Presence Of Neurological Soft Signs Research Articles

Neurological soft signs as trait markers of a subset of patients with obsessive-compulsive disorder with low insight and altered cognitive abilities

Neurological soft signs (NSS) are subtle motor control impairments that include involuntary movements and abnormalities of motor coordination, sensory integration and lateralization. They engage different brain networks, including the prefrontal networks that support the higher cognitive functions that are dysfunctional in obsessive-compulsive disorder (OCD). This study investigated the relationships between the presence of NSS and patients' severity of OCD symptoms, insight, and treatment resistance in a sample of 63 patients. Treatment-resistance was assessed considering all the treatments the patients received during the course of their disease. The four dimensions of OCD defined in the dimensional obsessive-compulsive scale were considered. Links between the patients’ cognitive abilities and NSS were assessed using tests targeting specifically the core components of executive functions.As expected, OCD patients displayed more NSS than individually matched control participants. In OCD patients, high NSS scores were associated with poor insight and lower cognitive abilities. Multiple regression analysis identified worse visuospatial working memory, attentional control, and verbal fluency as predictive factors of high NSS scores among cognitive functions. Unexpectedly, the patients displaying symptoms in the contamination/washing dimension displayed less NSS than the other patients. In contrast, neither the severity of OCD symptoms nor long-range treatment resistance was significantly related to patients’ NSS scores. Altogether, our findings suggest that high NSS scores may be a trait marker of a subset of OCD patients with low insight and particularly altered cognitive abilities who would not express the contamination/washing dimension of the pathology.

Presence of neurologic signs in children with neurofibromatosis type 1

Neurofibromatosis type 1 is a common neurogenetic disorder affecting nervous system, caused by germiline mutations of the NF1 gene. Although the clinical diagnosis of NF1 is defined by presence of cafe-au-laits spots, freckling and benign tumors (neurofibromatosis), neurocognitive impairment and neuropsychiatric disorders are reported in comorbidity. Children with NF1 show higher incidence of executive deficits, such attention, response inhibition, executive planning and problem solving, working memory, and learning impairment. In this study we examine the presence of neurological soft signs and planning function in subjects with NF1. The NSS are minor motor and sensory abnormalities without focal brain damage. Eleven drug naïve children between 7-15 years with clinical and molecular diagnosis of NF are matched to 11 healthy controls to ass the presence of neurological soft signs and planning executive functions. NSS were assessed using Physical and Neurological Examination for Subtle Signs and the Tower of London task is performance test to assess the capacity of planning, organization and execution of a work. Our results revealed highest rate of NSS and planning deficit in children with NF1 compared to healthy controls. The motor abnormalities and planning deficit are possible markers to confirm that NF1 could be considering a neurodevelopmental disorder.

Reclassification of patients with tremor syndrome and comparisons of essential tremor and essential tremor-plus patients.

The new essential tremor (ET)-plus nomenclature was proposed by the 2018 Tremor Consensus Criteria. However, few studies have adopted this usage and the clinical differences between ET and ET-plus remains unclear. To address this issue, we reclassified and compared the characteristics of ET and ET-plus patients in a large Chinese tremor cohort. In this cross-sectional observational study, 766 patients originally diagnosed with ET underwent neurological examination. Scale ratings were used to evaluate motor and non-motor symptoms, and quality of life (QoL). We then reclassified the ET cohort and compared demographic and clinical characteristics between ET and ET-plus patients. A logistic regression analysis was used to explore whether the presence of neurological soft signs in ET-plus was associated with tremor severity or QoL. Among 665 clinically confirmed ET syndrome patients, 274 were ET and 391 were ET-plus. The most prevalent neurological soft sign was resting tremor. ET-plus patients were older, had older age at onset and longer disease duration. ET-plus patients recorded higher scores in tremor severity evaluations and lower in cognitive evaluations, whereas a higher proportion of patients presented with depression or anxiety symptoms. Resting tremor and questionable cerebellar signs were associated with tremor severity. Cognitive impairment was associated with worse QoL. ET-plus patients were older, had longer disease durations, worse tremor manifestations, and more distinct non-motor symptoms. Certain additional soft signs of ET-plus were associated with tremor severity or worse QoL. ET-plus patients may include advanced ET patients with additional neurological soft signs presenting along with disease progression.

