Adapted Picture Exchange Communication System using tangible symbols for young learners with significant multiple disabilities.

Practitioners need validated strategies for teaching children with significant multiple disabilities (e.g., cognitive, motor, and sensory disability) to use tangible symbols for expressive communication. This single-case experimental design study replicated the positive effect of an adapted protocol for teaching Phase 1 of the Picture Exchange Communication System (PECS) using tangible symbols and extended it to a younger group (4-7 years old) of learners with multiple disabilities. It also tested the effect of an adapted protocol for Phase 2 of PECS to incorporate use of a single switch speech-generating device to gain the attention of an adult communication partner. Two of three students who reached mastery in Phase 1 also reached mastery in Phase 2 and may have generalized requesting behavior from the interventionist (i.e., researchers) to their classroom teacher. Results add to the growing evidence base that shows that the adapted PECS Phase 1 procedures are a promising practice for learners with multiple disabilities, including sensory impairment, and provide preliminary evidence for a more efficient and effective approach to adapting PECS Phase 2 than previously studied for this group of learners. Directions for future research and recommendations for practice are provided.

Tapping-lips aggravated interictal bilateral discharges in EEG in the patients with Rett syndrome: a case report.

BACKGROUND: Rett syndrome (RTT) is a severe neurodevelopmental disorder mainly affecting females. One of the main clinical manifestations is hand stereotypies, which is presumed to based on dysfunction rather than on structural impairment. Reflex interictal discharge precipitated by tapping-lips in electroencephalogram (EEG) is a rare phenomenon among RTT. CASE PRESENTATION: We firstly reported a case of RTT concerning interictal reflex discharge precipitated by tapping- lips. The child, female, 5 years old, presented with a significant regression in motor development and language skills. She almost always tapped the lips with the right hand and stopped only when was interrupted. Her EEG results displayed extensive low amplitude fast wave could be elicited by lightly and slowly- rhythm tapping lips and multifocal bilateral discharges could be precipitated by relatively stronger and quicker rhythm action. It was when the movement stopped that corresponding discharges immediately disappeared. Besides, the reflex discharges were not precipitated by tapping- lips using observer's hand at the certain tempo and intensity. The hand stereotypies did not respond to antiepileptic drugs. CONCLUSIONS: Tapping- lips may be a somatosensory stimulation to precipitate interictal discharges in RTT, which may provide another idea to enrich the insight on hand stereotypies of RTT.

Further delineation of the MECP2 duplication syndrome phenotype in 59 French male patients, with a particular focus on morphological and neurological features.

The Xq28 duplication involving the MECP2 gene (MECP2 duplication) has been mainly described in male patients with severe developmental delay (DD) associated with spasticity, stereotypic movements and recurrent infections. Nevertheless, only a few series have been published. We aimed to better describe the phenotype of this condition, with a focus on morphological and neurological features. Through a national collaborative study, we report a large French series of 59 affected males with interstitial MECP2 duplication. Most of the patients (93%) shared similar facial features, which evolved with age (midface hypoplasia, narrow and prominent nasal bridge, thick lower lip, large prominent ears), thick hair, livedo of the limbs, tapered fingers, small feet and vasomotor troubles. Early hypotonia and global DD were constant, with 21% of patients unable to walk. In patients able to stand, lower limbs weakness and spasticity led to a singular standing habitus: flexion of the knees, broad-based stance with pseudo-ataxic gait. Scoliosis was frequent (53%), such as divergent strabismus (76%) and hypermetropia (54%), stereotypic movements (89%), without obvious social withdrawal and decreased pain sensitivity (78%). Most of the patients did not develop expressive language, 35% saying few words. Epilepsy was frequent (59%), with a mean onset around 7.4 years of age, and often (62%) drug-resistant. Other medical issues were frequent: constipation (78%), and recurrent infections (89%), mainly lung. We delineate the clinical phenotype of MECP2 duplication syndrome in a large series of 59 males. Pulmonary hypertension appeared as a cause of early death in these patients, advocating its screening early in life.

Autistic-like behaviour in Scn1a+/- mice and rescue by enhanced GABA-mediated neurotransmission.

