a hierarchical decomposition of the perceived act in imitation (cf.…”

Understanding the mechanisms behind deficits in imitation: Do individuals with autism know ‘what’ to imitate and do they know ‘how’ to imitate?

“…Such errors imply that a person holds up the palm of his hand facing towards himself when he has observed the demonstrator facing his palm of the hand towards the other person. A number of studies reported reversal errors in imitation of actions without objects (Beadle-Brown, 2004;Dewey, Cantell, & Crawford, 2007;Ohta, 1987, Smith & Bryson, 1998Whiten & Brown, 1998) and actions with objects (Avikainen, Wohlschlager, Liuhanen, Hanninen, & Hari, 2003;Hobson & Lee, 1999;Meyer & Hobson, 2004) in children and adolescents with autism in contrast to non-autistic controls. Compared to appropriate controls, they were significantly less likely to imitate the orientation of an action in relation to the demonstrator's body.…”