Neurological soft signs correlation with symptom severity in borderline personality disorder

BackgroundBorderline personality disorder (BPD) is a severe psychiatric disorder with multiple psychopathological domains; so studying the correlation of clinical or behavioral data with underlying structural and functional neurological findings in BPD is the focus of interest in recent years.The aim of our study was to compare the presence of neurological soft signs (NSS) in patients with borderline personality disorder with their presence in normal controls, and to correlate the severity of different symptoms of BPD with the presence of NSS through a case-control study which was conducted on 30 patients and 30 matching controls recruited from Al Kasr Al Ainy Hospital, Cairo University, Egypt. All subjects were assessed by the Borderline Personality Questionnaire, the Barratt Impulsivity Scale-11, the Brief Non-Suicidal Self-Injury Assessment tool, and the Cambridge Neurological Inventory.ResultsThe BPD group had significantly higher total NSS scores, primitive reflexes subscale score, and sensory integration subscale scores. There was also a positive correlation between NSS and overall severity of borderline symptoms.ConclusionsThe increased rates of NSS were associated with specific clinical symptoms in BPD including suicidality, self-harm, emptiness, and quasi-psychosis. Impulsivity was found to have the highest correlation with NSS.

S187. EXPLORING NEURODEVELOPMENTAL AND FAMILIAL ORIGINS OF NEUROLOGICAL SOFT SIGNS IN SCHIZOPHRENIA

BackgroundThe neurodevelopmental hypothesis is the most widely regarded framework for understanding the development of schizophrenia. One of the most commonly cited pieces of evidence for this theory is the presence of neurological soft signs (NSS) in individuals prior to the onset of psychosis. Increased NSS is also reported in unaffected individuals with a family history of schizophrenia, suggesting that NSS may also have a familial component. Although much research has implicated reduced grey matter volume (GMV) in association with these signs, a subcomponent of volume, known as gyrification, has been poorly researched. Given that gyrification develops predominantly in prenatal life it may be particularly susceptible to a neurodevelopmental abnormality. The aims of this study were to investigate the neurodevelopmental and familial underpinnings of NSS in schizophrenia. Specifically, we examined the brain structural correlates, at both the level of GMV and gyrification, of NSS in individuals with schizophrenia, their unaffected relatives and healthy controls. We aimed to determine whether gyrification better predicted NSS severity than GMV, and whether the relationship between brain structure and NSS were present in a step-wise manner across the diagnostic groups.MethodsThe sample consisted of individuals with schizophrenia (N=66), their unaffected relatives (N=27) and healthy controls (N=53). NSS was assessed with the Neurological Evaluation Scale (NES), and GMV and gyrification were extracted from MRI using the FreeSurfer imaging suite. A series of analysis of covariance were used to compare NES scores and brain measures between the groups. Separate linear regression analyses were used to assess whether whole-brain GMV and gyrification predicted NES above a covariate-only model. Moderation analyses were used to assess whether the relationship between NES and brain structure were different between the diagnostic groups. Error control was achieved with a false discovery rate of 5%.ResultsNES was significantly higher in schizophrenia patients than relatives (p<.0001), who were in turn significantly higher than controls (p=.034). With the groups combined, lower GMV (p<.0001), as well as lower gyrification (p=.004), predicted higher NES above a covariate-only model. GMV predicted greater variance in NSS in comparison to gyrification, explaining an additional 20.3% of the variance in NES, in comparison to the additional 5.5% of variance in NES explained by gyrification. Diagnostic group moderated the association between GMV and NES (p=.019), but not between gyrification and NES (p=.245). Follow-up tests revealed that lower GMV was associated with higher NES in schizophrenia (t=-4.5, p<.0001) and relatives (t=-2.5, p=.015) but not controls (t=-1.9, p=.055).DiscussionOur findings indicate that NSS is heritable, being present in patients with established schizophrenia, and to a lesser extent, in unaffected relatives. Consistent with previous research, we revealed that GMV predicted NSS severity, suggesting that abnormalities in volume may underlie these signs. We additionally found that gyrification predicted, although to a lesser extent than volume, NSS severity, providing some support for schizophrenia being of possible neurodevelopmental origin. Evidence for an association between volume and NSS in relatives, whom are not confounded by illness-related factors such as medication and symptom severity, indicates a familial contribution to the neural underpinnings of NSS. Together, our study suggests that there may be various aetiological pathways underlying soft signs across the schizophrenia diathesis, some that may be of familial or neurodevelopmental origin.

