Jane McGillivray

Deep brain stimulation for treatment-resistant depression: Efficacy, safety and mechanisms of action

Deep brain stimulation (DBS), a neuromodulation therapy that has been used successfully in the treatment of symptoms associated with movement disorders, has recently undergone clinical trials for individuals suffering from treatment-resistant depression (TRD). Although the small patient numbers and open label study design limit our ability to identify optimum targets and make definitive conclusions about treatment efficacy, a review of the published research demonstrates significant reductions in depressive symptomatology and high rates of remission in a severely treatment-resistant patient group. Despite these encouraging results, an incomplete understanding of the mechanisms of action underlying the therapeutic effects of DBS for TRD is highlighted, paralleling the incomplete understanding of the neuroanatomy of mood regulation and treatment resistance. Proposed mechanisms of action include short and long-term local effects of stimulation at the neuronal level, to modulation of neural network activity.

Gender differences in emotionality and sociability in children with autism spectrum disorders

BackgroundFour times as many males are diagnosed with high functioning autism compared to females. A growing body of research that focused on females with autism spectrum disorder (ASD) questions the assumption of gender invariance in ASD. Clinical observations suggest that females with ASD superficially demonstrate better social and emotional skills than males with ASD, which may camouflage other diagnostic features. This may explain the under-diagnosis of females with ASD.MethodsWe hypothesised that females with ASD would display better social skills than males with ASD on a test of friendship and social function. One hundred and one 10- to 16-year-olds (ASD females, n = 25; typically developing (TD) females, n = 25; ASD males, n = 25; TD males, n = 26) were interviewed (using the friendship questionnaire (FQ)) with high scores indicating the child has close, empathetic and supportive relationships. One parent of each child completed the FQ to assess whether there are differences in perception of friendships between parents and children.ResultsIt was found that, independent of diagnosis, females demonstrated higher scores on the FQ than males. Further, regardless of gender, children with ASD demonstrated lower scores than TD children. Moreover, the effect of ASD was independent of gender. Interestingly, females with ASD and TD males displayed similar scores on the FQ.ConclusionsThis finding is supported by clinical reports that females with ASD have more developed social skills than males with ASD. Further research is now required to examine the underlying causes for this phenomenon in order to develop gender-appropriate diagnostic criteria and interventions for ASD.

Substance use by offenders with mild intellectual disability

This study compared the rate of self-reported alcohol and other drug use in a sample of 30 young adults with mild intellectual disability whose offending behaviour had resulted in involvement in the criminal justice system, with a matched comparison group of 30 non-offenders. Performance on an alcohol and other drug knowledge test was also compared. The results indicated that many individuals with mild intellectual disability regularly consumed alcohol and used illicit drugs. Furthermore, the data suggest a possible link between substance abuse and offending behaviour in this population. Individuals who had offended reported greater use of both legal and illicit drugs than their non-offending counterparts and many reported that they had been under the influence of alcohol or illicit drugs at the time of committing the offence that had resulted in their current placement within the criminal justice system. Although deficits in knowledge were apparent in both groups, the offenders demonstrated greater overall knowledge about alcohol and other drugs.

Mirror neuron dysfunction in autism spectrum disorders

Autism spectrum disorders (ASDs) are developmental conditions characterized by deficits in social interaction, verbal and nonverbal communication and obsessive/stereotyped patterns of behaviour. Although there is no reliable neurophysiological marker associated with ASDs, dysfunction of the parieto-frontal mirror neuron system has been suggested as a disturbance linked to the disorder. Mirror neurons (MNs) are visuomotor neurons which discharge both when performing and observing a goal directed action. Research suggests MNs may have a role in imitation, empathy, theory of mind and language. Although the research base is small, evidence from functional MRI, transcranial magnetic stimulation, and an electroencephalographic component called the mu rhythm suggests MNs are dysfunctional in subjects with ASD. These deficits are more pronounced when ASD subjects complete tasks with social relevance, or that are emotional in nature. Promising research has identified that interventions targeting MN related functions such as imitation can improve social functioning in ASDs. Boosting the function of MNs may improve the prognosis of ASDs, and contribute to diagnostic clarity.

Investigating driving behaviour of older drivers with mild cognitive impairment using a portable driving simulator

While there is a large body of research indicating that individuals with moderate to severe dementia are unfit to drive, relatively little is known about the driving performance of older drivers with mild cognitive impairment (MCI). The aim of the current study was to examine the driving performance of older drivers with MCI on approach to intersections, and to investigate how their healthy counterparts perform on the same driving tasks using a portable driving simulator. Fourteen drivers with MCI and 14 age-matched healthy older drivers (aged 65-87 years) completed a 10-min simulator drive in an urban environment. The simulator drive consisted of stop-sign controlled and signal-controlled intersections. Drivers were required to stop at the stop-sign controlled intersections and to decide whether or not to proceed through a critical light change at the signal-controlled intersections. The specific performance measures included; approach speed, number of brake applications on approach to the intersection (either excessive or minimal), failure to comply with stop signs, and slower braking response times on approach to a critical light change. MCI patients in our sample performed more poorly than controls across a number of variables. However, because the trends failed to reach statistical significance it will be important to replicate the study using a larger sample to qualify whether the results can be generalised to the broader population.