Haploinsufficiency of the SCN1A gene encoding voltage-gated sodium channel Na(V)1.1 causes Dravet's syndrome, a childhood neuropsychiatric disorder including recurrent intractable seizures, cognitive deficit and autism-spectrum behaviours. The neural mechanisms responsible for cognitive deficit and autism-spectrum behaviours in Dravet's syndrome are poorly understood. Here we report that mice with Scn1a haploinsufficiency exhibit hyperactivity, stereotyped behaviours, social interaction deficits and impaired context-dependent spatial memory. Olfactory sensitivity is retained, but novel food odours and social odours are aversive to Scn1a(+/-) mice. GABAergic neurotransmission is specifically impaired by this mutation, and selective deletion of Na(V)1.1 channels in forebrain interneurons is sufficient to cause these behavioural and cognitive impairments. Remarkably, treatment with low-dose clonazepam, a positive allosteric modulator of GABA(A) receptors, completely rescued the abnormal social behaviours and deficits in fear memory in the mouse model of Dravet's syndrome, demonstrating that they are caused by impaired GABAergic neurotransmission and not by neuronal damage from recurrent seizures. These results demonstrate a critical role for Na(V)1.1 channels in neuropsychiatric functions and provide a potential therapeutic strategy for cognitive deficit and autism-spectrum behaviours in Dravet's syndrome.

Attenuated behaviour in Cornelia de Lange and fragile X syndromes.

BACKGROUND: Catatonia-like presentations in people with autism have been increasingly recognised within research and diagnostic guidelines. The recently developed Attenuated Behaviour Questionnaire has identified that attenuated behaviour [autistic catatonia] is very prevalent in people with autism spectrum disorders (ASDs) and associated with repetitive behaviour. In the current study, we investigated attenuated behaviour within two genetic syndromes associated with ASD and examined ASD and repetitive behaviour as longitudinal predictors of attenuated behaviour. METHOD: The Attenuated Behaviour Questionnaire was completed by parents/carers of 33 individuals with Cornelia de Lange syndrome (CdLS) and 69 with fragile X syndrome (FXS). Information collected from the same informants 4 years previously was utilised to examine ASD and repetitive behaviour as predictors of later attenuated behaviour, controlling for age, gender and ability. RESULTS: Catatonia-like attenuated behaviour was reported for individuals with CdLS (30.3%) and FXS (11.6%). Slowed movement was more prevalent in people with CdLS. No other phenotypic differences were observed. Across the two groups, repetitive behaviour predicted the presence of attenuated behaviour 4 years later, after controlling for age, gender and ability. CONCLUSIONS: Attenuated behaviour can be identified in individuals with CdLS and FXS and may have an effect on both adaptive behaviour and quality of life. Repetitive behaviours predicted subsequent risk within both groups and should be assessed by services as part of a pro-active strategy of support.

Prenatal ß-catenin/Brn2/Tbr2 transcriptional cascade regulates adult social and stereotypic behaviors.

Social interaction is a fundamental behavior in all animal species, but the developmental timing of the social neural circuit formation and the cellular and molecular mechanisms governing its formation are poorly understood. We generated a mouse model with mutations in two Disheveled genes, Dvl1 and Dvl3, that displays adult social and repetitive behavioral abnormalities associated with transient embryonic brain enlargement during deep layer cortical neuron formation. These phenotypes were mediated by the embryonic expansion of basal neural progenitor cells (NPCs) via deregulation of a ß-catenin/Brn2/Tbr2 transcriptional cascade. Transient pharmacological activation of the canonical Wnt pathway during this period of early corticogenesis rescued the ß-catenin/Brn2/Tbr2 transcriptional cascade and the embryonic brain phenotypes. Remarkably, this embryonic treatment prevented adult behavioral deficits and partially rescued abnormal brain structure in Dvl mutant mice. Our findings define a mechanism that links fetal brain development and adult behavior, demonstrating a fetal origin for social and repetitive behavior deficits seen in disorders such as autism.

Dysfunction in GABA signalling mediates autism-like stereotypies and Rett syndrome phenotypes.

Mutations in the X-linked MECP2 gene, which encodes the transcriptional regulator methyl-CpG-binding protein 2 (MeCP2), cause Rett syndrome and several neurodevelopmental disorders including cognitive disorders, autism, juvenile-onset schizophrenia and encephalopathy with early lethality. Rett syndrome is characterized by apparently normal early development followed by regression, motor abnormalities, seizures and features of autism, especially stereotyped behaviours. The mechanisms mediating these features are poorly understood. Here we show that mice lacking Mecp2 from GABA (γ-aminobutyric acid)-releasing neurons recapitulate numerous Rett syndrome and autistic features, including repetitive behaviours. Loss of MeCP2 from a subset of forebrain GABAergic neurons also recapitulates many features of Rett syndrome. MeCP2-deficient GABAergic neurons show reduced inhibitory quantal size, consistent with a presynaptic reduction in glutamic acid decarboxylase 1 (Gad1) and glutamic acid decarboxylase 2 (Gad2) levels, and GABA immunoreactivity. These data demonstrate that MeCP2 is critical for normal function of GABA-releasing neurons and that subtle dysfunction of GABAergic neurons contributes to numerous neuropsychiatric phenotypes.