Neurological Soft Signs in Patients with Attention Deficit Hyperactivity Disorder Aged 6 to 18 Years Old at a University Hospital: A Cross-sectional Study

Attention deficit hyperactivity disorder (ADHD) is a common neurodevelopmental disorder in children persisting into adulthood. Evidence suggests that the condition is etiologically related to delayed brain maturation. The detection of the presence of neurological soft signs can be a means to assess neuromaturation. The objective of this study was to assess the prevalence of neurological soft signs in ADHD patients and determine any correlation between the presence of neurological soft signs with age, gender, severity and type of ADHD which could give further insights into this disorder.

Cortical thickness correlates of minor neurological signs in patients with first episode psychosis

Neurological soft signs (NSS) are subtle abnormalities of motor and sensory function that are present in the absence of localized brain pathological lesions. In psychoses they have been consistently associated with a distinct pattern of cortical and subcortical brain structural alterations at the level of the heteromodal cortex and basal ganglia. However, a more specific and accurate evaluation of the cytoarchitecture of the cortical mantle could further advance our understanding of the neurobiological substrate of psychosis.We investigated the relationship between brain structure and NSS in a sample of 66 patients at their first episode of psychosis. We used the Neurological Evaluation Scale for neurological assessment and high-resolution MRI and Freesurfer to explore cortical thickness and surface area. Higher rates of NSS were associated with a reduction of cortical thickness in the precentral and postcentral gyri, inferior-parietal, superior temporal, and fusiform gyri. Higher rates of NSS were also associated with smaller surface areas of superior temporal gyrus and frontal regions (including middle frontal, superior and orbito-frontal gyri). Finally, more sensory integration signs were also associated with larger surface area of the latero-occipital region.We conclude that the presence of NSS in psychosis is associated with distinct but widespread changes in cortical thickness and surface area, in areas crucial for sensory-motor integration and for the fluid execution of movement. Studying these morphological correlates with advanced neuroimaging techniques can continue to improve our knowledge on the neurobiological substrate of these important functional correlates of psychosis.

Neurological Soft Signs in Schizophrenia: An Update on the State- versus Trait-Perspective.

Neurological soft signs (NSS) represent minor neurological signs, which indicate non-specific cerebral dysfunction. In schizophrenia, their presence has been documented extensively across all stages of the disease. Until recently, NSS were considered an endophenotype or a trait phenomenon. During the past years, however, researchers report fluctuations of the NSS scores. To further clarify the question whether NSS exhibit state or trait components or both, studies that have investigated NSS longitudinally were reviewed. Studies which have assessed NSS longitudinally in adults suffering from schizophrenia, were searched for. The time frame was January 1966 to June 2017. Studies on teenagers were excluded because of interferences between brain maturation and pathology. Twenty-nine follow-up studies were identified. They included patients during different stages of their illness and mainly used established instruments for NSS assessment. Patients with a first episode or a remitting course predominantly show a decrease of NSS over time, whereas a worsening of NSS can be found in the chronically ill. It was shown that change of NSS total scores over time is predominantly caused by motor system subscales and to a lesser extent by sensory integration scales. With respect to medication, the majority of studies agree on a relationship between medication response and improvement of NSS while the type of antipsychotic does not seem to play a major role. Moreover, where information on side-effects is given, it does not favor a strong relationship with NSS. However, NSS seem to correlate with negative and cognitive symptoms. Studies manifest a conformity regarding the presence of NSS in schizophrenia patients on the one hand. On the other hand, fluctuations of NSS scores have been widely described in subgroups. Taken together results strongly support a state-trait dichotomy of NSS. Thus, the usage of NSS as an endophenotype has to be called into question.

Dopamine dysfunction in 22q11 deletion syndrome: possible cause of motor symptoms.