Stress, inflammation, and cellular vulnerability during early stages of affective disorders: biomarker strategies and opportunities for prevention and intervention

The mood disorder prodrome is conceptualized as a symptomatic, but not yet clinically diagnosable stage of an affective disorder. Although a growing area, more focused research is needed in the pediatric population to better characterize psychopathological symptoms and biological markers that can reliably identify this very early stage in the evolution of mood disorder pathology. Such information will facilitate early prevention and intervention, which has the potential to affect a person’s disease course. This review focuses on the prodromal characteristics, risk factors, and neurobiological mechanisms of mood disorders. In particular, we consider the influence of early-life stress, inflammation, and allostatic load in mediating neural mechanisms of neuroprogression. These inherently modifiable factors have known neuroadaptive and neurodegenerative implications, and consequently may provide useful biomarker targets. Identification of these factors early in the course of the disease will accordingly allow for the introduction of early interventions which augment an individual’s capacity for psychological resilience through maintenance of synaptic integrity and cellular resilience. A targeted and complementary approach to boosting both psychological and physiological resilience simultaneously during the prodromal stage of mood disorder pathology has the greatest promise for optimizing the neurodevelopmental potential of those individuals at risk of disabling mood disorders.

Effects of Comorbid ADHD With Learning Disabilities on Anxiety, Depression, and Aggression in Adults

Objective: ADHD and learning disabilities (LD) frequently coexist and there are indications that comorbidity may increase the risk of psychopathology. Method: The current study examined the gender distribution and frequency of comorbidity and its impact on the prevalence of symptoms of anxiety, depression, and aggression in a clinic sample of 80 adults with ADHD, aged 18 to 58 years. More individuals were diagnosed with ADHD+LD than ADHD only, with no difference in this distribution according to gender. Results: A factorial multivariate analysis of variance indicated that females with ADHD+LD displayed more cognitive depression than females with ADHD only and than males with ADHD+LD and ADHD only. However,individuals with ADHD only and individuals with ADHD+LD did not differ on overall anxiety, depression or aggression. Likewise, males and females did not differ on measures of psychopathology. Conclusion: This study lays the foundation for continued research into the characteristics and comorbidities of adults with ADHD. (J. of Att. Dis. 2009; 12(6) 525-531 )

Diabetes in people with an intellectual disability: a systematic review of prevalence, incidence and impact

To establish the prevalence and incidence of Type 1 and Type 2 diabetes in people with an intellectual and developmental disability and determine their impact on health and well‐being and to appraise the evidence available to inform good practice in diabetes management for people with intellectual and developmental disabilities.

The Efficacy of a Brief Behavioral Sleep Intervention in School-Aged Children With ADHD and Comorbid Autism Spectrum Disorder.

Objective: Sleep problems are common in children with autism spectrum disorders (ASD) and ADHD and impact adversely on child and parent well-being. The study evaluated the efficacy of a brief behavioral sleep intervention in children with comorbid ADHD–ASD. Method: A subsample of children with ADHD–ASD (n = 61; 5-13 years; 89% male) participating in the Sleeping Sound With ADHD study were included in the current investigation. The subsample comprised of 28 children randomized to the sleep intervention group, while 33 were randomized to usual clinical care. The intervention consisted of two clinical consultations and a follow-up phone call covering sleep hygiene and standardized behavioral strategies. Results: Children with ADHD–ASD who received the intervention had large improvements in sleep problems and moderate improvements in child behavioral functioning 3 and 6 months post-randomization. Conclusion: These findings suggest that a brief behavioral sleep intervention can improve sleep problems in children with ADHD–ASD.

Do we need both cognitive and behavioural components in interventions for depressed mood in people with mild intellectual disability

BACKGROUND A growing literature suggests that people with mild intellectual disability (ID) who have depressed mood may benefit from cognitive-behavioural interventions. There has been some speculation regarding the relative merit of the components of this approach. The aim of this study was to compare (i) cognitive strategies; (ii) behavioural strategies; and (iii) combined cognitive-behavioural (CB) strategies on depressed mood among a sample of 70 individuals with mild ID. METHODS Staff from three participating agencies received training in how to screen individuals with mild ID for depressive symptoms and risk factors for depression. Depressive symptoms and negative automatic thoughts were assessed prior to and at the conclusion of the intervention, and at 6-month follow-up. The interventions were run in groups by the same therapist. RESULTS A post-intervention reduction in depression scores was evident in participants of all three interventions, with no significant difference between groups. A significant reduction in negative automatic thoughts post-intervention was evident in the CB combination group and was maintained at follow-up. Examination of clinical effectiveness suggests some advantage of the CB combination in terms of improvement and highlights the possible short term impact of behavioural strategies in comparison with the longer-term potential of cognitive strategies. CONCLUSIONS The findings support the use of group cognitive-behavioural interventions for addressing symptoms of depression among people with ID. Further research is necessary to determine the effectiveness of components.