Autism-like socio-communicative deficits and stereotypies in mice lacking heparan sulfate.

Heparan sulfate regulates diverse cell-surface signaling events, and its roles in the development of the nervous system recently have been increasingly uncovered by studies using genetic models carrying mutations of genes encoding enzymes for its synthesis. On the other hand, the role of heparan sulfate in the physiological function of the adult brain has been poorly characterized, despite several pieces of evidence suggesting its role in the regulation of synaptic function. To address this issue, we eliminated heparan sulfate from postnatal neurons by conditionally inactivating Ext1, the gene encoding an enzyme essential for heparan sulfate synthesis. Resultant conditional mutant mice show no detectable morphological defects in the cytoarchitecture of the brain. Remarkably, these mutant mice recapitulate almost the full range of autistic symptoms, including impairments in social interaction, expression of stereotyped, repetitive behavior, and impairments in ultrasonic vocalization, as well as some associated features. Mapping of neuronal activation by c-Fos immunohistochemistry demonstrates that neuronal activation in response to social stimulation is attenuated in the amygdala in these mice. Electrophysiology in amygdala pyramidal neurons shows an attenuation of excitatory synaptic transmission, presumably because of the reduction in the level of synaptically localized AMPA-type glutamate receptors. Our results demonstrate that heparan sulfate is critical for normal functioning of glutamatergic synapses and that its deficiency mediates socio-communicative deficits and stereotypies characteristic for autism.

The relationship between challenging behaviours, mood and interest/pleasure in adults with severe and profound intellectual disabilities.

BACKGROUND: We investigated whether current mood and interest/pleasure ratings in adults with moderate to profound intellectual disabilities were predictive of challenging behaviour [self-injurious behaviour (SIB), aggressive/destructive behaviour and stereotypic behaviour] and vice versa. METHOD: In this combined cross-sectional and longitudinal study, staff members of a Hungarian residential facility completed translated versions of the Behaviour Problems Inventory-Short Form (BPI-S), the Challenging Behaviour Interview (CBI) and the Mood, Interest and Pleasure Questionnaire-Short Form (MIPQ-S) for 50 participants at two time points, approximately 4 to 5 months apart. RESULTS: Bivariate correlations from data concurrently assessed at Time-1 showed significant linear relationships between the SIB (both frequency and severity scores) and Interest/Pleasure sub-scales, and the Aggressive/Destructive Behaviour (severity scores) and the MIPQ-S Mood sub-scales (unadjusted for multiple correlations). All of these effects were found with the BPI-S data, but not with the CBI. Multiple regression analyses revealed that (1) low interest/pleasure assessed at Time-1 predicted high SIB (frequency and severity) at Time-2. (2) Interest/pleasure was not predictive of aggressive or stereotypic behaviour. (3) Mood at Time-1 did not predict any of the three types of behaviour problems at Time-2. (4) In reverse, high SIB (frequency and severity) at Time-1 predicted low interest/pleasure ratings at Time-2. (5) Surprisingly, frequent aggressive/destructive behaviour predicted high interest/pleasure. (6) Stereotypic behaviour scores at Time-1 did not predict interest/pleasure ratings at Time-2. Again, all of these effects were only found with the BPI-S data, but not with the CBI. Internal consistency, test-retest reliability and concurrent validity of the Hungarian versions of all three questionnaires had generally satisfactory outcomes. DISCUSSION: The fact that increasingly frequent and severe SIB was predicted by declining measures of interest/pleasure is consistent with previous studies. Contrary to those earlier studies, however, we found that SIB was not predicted by mood and that aggressive/destructive behaviour actually predicted future elevated mood. Implications for future research regarding the directional relationship between affective states such as mood and interest and pleasure, on the one hand, and challenging behaviour, on the other, were discussed.

Prefrontal seizures manifesting as motor stereotypies.