22q11 Deletion syndrome (22q11DS) is a neurogenetic disorder, resulting from a hemizygous microdeletion on the long arm of chromosome 22. In 22q11DS, the phenotypic expression is highly variable. Approximately one-third of all individuals with 22q11DS develop schizophrenia-like psychotic disorder. Among the genes in the deleted region, catechol-O-methyltransferase (COMT) has a particular relevance for psychiatric disorders: lower COMT enzymatic activity decreases the clearance of dopamine (DA), yielding higher levels of catecholamines in the central nervous system. Deficits in myelinogenesis and dysfunctions in the DA system could justify the white matter abnormalities in motor/premotor circuits described in 22q11DS. The alterations in DA could determine the high incidence of psychiatric disorders and the presence of neurological soft signs in 22q11DS. Neurological soft signs are defined as non-normative performance on an examination of motor and sensory tasks without focal neurological deficits. COMT haploinsufficiency, DA dysfunction, and white matter abnormalities may contribute toward the presence of neurological soft signs in 22q11DS.

A qualititative study of neurological soft signs in obsessive compulsive disorder and effect of comorbid psychotic spectrum disorders and familiality on its expression in Indian population.

Obsessive Compulsive Disorder (OCD) is one of the most common psychiatric disorders, with lifetime prevalence of 2%-3% and is known to lie on a spectrum continuous with Schizophrenia and other affective psychosis. Neurological Soft Signs (NSS) have been reported to be higher in both Schizophrenia and affective psychosis, like bipolar disorder, and their first degree relatives but in OCD, the results have been inconsistent. It remains unclear if NSS occur at even higher rates in individuals who have a co-morbidity for OCD and either schizophrenia or bipolar disorder, as it might be expected if a broader neurodevelopmental hit underlies the pathophysiology of both OCD and these disorders. To assess and compare NSS in patients of OCD, OCD with Psychotic spectrum disorders (OCD-PSD), first degree relatives of OCD (FDR of OCD) and healthy controls. 90 subjects each were recruited in four groups- OCD, OCD-PSD, FDR of OCD and healthy controls, as per the pre-defined inclusion and exclusion criteria for each group. Diagnosis was made as per ICD-10 criteria and Cambridge Neurological Inventory, Part-2 was applied. This study found statistically significant difference between the severity of NSS among these groups. There was also a significant difference in presence of NSS in OCD with PSD group and OCD group. A greater abnormality of NSS in FDR of OCD compared to healthy controls was found. This difference in proportions and severity of NSS between groups points towards an underlying common neurobiological and etiopathological underpinning between OCD with and without comorbid PSDs and their first degree relatives.

Is Hypoesthesia of the Malleolus a Subtle Neurological Sign in Anxiety?

This study examined the presence of neurological soft signs, an accessible diagnostic instrument, in patients with anxiety. Individuals with anxiety were more likely to manifest hypoesthesia than healthy controls, and patients who showed hypoesthesia exhibited greater symptoms of anxiety and depression.

Neurological soft signs with respect to type of symptoms in patients with schizophrenia

Introduction Neurological soft signs have been documented to occur in up to 60% of patients with schizophrenia and have been found even in neuroleptic-naive patients. Aims The aims of the study were to illustrate the presence of neurological soft signs among patients with schizophrenia and to show any relationship between neurological soft signs and type of symptoms. Patients and methods One hundred patients with schizophrenia were selected consecutively in a cross-sectional study. The patients were assessed using the Structured Clinical Interview for Diagnostic and statistical manual of mental disorders (DSM) Axis of Disorders, Positive and Negative Syndrome Scale, complete neurological examination, and Cambridge Neurological Inventory for soft sign examinations (primitive reflexes, repetitive movement, sensory integration), and Trail Making Test. Results The main finding in this study indicates that the patients with schizophrenia have neurological impairment. There are positive correlations between soft neurological signs and positive symptoms in paranoid type, other types, and with the total; these indicate that neurological soft signs are more prominent in patients with positive symptoms than in those with negative symptoms. Conclusion Neurological Soft Signs (NSS) occur in a majority of the schizophrenia patient population and are largely distinct from symptomatic and cognitive features of the illness. Neurological signs in patients with schizophrenia are associated with prominent negative symptoms, relatively poor psychosocial performance, and significantly more cognitive impairment.

