Morpho-Syntactic Deficit in Children with Cochlear Implant: Consequence of Hearing Loss or Concomitant Impairment to the Language System?

BACKGROUND: Among implanted children with similar duration of auditory deprivation and clinical history, the morpho-syntactic skills remain highly variable, suggesting that other fundamental factors may determine the linguistic outcomes of these children, beyond their auditory recovery. The present study analyzed the morpho-syntactic discrepancies among three children with cochlear implant (CI), with the aim of understanding if morpho-syntactic deficits may be characterized as a domain-specific language disorder. METHOD: The three children (mean age = 7.2; SD = 0.4) received their CI at 2.7, 3.7, and 5.9 years of age. Their morpho-syntactic skills were evaluated in both comprehension and production and compared with 15 age-matched normal-hearing children (mean age = 6.6; SD = 0.3). RESULTS: Cases 1 and 2 displayed a marked impairment across morphology and syntax, whereas Case 3, the late-implanted child, showed a morpho-syntactic profile well within the normal boundaries. A qualitative analysis showed, in Cases 1 and 2, language deficits similar to those of normal hearing children with Developmental Language Disorder (DLD). CONCLUSIONS: We suggest that a severe grammatical deficit may be, in some implanted children, the final outcome of a concomitant impairment to the language system. Clinical implications for assessment and intervention are discussed.

Sex Differences in Affective Facial Reactions Are Present in Childhood.

Adults exposed to affective facial displays produce specific rapid facial reactions (RFRs) which are of lower intensity in males compared to females. We investigated such sex difference in a population of 60 primary school children (30 F; 30 M), aged 7-10 years. We recorded the surface electromyographic (EMG) signal from the corrugator supercilii and the zygomatici muscles, while children watched affective facial displays. Results showed the expected smiling RFR to smiling faces and the expected frowning RFR to sad faces. A systematic difference between male and female participants was observed, with boys showing less ample EMG responses than age-matched girls. We demonstrate that sex differences in the somatic component of affective motor patterns are present also in childhood.

A developmental study on children's capacity to ascribe goals and intentions to others.

The capacity to ascribe goals and intentions to others is a fundamental step in child cognitive development. The aim of the present study was to assess the age at which these capabilities are acquired in typically developing children. Two experiments were carried out. In the first experiment, 4 groups of children (age range = 3 years 2 months-7 years 11 months) were shown pictures representing hand-object interactions and asked what the individual was doing (what task) and why (why task). In the why task, observed handgrip could be either congruent with the most typical action performed with that object (e.g., to drink in the case of a mug) or corresponding to the act of putting away the object. In the second experiment, children saw pictures showing a handgrip either within a context suggesting the most typical use of the object or its being put away. Results showed that by 3-4 years, children are able to state the goal relatedness of an observed motor act (what understanding), whereas the ability to report the intention underlying it (why understanding) is a later and gradual acquisition, reaching a high performance by 6-7 years. These results, besides their intrinsic value, provide an important baseline for comparisons with studies on developmental disorders, also highlighting the relevance of distinguishing what and why understanding.

Motor representation of actions in children with autism.

BACKGROUND: Children with Autistic Spectrum Disorders (ASD) are frequently hampered by motor impairment, with difficulties ranging from imitation of actions to recognition of motor intentions. Such a widespread inefficiency of the motor system is likely to interfere on the ontogeny of both motor planning and understanding of the goals of actions, thus delivering its ultimate effects on the emergence of social cognition. METHODOLOGY/PRINCIPAL FINDINGS: We investigate the organization of action representation in 15 high functioning ASD (mean age: 8.11) and in two control samples of typically developing (TD) children: the first one, from a primary school, was matched for chronological age (CA), the second one, from a kindergarten, comprised children of much younger age (CY). We used nine newly designed behavioural motor tasks, aiming at exploring three domains of motor cognition: 1) imitation of actions, 2) production of pantomimes, and 3) comprehension of pantomimes. The findings reveal that ASD children fare significantly worse than the two control samples in each of the inspected components of the motor representation of actions, be it the imitation of gestures, the self-planning of pantomimes, or the (verbal) comprehension of observed pantomimes. In the latter task, owing to its cognitive complexity, ASD children come close to the younger TD children's level of performance; yet they fare significantly worse with respect to their age-mate controls. Overall, ASD children reveal a profound damage to the mechanisms that control both production and pre-cognitive "comprehension" of the motor representation of actions. CONCLUSIONS/SIGNIFICANCE: Our findings suggest that many of the social cognitive impairments manifested by ASD individuals are likely rooted in their incapacity to assemble and directly grasp the intrinsic goal-related organization of motor behaviour. Such impairment of motor cognition might be partly due to an early damage of the Mirror Neuron Mechanism (MNM).