BACKGROUND: The definition of stereotypies traditionally does not include "epileptic automatisms." However repetitive, sometimes rhythmic behaviors can occur during frontal lobe seizures in a reproducible pattern for a given patient. Thus, the concept of a frontostriatal "motor loop" could be relevant to repetitive ictal behaviors. METHODS: We describe 17 patients with frontal lobe epilepsy who presented with motor and/or verbal stereotypies and who were explored using depth electrodes (stereoelectroencephalography [SEEG]) in the context of epilepsy presurgical evaluation. RESULTS: Motor patterns were typically reproducible between seizures for a given patient. Distal motor stereotypies were associated with anterior prefrontal localization, and proximal stereotypies were associated with posterior prefrontal localization. CONCLUSIONS: "Stereotypy" is a useful term to describe ictal repetitive behaviors produced by prefrontal seizure discharge. The expression of distal and proximal stereotypies follows a rostrocaudal gradient within the frontal lobes. Exploration of the cortical compartment of frontostriatal networks in epileptic patients offers a unique opportunity to study the mechanisms of stereotypies in vivo.

Intense imagery movements: a common and distinct paediatric subgroup of motor stereotypies.

AIM: The aim of this article is to describe a subgroup of children who presented with stereotyped movements in the context of episodes of intense imagery. This is of relevance to current discussions regarding the clinical usefulness of diagnosing motor stereotypies during development. METHOD: The sample consisted of 10 children (nine males, one female; mean age 8y 6mo [SD 2y 5mo], range 6-15y). Referrals were from acute paediatricians, neurologists, and tertiary epilepsy services. Children were assessed by multidisciplinary teams with expertise in paediatric movement disorders. RESULTS: Stereotypies presented as paroxysmal complex movements involving upper and lower limbs. Imagery themes typically included computer games (60%), cartoons/films (40%), and fantasy scenes (30%). Comorbid developmental difficulties were reported for 80% of children. Brain imaging and electrophysiological investigations had been conducted for 50% of the children before referral to the clinic. INTERPRETATION: The descriptive term 'intense imagery movements' (IIM) was applied if (after interview) the children reported engaging in acts of imagery while performing stereotyped movements. We believe these children may form a common and discrete stereotypy subgroup, with the concept of IIM being clinically useful to ensure the accurate diagnosis and clinical management of this paediatric movement disorder.

Functional properties of behaviour problems depending on level of intellectual disability.

BACKGROUND: Behaviour problems are common among individuals with intellectual disabilities (ID) especially in those with more severe forms. The determination of the functional profile of a targeted behaviour has important implications for the design of customised behavioural interventions. METHOD: We investigated the relationship between the level of ID and the functional profile of aggression, stereotypy and self-injurious behaviour (SIB) using the Questions about Behavioural Function (QABF). Two staff members at two time points completed the QABF for each of 115 adults with varying levels of ID participating in a day training and habilitation programme. RESULTS AND CONCLUSIONS: Our results suggest that there is a differential relationship between the functions of behaviour problems and level of ID. While SIB is more often seen by raters to be maintained by escape of social demands and by attaining access to tangible items with the decline of the intellectual level, aggressive and stereotypic behaviours were identified more often as serving multiple functions equally across functioning level.

Leg stereotypy syndrome: phenomenological and quantitative analysis.

BACKGROUND: Leg stereotypy syndrome (LSS) is a very common, yet underrecognized condition. The pathophysiology of the condition is not well understood. OBJECTIVE: To evaluate and describe the visual kinematic characteristics of the repetitive leg movements in individuals with LSS. METHODS: In this study, we identified and videotaped individuals diagnosed with LSS at the Parkinson's Disease Center and Movement Disorders Clinic, Baylor College of Medicine, Houston, Texas between 2000 and 2023. Only patients with LSS and without any co-morbidities were included in the study. Their medical records were carefully reviewed, and the demographic and clinical data were entered into a database. Video recordings of the repetitive leg movements were then analyzed using TremAn software. RESULTS: We identified 14 individuals with LSS who were videotaped at our center. The videos of the 5 cases were too brief and therefore not suitable for TremAn quantitative analysis. The remaining 9 individuals exhibited regular rhythmic oscillations of the legs. Among these, two individuals displayed rhythmic movements only in video segments where their legs were in crossed positions. The other 7 individuals had regular rhythmic oscillations, always with the toes resting on the floor with the heels raised. Frequency analysis showed values between 4.5 and 6.5 Hz, fairly consistent with a variance below 0.5 Hz in individual cases. The oscillation frequency changed from 5.7 Hz to 2.7 Hz while standing. CONCLUSION: In this study, 6 of 9 individuals with LSS showed 4.5-6.5 Hz regular rhythmic leg movements. Studies involving a larger LSS population with additional electrophysiological evaluations are needed to obtain further insights into this common movement disorder.

Head stereotypies in STXBP1 encephalopathy.