Clinical and neuropsychological correlation in patients with rolandic epilepsy

To evaluate the presence of neurological soft signs (NSS) and to correlate them with the Wechsler Intelligence Scale for Children (WISC III) in patients with rolandic epilepsy (RE). Forty children and adolescents aged between 9 and 15 years were studied. They were divided into two groups: G1 - patients with RE (n=20) - and G2 - healthy controls without epilepsy (n=20). They were assessed with the Quick Neurological Screening Test (QNST II) - clinical trial to search for NSS -, and the WISC III - neuropsychological test. No statistical difference between groups was found in WISC III and QNST II. However, children with poorer motor skills had worse performance in the QNST II and also in the execution intelligence quotient - IQ (p=0.001) and in total IQ (p=0.004), thus showing a positive correlation between them. The QNST II is a good screening tool for the neurologist to detect abnormalities in fine motor skills.

Neurological soft signs as an endophenotype in an African schizophrenia population – a pilot study

The use of endophenotypes, such as neurological soft signs (NSS), is advocated as one possible method to elucidate the heterogeneity of schizophrenia. Exploring the associations between NSS and specific illness symptoms has revealed some trends, although results have been conflicting. To date, such studies have been conducted largely on Caucasian populations and our pilot study represents the first attempt to gather such data in a homogenous African population. Fifty-one patients, all of Xhosa ethnicity and participating in a larger schizophrenia genetic study were recruited. NSS were evaluated using a modified Neurological Evaluation Scale. Data were analysed using SPSS with the strength of the overall relationships between NES groups and SANS and SAPS components analyzed by means of canonical correlation analysis. The canonical correlation of SANS domains (excluding asociality) with the NES conceptual groups was 0.53 (SE=0.11, p=0.024) and of the SAPS domains 0.38 (SE=0.13, p=0.943). Our results suggest a correlation between negative symptoms of schizophrenia and the presence of NSS, supporting the recruitment of a larger sample to more comprehensively evaluate a possible role for NSS as an endophenotype in the Xhosa schizophrenia population. Taking into account that NSS evaluations allow for inexpensive, relatively easy-to-do objective evaluations, this method presents us with a valuable research tool that can be used effectively within our under-resourced environment to help inform on the neurobiological substrate of schizophrenia.

Neurological soft signs in children with attention deficit hyperactivity disorder.

Context:Attention deficit hyperactivity disorder (ADHD) is a common neurodevelopmental disorder with wide repercussions. Since it is etiologically related to delayed maturation, neurological soft signs (NSS) could be a tool to assess this. Further the correlation of NSS with severity and type of ADHD and presence of Specific Learning Disability (SLD) would give further insight into it.Aims:To study neurological soft signs and risk factors (type, mode of delivery, and milestones) in children with ADHD and to correlate NSS with type and severity of ADHD and with co-morbid Specific Learning Disability.Settings and Design:The study was carried out in Child care services of a tertiary teaching urban hospital. It was a cross-sectional single interview study.Materials and Methods:52 consecutive children diagnosed as having ADHD were assessed for the presence of neurological soft signs using Revised Physical and Neurological Examination soft Signs scale (PANESS). The ADHD was rated by parents using ADHD parent rating scale.Statistical Analysis:The data was analyzed using the chi-squared test and Pearson's co-relational analysis.Results and Conclusions:Neurological soft signs are present in 84% of children. They are equally present in both the inattentive-hyperactive and impulsive-hyperactive types of ADHD. The presence of neurological soft signs in ADHD are independent of the presence of co-morbid SLD. Dysrrhythmias and overflow with gait were typically seen for impulsive-hyperactive type and higher severity of ADHD is related to more errors.