Hemimegalencephalic variant of epidermal nevus syndrome: case report and literature review.

The epidermal nevus syndrome (ENS) is an uncommon neurocutaneous disorder in which epidermal nevi are found in association with congenital abnormalities of the brain, eye, and/or skeleton. The association of epidermal nevi and neurologic abnormalities was comprehensively described by Schimmelpenning in 1957. Pavone et al. (1991) identified a homogeneous variant of ENS with hemimegalencephaly, gyral malformation, mental retardation, seizures and facial hemihypertrophy. A 13-year-old boy with the neurologic variant of ENS with hemimegalencephaly, facial asymmetry, febrile seizures and mental retardation is reported. Additionally, we performed a literature review using the search terms "epidermal nevus syndrome" and "hemimegalencephaly", including secondary sources of data such as reference lists of articles reviewed. We found 57 previously reported cases with the hemimegalencephalic variant of epidermal nevus syndrome, in which the most frequent associated features are severe epilepsy, in about half of cases with neonatal onset, mental retardation/developmental delay, ocular/visual involvement, and facial abnormalities.

Intention understanding in autism.

When we observe a motor act (e.g. grasping a cup) done by another individual, we extract, according to how the motor act is performed and its context, two types of information: the goal (grasping) and the intention underlying it (e.g. grasping for drinking). Here we examined whether children with autistic spectrum disorder (ASD) are able to understand these two aspects of motor acts. Two experiments were carried out. In the first, one group of high-functioning children with ASD and one of typically developing (TD) children were presented with pictures showing hand-object interactions and asked what the individual was doing and why. In half of the "why" trials the observed grip was congruent with the function of the object ("why-use" trials), in the other half it corresponded to the grip typically used to move that object ("why-place" trials). The results showed that children with ASD have no difficulties in reporting the goals of individual motor acts. In contrast they made several errors in the why task with all errors occurring in the "why-place" trials. In the second experiment the same two groups of children saw pictures showing a hand-grip congruent with the object use, but within a context suggesting either the use of the object or its placement into a container. Here children with ASD performed as TD children, correctly indicating the agent's intention. In conclusion, our data show that understanding others' intentions can occur in two ways: by relying on motor information derived from the hand-object interaction, and by using functional information derived from the object's standard use. Children with ASD have no deficit in the second type of understanding, while they have difficulties in understanding others' intentions when they have to rely exclusively on motor cues.

Planning actions in autism.

It has been suggested that the deficit in understanding others' intention in autism depends on a malfunctioning of the mirror system. This malfunction could be due either to a deficit of the basic mirror mechanism or to a disorganization of chained action organization on which the mirror understanding of others' intention is based. Here we tested this last hypothesis investigating the kinematics of intentional actions. Children with autism and typically developing children (TD) were asked to execute two actions consisting each of three motor acts: the first was identical in both actions while the last varied for its difficulty. The result showed that, unlike in TD children, in children with autism the kinematics of the first motor act was not modulated by the task difficulty. This finding strongly supports the notion that children with autism have a deficit in chaining motor acts into a global action.

Impairment of actions chains in autism and its possible role in intention understanding.

Experiments in monkeys demonstrated that many parietal and premotor neurons coding a specific motor act (e.g., grasping) show a markedly different activation when this act is part of actions that have different goals (e.g., grasping for eating vs. grasping for placing). Many of these "action-constrained" neurons have mirror properties firing selectively to the observation of the initial motor act of the actions to which they belong motorically. By activating a specific action chain from its very outset, this mechanism allows the observers to have an internal copy of the whole action before its execution, thus enabling them to understand directly the agent's intention. Using electromyographic recordings, we show that a similar chained organization exists in typically developing children, whereas it is impaired in children with autism. We propose that, as a consequence of this functional impairment, high-functioning autistic children may understand the intentions of others cognitively but lack the mechanism for understanding them experientially.