Functional Neurological Disorders (FNDs) affect motor or sensory functions without a detectable underlying disease. FNDs encompass a range of presentations including non-epileptic seizures, cognitive changes, weakness, and sensory symptoms. The prevalence of FND as a diagnosis is increasing rapidly. Following our clinical observations of a high prevalence of Attention-Deficit Hyperactivity Disorder (ADHD) in people referred with a previous diagnosis of FND to our tertiary Neuropsychiatry pilot service in Derbyshire, we conducted an integrative literature review with the aim to investigate the prevalence of ADHD in people diagnosed with FND.

We conducted an integrative literature review using a systematic approach. A literature search was performed on two databases, PubMed and ScienceDirect. The keywords ‘Functional Neurological Disorder’, ‘Attention-Deficit Hyperactivity Disorder’, ‘Non-Epileptic Seizures’, ‘Functional’ were used. Databases were searched for initial search on 31 November 2023 and the search was repeated on 31 January 2024. Only articles in English language were included. Studies were eligible if reporting the prevalence of ADHD in FND populations. Studies involving adults and children were included. A further search was conducted on reference lists from the selected articles.

Database searches on PubMed and ScienceDirect had 298 and 11,837 results, respectively. Only seven studies were identified that explored the prevalence of ADHD in individuals diagnosed with a FND and were included. In the adult population an association between a FND diagnosis, and ADHD traits identified on screening, or a final ADHD diagnosis was identified. The findings also demonstrate an increased incidence of comorbid ADHD and FND with the presence of another co-existing neurodevelopmental disorder such as Autism Spectrum Disorder. Furthermore, results indicated that the prevalence of an ADHD diagnosis in children with a FND was higher compared with adults. The literature suggests that, in both adults and children with FND-related functional seizures there is an increased prevalence of comorbid ADHD.

In conclusion, the findings from this review demonstrate a lack of evidence looking into the prevalence of Attention-Deficit Hyperactivity Disorder in complex presentations being labelled as Functional Neurological Disorder. However, the existing literature indicates there is an association between FND and ADHD. These findings highlight the importance of considering potential ADHD comorbidity in the assessment and management of FND, potentially informing targeted treatment approaches for affected individuals. Further research could explore the efficacy of ADHD medication and similar dopamine modulating molecules in treating sub-cohort of people with FND.

Neuropsychiatry, being at the interface between Neurology and Psychiatry, can fulfil the unmet needs of a cohort of people with complex presentations including psychiatry symptoms associated with neurological diseases and atypical psychiatry presentations with possible underlying aberrant brain processes. However, the development and provision of Neuropsychiatry services have lagged behind in the United Kingdom and some parts of the world, at the cost of ongoing symptom burden and reduced quality of life for vulnerable groups of patients. We set up a tertiary pilot service of Neuropsychiatry in Derbyshire from March 2022 and have been successfully operating both outpatient Neuropsychiatry clinics as well as inreach on to psychiatric wards. We set out to evaluate our service and explore the challenges and outcomes associated with our service development.

A mixed methods evaluation was completed, and the data were extracted from patient records and assessments. Feedback responses were obtained from referring clinicians and service users utilising structured feedback forms for each group. A thematic analysis approach was completed for qualitative responses. More than 140 patients have already been assessed by our Neuropsychiatry service to date, out of which we completed an initial analysis of records of 70 patients referred between March 2022 and February 2023. We further revisited the challenges (lack of resources including clinic space, admin and dedicated electronic medical records (EMR) section).

67% of referrals were from Neurology services with Functional Neurological Disorder (FND) predominating. 74% of patients referred had more than one diagnosis/symptom cluster. Patients reported significant benefits and overall positive experiences from the service. One patient reported, “After 3 years I finally not only have answers to my symptoms but also an explanation as to why. Without this service, I believe I would be still struggling.” Similar positive feedback was obtained from referring clinicians.

Our results demonstrate that a successful tertiary Neuropsychiatry service can be established and run even under challenging circumstances including lack of resources. Our service now has a dedicated clinic running every week, a dedicated EMR section and we are currently in the process of submitting business plans towards sustainable commissioning. Furthermore, our service has been instrumental in reducing the length of inpatient stay, facilitating early discharges, diagnosing and treating reversible conditions that mimicked primary psychiatric issues, as well as improving the quality of life of a vulnerable cohort of people previously diagnosed with complex conditions such as FND and personality disorders.