Neurological Soft Signs and Corpus Callosum morphology in schizophrenia

Objective: Neurological Soft Signs (NSS) have been found to be more prevalent in schizophrenic patients. A breakdown in intracortical functional connectivity, including interhemispheric communication, has been suggested in the pathogenesis of schizophrenia. Indeed, problems with interhemispheric information transfer via the Corpus Callosum (CC) have been documented in schizophrenics. Our study goal was to relate NSS to CC morphology. Methods: CC Magnetic Resonance Imaging (MRI) measurements were collected from 29 right-handed male schizophrenia inpatients. NSS were evaluated employing the Neurological Evaluation Scale (NES). We examined the scores obtained from the NES total and the three NES subscales: Integrative Sensory Function, Motor Coordination, and Sequencing Of Complex Motor Acts. We compared CC morphology of patients with “high” NSS with that of patients with “low” NSS. Correlation analyses were performed to further clarify the relationship between CC size, NSS, and total lifetime antipsychotic consumption. Results: Patients with “high” scores at the Sequencing Of Complex Motor Acts subscale showed a smaller CC rostral body, whereas patients with “high” scores at the Integrative Sensory Function subscale showed a smaller CC splenium. For both the NES total and the Sequencing Of Complex Motor Acts subscale, “high” scores were accompanied by an increase of the CC genu. Correlation analyses revealed a significant inverse correlation between the CC rostral body size and the Sequencing Of Complex Motor Acts subscale score. In addition, a significant positive correlation was shown between the CC genu size and both the NES total and the Sequencing Of Complex Motor Acts subscale scores. The presence of NSS and the accompanying CC structural abnormalities were independent on antipsychotic treatment. Conclusions: Our data provide evidence for an association between NSS and CC morphology and further support the hypothesis of a disturbed interhemispheric functional connectivity in schizophrenia.

L’enfance des schizophrènes : revue de la littérature

Introduction Pre-morbid antecedents in schizophrenia have been studied for some time now more particularly as potential markers of vulnerability. What are the tell-tale signs in some of the patient's childhood? The authors suggest a non-exhaustive review of the literature on this subject. Method The authors reviewed the literature (English and French) of prospective and retrospective studies. Results Many fields appear to be impaired during the childhood of some schizophrenic patients, fields such as: developmental abnormalities, speech impairments, social interactions, behaviour, cognitive functioning. The authors also noticed the presence of neurological soft signs and para-clinical abnormalities. Discussion The authors suggest a critical and synthetic review of existing data: what can be retained of this data? The authors also discuss the evolution of these signs and their interaction with the evolution of the disease itself. Conclusion Many of these signs were noticed in several children who later developed schizophrenia. For many authors, the more important these signs are, the more severe the disease will be. These pre-morbid antecedents give rise to theoretical questions and open perspectives concerning an early diagnosis of schizophrenia.

Signes neurologiques mineurs chez les patients schizophrènes et leurs apparentés non malades

Neurological soft signs (NSS) are subtle neurological signs indicating non specific cerebral dysfunction. Several studies have found an excess of NSS in schizophrenic patients compared to healthy subjects. Although NSS have been consistently reported in schizophrenic patients, their clinical relevance and their relation to functional impairment and severity of this disease are not well-clarified. In addition, the presence of NSS in schizophrenic patient's relatives suggests that they could be associated with the genetic liability. To determine the prevalence and scores of NSS in schizophrenic patients and their nonaffected siblings and to examine the clinical correlates of NSS in the schizophrenic patients. Sixty-six schizophrenic patients (50 males and 16 females, mean age=31.16+/-7.17 years), were compared to 31 of their nonaffected siblings (22 males and nine females, mean age=32.19+/-5.88 years) and to 60 controls subjects (40 males and 20 females, mean age=30.70+/-6.54 years) without family psychiatric history. NSS were assessed with Krebs et al.'s neurological soft signs scale. It is a comprehensive and standardized scale consisting of 23 items comporting five factors: motor coordination, motor integration, sensory integration, quality of lateralization and involuntary movements or posture. The Simpson and Angus scale for extrapyramidal symptoms was also rated. Clinical assessment of the schizophrenic patients was conducted using the positive and negative syndrome scale (PANSS), clinical global impressions (CGI) and global functioning evaluation (GAF). Psychiatric disorders were ruled out among siblings of schizophrenic patients and control subjects by psychiatric review evaluation, according to the DSM-IV check list. When the total NSS score of 11.5 was considered the cut-off point, the prevalence of NSS was 96.9% in the schizophrenic patients versus 35.5% in the nonaffected siblings (p<0.0001). Schizophrenic patients had also significantly higher NSS total score and subscores than the siblings and control groups. The NSS total score was 19.51+/-5.28 in the schizophrenic patients, 10.77+/-3.38 in their nonaffected siblings and 4.23+/-2.07 in control subjects (p<0.0001). The NSS total score and subscores in the siblings group were intermediate between those of the schizophrenic patients and those of the control subjects. The motor coordination, motor integration and sensory integration subscores were higher in schizophrenic patients and their nonaffected siblings. The NSS total score correlated positively with the negative (p<0.0001) and disorganization symptoms (p=0.001) subscores and total score of PANSS (p=0.004). The PANSS total score and negative and disorganization subscores also correlated positively with the motor integration and quality of laterality subscores of NSS. The NSS total score was significantly correlated with severity of illness (p<0.0001), lower educational level (p=0.002) and poor global functioning (p=0.003). The association between NSS with negative and disorganization dimensions of schizophrenia supports that neurological dysfunction is an intrinsic characteristic of the illness and may distinguish a subgroup of patients with poor illness course and outcome. The NSS could be a trait marker useful in phenotypic characterization of schizophrenic patients and identification of vulnerability in genetically high-risk subjects.

