Navigating internal consistencies: a case report on neuropsychological assessment of functional cognitive disorder

Functional cognitive disorder (FCD) is a subtype of functional neurological disorder (FND). FCD may include various cognitive symptoms, precipitants, and comorbid conditions (such as other FNDs, concussion, fatigue, or fibromyalgia). However, no widely available behavioral health interventions exist for FCD. The authors developed a therapist-guided and patient-led treatment for veterans and civilians with FCD. A well-known evidence-based treatment for functional seizures (an FCD-adjacent condition often with cognitive symptoms) was adapted to fit hypothesized mechanisms of FCD. The process used a health research format following the guidance for reporting intervention development studies. Key processes included determining the broad intervention framework, obtaining detailed FCD-specific content based on expert consensus, collecting evidence, developing theory, conducting target population-centered approaches, considering specialty subgroups, and gathering feedback from veteran and civilian stakeholders. The authors created a comprehensive 14-chapter manualized therapist-guided neurobehavioral therapy protocol for FCD symptoms independent of etiology, the Taking Control of Your Functional Cognitive Symptoms: Workbook. Initial feasibility, tolerability, and utility were assessed with two target-population stakeholders with FCD (one civilian patient and one veteran patient), with both reporting a Patient Global Impression of Change scale rating of 1 (indicating that their condition had very much improved). This promising new multimodality behavioral health intervention can be considered to be in stage 1 (i.e., intervention generation, refinement, modification, adaptation, and pilot testing). Further pilot testing is being conducted and will need to be followed by traditional efficacy testing (in stage 2).

IntroductionCurrently there is no standardized way to diagnose functional cognitive disorder (FCD) in clinical practice. We aimed to develop a bedside screening tool to differentiate between FCD and neurodegenerative causes...

Purpose Functional cognitive disorder (FCD) is an increasingly recognised condition which causes significant disability and distress. While it is known to be associated with depression, anxiety and reduced functioning, like other functional neurological disorders it may be marred by stigma. To date, little is known about the lived experience of those with FCD. Materials & methods As part of a randomised controlled feasibility trial of online group Acceptance and Commitment Therapy (ACT) for FCD we conducted in-depth qualitative interviews and utilised a thematic analysis approach to explore the challenges of living with FCD; how individuals cope with the symptoms; and their experiences of healthcare services. Results We recruited six women and three men, with a median age of 54. They described living with FCD which included experiences of loss of identity, altered role, feelings of confusion, frustration and low self-esteem, stigma, social isolation, and dismissal by healthcare services. Nevertheless, suffers strove to find strategies to ameliorate their symptoms. Conclusions FCD is a common and disabling condition which like other functional neurological symptoms leads to altered sense of self and unsatisfactory interactions with others, including healthcare professionals. The diagnosis should be made on positive grounds, clearly explained, and potential therapies investigated.

Patients frequently present to the memory clinic with self-reported cognitive symptoms that cannot be attributed to structural, toxic, or metabolic causes, and are out of keeping with their performance on neuropsychological assessment. This can be considered to be Functional (psychosomatic) Cognitive Disorder, which results in significant patient distress and often has a major impact on social functioning and employment. We performed a retrospective analysis of the Bristol ReMemBr group cognitive clinic database to ascertain the prevalence of Functional Cognitive Disorder, review the patient characteristics, and develop new guidelines for diagnosis and management. 196 patients were screened of whom 23 were diagnosed with Functional Cognitive Disorder; the oldest patient with this diagnosis was aged 60 years at symptom onset. When considering only those presenting below the age of 60 years (total no. held on database = 69), a third were diagnosed with Functional Cognitive Disorder. On neuropsychological testing, 47% had an atypical (invalid) pattern of results, or failed tests of performance validity. Of those with valid neuropsychological results, 80% scored in the normal range. Depression and anxiety were common but did not appear to be the primary cause of cognitive symptoms. Particular characteristics seen were excessively low self-rating of memory ability, and discrepancies between perceived and actual cognitive performance. The rate of unemployment was high, often due to the cognitive symptomatology. This is an important disorder to address, being common in working adults, and carrying a risk of misdiagnosis as early neurodegeneration, with subsequent inappropriate treatment and inclusion in clinical trials.

