Imitation is an early social communication skill defined as copying observed behaviors. Imitation skills are classified both according to the body part where the imitated action takes place and according to the time the imitated action takes place. In the literature, there are three types of imitation skills, namely object imitation, motor imitation and vocal imitation, depending on the body part where the action takes place. While object imitation involves imitation of actions performed with objects, motor imitation is a type of imitation that includes imitation of non-object body movements, large-small muscle motor actions and gestures. separated oral motor imitations from motor imitations and treated them as a separate type of imitation. Oral motor mimics involve imitation of facial actions related to the oral region (eg, sticking out tongue and moving it to either side of the mouth, making a kissing gesture). Sound imitations, on the other hand, consist of imitations of meaningful and non-meaningful words and sounds. There are three types of imitation skills, namely, immediate imitation skills, delayed imitation skills, and deferred imitation skills, according to the time the imitated action takes place. While instant imitation skills are defined as performing the same action performed by the observed individual simultaneously with the observed individual; Delayed imitation skills are defined as the repetition of the observed action shortly after the modeled person. In delayed imitation skills, on the other hand, it is the case that the child does the same action that he observed before, without being a model again after a long time.
It is accepted that babies’ acquisition of imitation skills is an important developmental step from both social and cognitive perspectives. emphasized that there is a relationship between imitation and social interactions, and stated that imitation serves two functions: understanding complex observations and mutual social communication during infancy. Therefore, imitation is used for learning and social communication in infancy. In addition to being an important tool for babies to learn new behaviors, imitation continues to function as a tool for learning throughout life. Imitations for social communication are one of the basic building blocks of purposeful communication in children with normal development and developmental delay.
In normally developing children, imitation occurs early in infancy. Babies are born with a primitive representational competence in imitating facial-mouth movements. Babies 1-4. repeats their own behavior imitated by someone else in months 4-8. They repeat the behaviors they spontaneously produced before between months. With the onset of purposeful communication, they begin to understand that other individuals are purposeful beings. At 12 months, they use this information to decide what the person doing an action is trying to do in the context of imitation and decide which element of the observed action to imitate. Delayed imitation skills begin to be acquired at an average of 18 months.
One of the nonverbal social communication disorders seen in children with ASD is experienced in the development of imitation. There are many studies in the literature showing that children with ASD experience limitations in their imitation skills compared to their normally developing peers, and that their imitation performance is significantly lower than children with different developmental delays. The fact that the imitation skills of children with ASD are limited compared to both children with normal development and developmental delay, shows that the limitation in imitation skills is one of the prominent features of ASD. Charman et al. (1997) compared the imitation skills of 20-month-old children with ASD, children with developmental delay, and children with normal development; They found that when nonverbal mental age was controlled for, children with ASD showed significantly lower imitation performance than children with both normally developing and developmental delays. Dawson et al. (1998) matched children with ASD, Down syndrome and normal development according to their receptive language intelligence age and communication scores, and children with Down syndrome and ASD according to their chronological age and examined whether there was any difference in imitation behaviors between groups. As a result of the study, they found that children with ASD performed lower than other groups in both immediate imitation and delayed imitation. Both Charman et al. (1997) and Dawson et al. (1998) performed an action with an object in a structured environment while evaluating imitation skills in their research and presented the object to the child for later imitation.
Children with ASD also show limitations in their imitation skills when compared with children with developmental delays. Rogers et al. (2003) compared the imitation development of 26-41 month-old children with ASD with those with normal development, developmental delay (children with Down syndrome, chromosomal disorders and developmental delay) and Fragile X syndrome. They found that their scores were significantly lower than all groups. Stone, Ousley, and Littleford (1997), on the other hand, conducted a study comparing the imitation skills of children with ASD aged 26-36 months with normally developing children matched for their intellectual age, and with children with developmental delay, whose mental age was matched according to chronological age and expressive language score. The researchers, who claimed that children with ASD showed significantly lower performance in imitation than children with developmental delays, claimed that the limitations seen in imitation were an autism-specific disorder. In the studies of Rogers et al. (2003), Stone, Ousley, and Littleford (1997), and Turan and Ökcün-Akçamuş (2013), structured imitation processes were used, and in these studies objective imitation skills, motor imitation skills, and oral motor imitation skills were evaluated. As a result of these studies, it was found that children with ASD showed limitations in all areas of imitation. Stone, Ousley, and Littleford (1997) found that children had more difficulties in motor imitation skills than object imitation skills and meaningless object imitations such as walking the toy comb on the table than the meaningful object imitations such as walking the toy dog on the table. When the limitations in imitation skills were analyzed according to imitation types, it was seen that children with ASD scored higher in object imitation skills than motor imitations, and they had more difficulty in meaningless object imitations compared to meaningful object imitations.
Children with ASD show lower performance in spontaneous imitation skills than in structured imitation skills. Ingersoll (2008b) conducted a study comparing the structured imitation skills in a structured environment with the spontaneous imitation skills in a natural environment of normally developing children and children with ASD matched for nonverbal intelligence age. As a result of the study, it was found that children with ASD performed lower than normally developing children in both types of imitation. When the performances of children with ASD were examined according to imitation types, it was found that they had more difficulties in spontaneous imitation skills, on the contrary, children with normal development showed similar performance in both types of imitation. Structured imitation and spontaneous imitation require different competencies. With structured imitation processes, the child reproduces the observed action without a personal purpose. In cases where the imitation is done and revealed by the child’s own will, the child chooses one of all the behavior patterns in his/her environment that matches his/her motivation. The fact that children with ASD have more difficulty in spontaneous imitation skills than structured imitation skills supports Quill’s (2002) comment that children with ASD only imitate the action and have limitations in understanding the content of the action. Rogers and Pennington (1991) argue that imitation constitutes an early social competence of sharing emotions and theory of mind. While deciding what and how to imitate for communicative purposes, infants make choices by understanding the purpose and intention of the individuals they observe in context and by interpreting the behavior. Normally developing babies do not simply reproduce the behavior they observe or the results of the behavior, they see the behavior of the observed individual as purposeful and in this process, they choose the behavior they will repeat, adapt and adapt their own behavior. They can distinguish the non-purposeful behaviors of the observed individual while modeling and reveal new behaviors towards the same result, or they can emerge by imitating the process of an incomplete, unobserved behavior. All these behaviors take place in the context of joint attention.
As a result, studies show that children with ASD show lower performance in imitation skills than children with both normal development and developmental delay, and that the difficulties experienced by children with ASD in spontaneous imitation skills increase. Imitation skills are one of the early social communication skills and are considered as a communicative action as well as a necessary skill for social learning. The fact that imitation is an early social communication skill and its relationship with language development shows that the limitations experienced in imitation skills in children with ASD are important for language development. It is thought that imitation problems seen in children with ASD are one of the main obstacles in establishing social relationships and in the learning process within these social relationships.