The psychopathology of schizophrenia and the presence of neurological soft signs: a review

The symptoms of schizophrenia cluster in at least three subtypes: positive, negative, and disorganized. The study of these subtypes and their phenotypic markers may help our understanding of the pathophysiology of schizophrenia. Among the markers of schizophrenia are minor neurological signs, which are abnormalities in sensory and motor performance elicited by clinical examination. Evidence on whether neurological abnormalities are associated with a specific symptom subtype is considered. As recent studies have often evaluated individuals at their first psychotic episode who are antipsychotic naïve, a review would help to clarify whether neurological soft signs are part of a neurodysfunction that underlies schizophrenia rather than the consequence of degenerative processes or of long-term pharmacological treatment. A consistent association seems to emerge between an excess of neurological soft signs and severe negative symptoms. Signs associated with negative symptoms remain stable over time, and may characterize a subgroup of patients with poor illness course and outcome. Some signs, such as motor dysfunction, may be associated with a worse profile of positive symptoms, and may improve as symptoms improve. Too few studies have evaluated the association between neurological soft signs and disorganization symptoms to suggest or disconfirm any relationship. Finding an association between neurological soft signs and one (or more) dimension(s) of schizophrenia in never treated patients may explain which neurological dysfunction is an intrinsic characteristic of the illness. The comparability of future studies can be improved by using the same structured rating scale for neurological soft signs and psychopathology, and by a better characterization of patient samples.

Relative phase stability of bimanual and visuomanual rhythmic coordination patterns in children with a Developmental Coordination Disorder

A dynamic pattern approach is used to examine the relative phase stability of rhythmic coordination in 24 children with a Developmental Coordination Disorder (DCD) and 24 matched controls in two functionally different tasks – a within-subject task (bimanual coordination) and a subject-environment task (visuomanual coordination). The stability of basic rhythmic coordination patterns (in-phase and antiphase patterns) was tested by applying perturbations, and by increasing the movement frequency towards the frequency where a loss of stability occurred. Coordination patterns of children with DCD were less stable than those of controls, both in the bimanual and the visuomanual task. According to the dynamic model (Haken, H., Kelso, J.A.S., Bunz, H., 1985. Biological Cybernetics 51, 347–356; Kelso, J.A.S., Delcolle, J.D., Schöner, G., 1990. In: Jeannerod, M. (Ed.), Attention and Performance XIII: Motor Representation and Control. Lawrence Erlbaum, Hillsdale, NJ, pp. 139–169), this reduced stability is due to a weaker coupling strength between the oscillators that represent the rhythmic units involved in the tasks. Further, within the DCD group three subtypes were found on the basis of particularly poor stability in bimanual rhythmic coordination ( N=2), visuomanual rhythmic coordination ( N=4), or both ( N=7). These data were related to the presence of neurological soft signs in the DCD group, which did not reveal specific patterns of minor neurological dysfunction in these children. Theoretical and practical implications of these findings were discussed. PsycINFO classification: 2323; 2330; 3250; 3297