Elsevier

Psychiatry Research

Volume 243, 30 September 2016, Pages 143-146
Psychiatry Research

Neurological soft signs in Chinese adolescents with antisocial personality traits

https://doi.org/10.1016/j.psychres.2016.04.023Get rights and content

Highlights

  • ASP-traits adolescents had greater NSS severity than normal controls.

  • Seven neurological soft signs were more frequent in ASP-traits adolescents.

  • Sensory integration was positively associated with antisocial personality traits.

  • ASPD may have developmental abnormalities in the central nervous system.

  • Sensory integration may be the particular indicator of ASPD.

Abstract

The current study was designed to explore the specific relationship between neurologic soft signs (NSSs) and characteristics of antisocial personality traits in adolescents, and to investigate particular NSSs linked to certain brain regions in adolescents with antisocial personality traits. The research was conducted on 96 adolescents diagnosed with ASP traits (ASP trait group) using the ASPD subscale of the Personality Diagnostic Questionnaire for the DSM-IV (PDQ-4+) and 96 adolescents without traits of any personality disorder (control group). NSSs were assessed using the soft sign subscales of the Cambridge Neurological Inventory. Adolescents with ASP traits showed more motor coordination, sensory integration, disinhibition, and total NSSs than the control group. Seven NSSs, including stereognosia in right hand, finger agnosia and graphesthesia in both hands, left-right orientation, and go/no go stimulus, were significantly more frequent in teenagers with ASP traits. Sensory integration was positively associated with ASP traits. Adolescents with antisocial personality traits might have abnormalities in the central nervous system, and sensory integration might be the particular indicator of antisocial personality disorder.

Introduction

Neurologic soft signs (NSSs) were usually subtle but observable impairments in motor and sensory functions. They were neither localized to a specific region of the brain nor characteristic of any specific neurological condition (Bombin et al., 2005). However, recent studies using brain imaging technologies demonstrated that NSSs may be associated with specific brain regions or even brain connections. For instance, research indicated that higher rates of soft neurologic signs were associated with a reduction of gray matter volume of subcortical structures, including putamen, globus pallidus, and thalamus, in both patients with first-onset schizophrenia and healthy volunteers (Dazzan et al., 2006, Dazzan et al., 2004). Further, another study found that fist–edge–palm task, one of the NSSs, induced significant activations within the cortical networks that contain bilateral sensorimotor, supplementary motor area, left parietal, and the right cerebellum in healthy subjects (Chan et al., 2006, Rao et al., 2008).

Antisocial Personality Disorder (ASPD) develops mostly during childhood or early adolescence and persists into adulthood. It is characterized by dysfunctional interpersonal relationships, a lack of empathy and remorse, impulsivity, and aggression (Glenn et al., 2013). Several studies investigated the biological mechanisms underlying these behaviors. Neuroimaging studies found structural and functional abnormalities of people with ASPD. For example, Rankin et al. revealed that the medial orbitofrontal cortex (OFC) and ventral striatal structures contributed to empathy, and the right anterior temporal areas were essential for real-life empathic behavior (Rankin et al., 2006). Meantime, some research demonstrated the relationship between brain structure and impulsive aggressive behavior. Researchers found that aggressive impulsive behavior was associated with reduced metabolism in the orbitofrontal, anterior medial frontal, and left anterior frontal regions (Goyer et al., 1994). Hoptman et al. found that the inferior frontal white matter microstructure (Hoptman et al., 2002) and amygdalofrontal functional disconnectivity (Hoptman et al., 2010) was associated with aggressive and antisocial behavior. Further, reduced metabolism was found in the superior parietal cortex in aggressive patients (Hirono et al., 2000), and individuals with impulsive personality disorders (Siever et al., 1999).

There are some previous studies correlating NSSs and ASPDs or antisocial behavior. A study recruited inpatients with schizophrenia with violent behavior, and patients were classified into high (n=28), low (n=27), or no (n=34) violence groups. This study found that the high violence group showed more neurologic and neuropsychologic abnormalities than the other two groups in the area of integrative sensory and motor functions (Krakowski et al., 1989). Another study comprised 14 homicidal men with ASPD according to a forensic psychiatric examination. Ten healthy volunteers served as controls. The NSSs scores of antisocial offenders were dramatically increased as compared with normal controls (Lindberg et al., 2004). These aforementioned researches may indicate that antisocial behavior or ASPD was related to a certain neurophysiology deficit.

The Cambridge Neurological Inventory was a clinical instrument for assessment of soft neurologic signs, and it consisted of three subscales: the motor coordination, sensory integration, and disinhibition. These subscales have been devised to investigate the putative areas of the prefrontal, parietal, and frontal lobes, respectively (Chen et al., 1995, Chan and Gottesman, 2008). Given the aforementioned researches, the purpose of this study was to investigate the specific relationship between NSSs and characteristics of antisocial personality traits in adolescents, and to explore the particular NSSs linked to certain brain regions in adolescents with antisocial personality traits. In addition, considering adolescence was a vulnerable period and facilitates the start of risk behaviors (Garcia and Costa, 2008), such as cannabis abuse (Dervaux et al., 2010), smoking, unprotected sex, and so on, and higher levels of psychopathic traits in adolescence predicted violent recidivism (Gretton et al., 2004), we chose teenagers as our experimental subjects.

Section snippets

Participants

The adolescents were recruited from five cities in China (Beijing, Changsha, Suzhou, Chengdu, and Yinchuan). Adolescents or their family members with a history of psychotic illness were excluded on the basis of a brief questionnaire. Eventually, 2861 effective questionnaires were collected, comprising 1395 boys and 1466 girls. Permission was taken from the Medical Ethics Committee of Central South University, and written informed consent was obtained from all participants.

Personality Diagnostic Questionnaire-4+, PDQ-4+

Antisocial personality

Demographics

Ninety-six adolescents with only antisocial personality traits were detected according to the cut-off score of antisocial personality disorder subscale of PDQ-4+. Further, 96 healthy controls were recruited by random selection from the enrolled teenagers without any pathological personality traits we detected, and they were matched for age and gender. Meantime, none of the subjects reported cannabis or other drug abuse. As demonstrated in Table 1, there were no significant between-group

Discussion

The results revealed that adolescents with antisocial personality traits exhibited a higher prevalence of NSSs than normal control participants. The ASP group showed greater motor coordination, sensory integration, disinhibition, and total NSSs than the normal group. Our study suggested that neural abnormality was involved in development of ASPD. The present findings were also similar to those from previous studies focused on antisocial personality or antisocial behavior (Krakowski et al., 1989

Conflict of interest

None of the authors reports conflicts of interest.

Acknowledgments

This study was supported by grants from the National Key Technologies R&D Program in the 11th 5-year plan of China (Grant No. 2009BAI77B02); the National Natural Science Foundation of China (Grant No. 81401128).

References (29)

  • Y.P. Wang et al.

    Screening cluster A and cluster B personality disorders in Chinese high school students

    BMC Psychiatry

    (2013)
  • I. Bombin et al.

    Significance and meaning of neurological signs in schizophrenia: two decades later

    Schizophr. Bull.

    (2005)
  • L. Cai et al.

    Neurological soft signs and their relationship with measures of executive function in Chinese adolescents

    J. Dev. Behav. Pediatr.

    (2013)
  • G.A. Calvert

    Crossmodal processing in the human brain: insights from functional neuroimaging studies

    Cereb. Cortex

    (2001)
  • Cited by (0)

    View full text