STXBP1 encephalopathy is associated with a range of movement disorders. We observed head stereotypies in three patients. These comprised a slow (<1Hz), high-amplitude, horizontal, 'figure-of-eight' pattern, beginning at age 4-6 years and resulting in neck muscle hypertrophy, in two males; a faster (2-3Hz), side-to-side, 'no' movement, starting at the age of 9 years 6 months was observed in one female. Upper limb and truncal stereotypies and vocalization occurred intermittently with the head movements. The stereotypies increased with excitement but settled with concentration and sleep. Head and upper limb stereotypies are valuable clinical clues to the diagnosis of STXBP1 encephalopathy in patients with profound impairments.

Hand stereotypies distinguish Rett syndrome from autism disorder.

BACKGROUND: Rett syndrome (RTT) and autism disorder (AD) are 2 neurodevelopmental disorders of early life that share phenotypic features, one being hand stereotypies. Distinguishing RTT from AD often represents a challenge, and given their distinct long-term prognoses, this issue may have far-reaching implications. With the advances in genetic testing, the contribution of clinical manifestations in distinguishing RTT from AD has been overlooked. METHODS: A comparison of hand stereotypies in 20 children with RTT and 20 with AD was performed using detailed analyses of videotaped standardized observations. RESULTS: Striking differences are observed between RTT and AD children. In RTT, hand stereotypies are predominantly complex, continuous, localized to the body midline, and involving mouthing. Conversely, in AD children, hand stereotypies are simple, bilateral, intermittent, and often involving objects. CONCLUSIONS: These results provide important clinical signs useful to the differential diagnosis of RTT versus AD, especially when genetic testing for RTT is not an option.

Key role of striatal cholinergic interneurons in processes leading to arrest of motor stereotypies.

Motor stereotypy is a key symptom of various disorders such as Tourette's syndrome and punding. Administration of nicotine or cholinesterase inhibitors is effective in treating some of these symptoms. However, the role of cholinergic transmission in motor stereotypy remains unknown. During strong cocaine-induced motor stereotypy, we showed earlier that increased dopamine release results in decreased acetylcholine release in the territory of the dorsal striatum related to the prefrontal cortex. Here, we investigated the role of striatal cholinergic transmission in the arrest of motor stereotypy. Analysis of N-methyl-d-aspartic acid-evoked release of dopamine and acetylcholine during declining intensity of motor stereotypy revealed a dissociation between dopamine and acetylcholine release. Whereas dopamine release remained increased, the inhibition of acetylcholine release decreased, mirroring the time course of motor stereotypy. Furthermore, pharmacological treatments restoring striatal acetylcholine release (raclopride, dopamine D2 antagonist; intraperitoneal or local injection in prefrontal territory of the dorsal striatum) rapidly stopped motor stereotypy. In contrast, pharmacological treatments that blocked the post-synaptic effects of acetylcholine (scopolamine, muscarinic antagonist; intraperitoneal or striatal local injection) or induced degeneration of cholinergic interneurons (AF64A, cholinergic toxin) in the prefrontal territory of the dorsal striatum robustly prolonged the duration of strong motor stereotypy. Thus, we propose that restoration of cholinergic transmission in the prefrontal territory of the dorsal striatum plays a key role in the arrest of motor stereotypy.

Abnormal repetitive behaviours: shared phenomenology and pathophysiology.

BACKGROUND: Self-injurious behaviour (SIB) is a devastating problem observed in individuals with various neurodevelopmental disorders, including specific genetic syndromes as well as idiopathic intellectual and developmental disability. Although an increased prevalence of SIB has been documented in specific genetic mutations, little is known about the neurobiological basis of SIB. This makes vulnerability assessment and pharmacological treatment incredibly challenging. METHOD: Here we review evidence that SIB and other repetitive, invariant behaviours, such as stereotypy, compulsions and tics, share many phenotypic similarities, are often co-morbidly expressed and have common inducing conditions. This argues for shared or overlapping pathophysiology. As much more is known about the neurobiology of these related disorders, this should make the neurobiology of SIB a more tractable problem. RESULTS: Stereotypy, compulsions and tics are diagnostic for disorders that have received focused neurobiological investigation (autism, obsessive compulsive disorder, Tourette syndrome, respectively). In addition, animal models of these repetitive behaviours have been well characterised. Collectively, these studies have found that cortical basal ganglia circuitry dysfunction mediates repetitive behaviour. Moreover, these studies provide more detailed information and potentially testable hypotheses about specific aspects of the circuitry that may be operative in SIB. CONCLUSIONS: We can use available information from clinical and animal models to make more precise hypotheses regarding the particular pathophysiology driving SIB. The results of testing such hypotheses should generate pharmacological strategies that may prove efficacious in reducing SIB.