Comparing the ability of motor simulation in children with cerebral palsy and typical children: The role of embodied cognition

In cognitive linguistics, researchers argue that but the entire cognitive system influences language structure, not just specific brain areas. Embodied Construction Grammar (ECG) connects language to the sensory-motor system and human conceptual experiences. Grounded-embodied theories suggest that bodily interactions with the physical and social environment shape language and thought. In this context, motor simulation is crucial for understanding language. Research shows that comprehending language activates the motor and pre-motor cortex, specifically in response to motor language involving specific body parts like the hands, feet, and mouth. Motor experiences are highly significant from infancy. Children continually develop their motor foundations during this period through various learning processes. Children’s growth and development begin with these basic movements. Motor experiences, such as interacting with the physical environment and objects and communicating with parents, are the main foundations of cognitive-motor development, which can lead to the perception and even conceptualization of movement.However, a key unresolved debate is how motor impairment in children with Cerebral Palsy (CP) affects motor cortex involvement while processing action verbs. This study, the first of its kind, investigates this issue to inform diagnostic and therapeutic interventions for children with CP.

This descriptive-analytical case-control study involved two groups of Persian-speaking children aged 7 to 12. The first group consisted of 13 children with CP (6 boys, 7 girls; mean age=9.38±1.50), recruited from special schools for children with developmental disabilities. Special schools or classes are provided for children with special educational needs for special consideration and support, following the mainstream curriculum in normal education settings. The second group, comprising 13 Typically Developing (TD) children (6 boys, 7 girls; mean age=9.38±1.45), was selected from public schools. Both groups were matched for age, gender, socio-economic status, and grade level.The CP group excluded children with neuropsychiatric comorbidities, intellectual disabilities, or metabolic, genetic, and epileptic disorders. All participants had normal or corrected-to-normal vision and hearing, and their developmental quotient/IQ fell within normal limits. They could use the keys on a computer keyboard. These factors were obtained according to school documentation of general health care screening programs regarding the outcomes of interviews with parents of children and examination of children by an experienced child psychologist, an optometrist, and an audiologist. Regarding a standard scale of mobility and manual function, 54% of children were classified at level III (walks with a power wheelchair), and 46% of children were classified at level II (walks with a walker). Lack of parental consent, scheduling problems, and non-compliance with inclusion criteria prevented their enrollment.The experimental task involved 12 black-and-white stick-figure images representing action verbs related to body parts (hands and feet). Each image was paired with three types of Persian verbs: (1) a matching verb, (2) a same-effector mismatch verb (using the same body part but unrelated to the image), and (3) a different-effector mismatch verb (using a different body part). In order to use images that appropriately describe specific motor actions, facial details were intentionally removed. As a result, 36 verb-image pairs were presented to participants.

Descriptive statistics categorized the data based group (CP vs. TD) and verb type (matching, same-effector mismatch, different-effector mismatch). The Kolmogorov-Smirnov test confirmed the normality of data distribution. A one-way ANOVA was conducted to explore inter-variable relationships, with a significance threshold of P<0.05.Of the 26 participants, 13 were assigned to the case group, and the remaining 13 formed the control group. Overall, 12 boys (46.15%) and 14 girls (53.84%) enrolled in the study. Without considering the type of verb in the CP group, the minimum reaction time was 2.14 seconds, and in the control group, it was 1.04 seconds. The percentage of non-response in the control and CP groups was 0.4% and 1.5%, respectively.A significant difference was found between the two groups in all verb types. CP participants had slower Reaction Times (RTs) across the board, including Matching verbs [CP Mean=4.36, TD Mean=3.06 (P<0.001)], Same-effector mismatches [CP Mean=4.12, TD Mean=3.23 (P<0.001)], and Different-effector mismatches [CP mean=4.26, TD mean=3.41 (P<0.001)].Additionally, TD children outperformed CP children in the frequency of correct responses across all verb types, including Matching verbs (CP=60.3%, TD=80.8%), Same-effector mismatches (CP=59.6%, TD=64.1%), and Different-effector mismatches (CP=67.9%, TD=76.3%).Repeated measures ANOVA followed by Bonferroni post-hoc tests indicated no significant effect of verb types on RTs in the CP group. However, significant differences were observed between matching and different-effector non-matching conditions in the TD group.

This study aimed to ascertain how embodied cognition plays an essential role in understanding language related to action verbs among children with CP. Currently, a wealth of evidence indicates that sensory and motor grounding is essential for action-language comprehension, but little is known about their potential contributions to processing motor simulation in children with CP. Predominantly, the present investigation intended to identify how the motor simulation of the CP groups differ from those of TD peers and address any significant differences in reaction time across conditions in each group.The present study highlights the role of embodied cognition in understanding action verbs, particularly in children with CP. Sensory-motor grounding is essential for action-language comprehension, but children with CP show distinct differences in motor simulation compared to their TD peers. These findings add to the growing number of studies highlighting the complex nature of verb impairments in specific populations Because of the interaction between sensorimotor cortex activation and psychological factors, they suggest that cognition is inseparable from the body and is shaped by sensory-motor experiences. Early identification of linguistic processing deficits in sensory-motor systems can aid in better memory representation and understanding related words, specifically in Persian-speaking children with CP.Beyond, their theoretical significance, the present findings have practical implications for CP children. Recognizing information about how these patients perceive movement, has implications for choosing timely and tailored interventions, therapeutic approaches, and individualized education plans.