FND can be considered as an umbrella term that includes range of motor and sensory system dysfunctions with genuine symptoms including paralysis, tremors, sensory disturbance, speech disturbance and seizure. Functional seizures usually termed as Non-Epileptic attack disorder (NEAD) can result in profound persisting disability. Brief bouts of unprovoked and uncontrollable laughter, spontaneous in origin, combined with facial contraction in the form of smile, is termed as ‘gelastic seizures’. Modafinil is a dopamine modulating molecule for which evidence is accumulating towards its cognitive enhancement role in multiple domains. Furthermore, it has been shown to promote hippocampal neurogenesis and synaptic plasticity in pre-clinical studies. We report a case of FND in which pharmacological (Modafinil) and non-pharmacological interventions (Brain retraining) resulted in resolution of symptoms of probable gelastic episodes.

A 50-year-old lady who was referred by consultant neurologist to our Neuropsychiatry pilot service with episodes of uncontrollable laughing, singing, screaming and suffering from staggering and imbalance. Following these episodes, patient described sleeping for hours to days with fatigue. Her husband first noticed low mood 12 years ago during post-natal period. Treatment with fluoxetine reportedly contributed to ‘cyclical highs and mood variations’. One year later, her ‘gelastic episodes’ started and continued to occur every 2 or 3 months and they were brought on by a range of factors including tiredness, menstrual periods and stress. Patient also reported atypical cognitive deficits such as ‘losing vocabulary’ and ‘stuck every couple of seconds’. Furthermore, detailed history confirmed possible traits of attention deficit and hyperactive thinking since her childhood.

Following a comprehensive assessment, the role of the brain in the manifestation of her symptoms was discussed and agreed upon. Strategies based on Cognitive Behaviour Therapy principles such as active distraction, brain retraining, engaging in therapeutic activities and expressive writing were discussed and agreed upon. Following detailed risk-benefit analysis, modafinil was initiated at 200 mg dose in the morning. Patient made a remarkable recovery nearly back to her baseline with resolution of her gelastic episodes and thus improvement in her mental state. She continues to be stable in the community.

This case highlights the importance of recognising and treating cluster of symptoms which might belong to the impulsive-compulsive spectrum. This further emphasises the role of dopamine-modulating agents such as modafinil along with brain-retraining strategies.

Traditional antipsychotic treatment improves positive symptoms in schizophrenia but has little impact on negative and cognitive symptoms. TMS is a non-invasive neuromodulation technique which has been suggested to impact negative and cognitive symptoms of schizophrenia. This systematic review critically appraised the research evaluating the effect of TMS on negative and cognitive symptoms of schizophrenia. Furthermore, we carried out a meta-analysis of randomised controlled trials of the effect of TMS on negative symptoms in schizophrenia.

Systematic review was carried out according to PRISMA guidelines. Cochrane Library, Ovid Medline, Science Direct and PubMed databases were searched for relevant studies using the search terms: “transcranial magnetic stimulation” OR “TMS” OR “repetitive transcranial magnetic stimulation” OR “r-TMS” OR “theta burst stimulation” OR “TBS” AND “negative symptoms” OR “cognitive dysfunction” OR “cognitive impairment” AND “schizophrenia” OR “psychosis”. Only randomised controlled trials evaluating the effect of TMS (rTMS or iTBS, intermittent theta burst) on negative and/or cognitive symptoms in schizophrenia were selected. Thirty-three studies were included in the systematic review. The Standardised mean difference (SMD) with 95% confidence interval (CI) was calculated for each study and pooled across studies using an inverse variance random effect model.

Sixteen studies demonstrated significant improvement in negative symptoms with a superior effect of TMS compared with sham intervention. Eight studies showed improvement in certain domains of cognition and one study showed a delayed effect on negative symptoms. Studies which showed positive effects on negative symptoms have used similar TMS parameters such as 10 Hz over L-DLPFC (Left dorsolateral prefrontal cortex) except for a few studies. Ten studies reported negative results for negative and/or cognitive symptoms, TMS parameters and duration of treatment used varied among these studies. Overall, SMD for SANS (Scale for Assessment of Negative Symptoms) was 0.89 (95%CI: 0.46–1.32, P < 0.00001) and for PANSS-N (Positive and Negative Syndrome scale-negative) was 0.67 (95%CI: 0.22–1.12, P < 0.00001), both in favour of TMS. The heterogeneity of the included studies was high, I2- 85% for SANS and 92% for the PANSS-N subscale with a small to moderate risk of publication bias.

High-frequency rTMS is more effective than sham in improving negative and cognitive symptoms in schizophrenia. Our results suggest the need for well-designed randomised controlled trials with larger sample sizes and standard harmonised cognitive assessments to assess the effect of TMS on negative and cognitive symptoms to provide sufficient evidence for inclusion in routine clinical practice.