<h3>Objective</h3> The term “functional cognitive disorder” (FCD) has been proposed to describe a subjective experience of cognitive dysfunction in the absence of underlying brain pathology. Features of FCD include discrepancies between cognitive symptoms and objective performance, memory perfectionism, over-interpretation of attentional lapses and heightened self-monitoring for cognitive errors. Fibromyalgia and non-cognitive functional neurological disorders (FND) such as non-epileptic attacks (NEA) can be associated with subjective cognitive symptoms, sometimes referred to as “brain fog”. The relationship between archetypal FCD and cognitive symptoms in the context of fibromyalgia and FND is unclear. We conducted a systematic review of cognitive findings in fibromyalgia and FND in order to define their key neuropsychological hallmarks. Our hypothesis was that the cognitive profile associated with functional motor and pain syndromes (i.e. brain fogs) will be similar to that seen in isolated FCD. <h3>Method</h3> We performed a systematic review of studies evaluating cognition in fibromyalgia and FND. We identified 56 studies on fibromyalgia and 40 studies on FND. Study characteristics were highly heterogeneous. <h3>Results</h3> A high frequency of cognitive symptoms was described in fibromyalgia but no consistent neuropsychological deficits were seen. However, some authors found memory symptoms to correlate with attentional abnormalities (in particular tests of divided attention), and these to pain. In NEA problems with memory and attention were also reported. However, most studies comparing NEA with epilepsy did not report generalised neuropsychological differences. Discrepancies between cognitive symptoms and objective performance were rarely investigated, and evidence was inconsistent. Effort testing was rarely included in neuropsychological assessment, particularly in fibromyalgia. However, only a minor proportion of patients failed on effort testing. Notably, effort definition and assessment tools were highly variable. “Memory perfectionism” was not evaluated. <h3>Conclusion</h3> Both fibromyalgia and FND appear to show prominent cognitive symptoms. Regarding objective performance, reduced attentional reserve has been postulated to explain symptoms such as distractibility and attentional lapses. Evidence for discrepancies between cognitive symptoms and objective performance, and for poor effort on testing, remains contradictory. Overall, although limited, the data suggest that the neuropsychological mechanisms underlying ”brain fog” are similar to those in isolated FCD.

Objectives/AimsChronic pain is commonly reported as a comorbidity in patients with functional neurological disorder (FND) however the prevalence of FND in those presenting with chronic pain is unknown. We aimed...

Structural brain alterations and predictors of clinical improvement in functional cognitive disorder after concussion☆

Post-concussion syndrome (PCS) and Functional Neurological Disorder (FND), including Functional Cognitive Disorder (FCD), are two frequently encountered but diagnostically complex conditions. While PCS is conceptualized as a sequela of mild traumatic brain injury (mTBI), FND/FCD encompasses symptoms incompatible with recognized neurological disease, often arising in the absence of structural brain damage. Yet, both conditions exhibit considerable clinical overlap-particularly in the domains of cognitive dysfunction, emotional dysregulation, and symptom persistence despite negative investigations. This review critically examines the shared and divergent features of PCS and FND/FCD. We explore their respective epidemiology, diagnostic criteria, and risk factors-including personality traits and trauma exposure-as well as emerging insights from neuroimaging and biomarkers. We propose the "Functional Overlay Model" as a clinical tool for navigating diagnostic ambiguity in patients with persistent post-injury symptoms. PCS and FND/FCD frequently share features such as subjective cognitive complaints, fatigue, anxiety, and heightened somatic vigilance. High neuroticism, maladaptive coping, prior psychiatric history, and trauma exposure emerge as common risk factors. Neuroimaging studies show persistent network dysfunction in both PCS and FND, with overlapping disruption in fronto-limbic and default mode systems. The Functional Overlay Model helps to identify cases where functional symptomatology coexists with or replaces an initial organic insult-particularly in patients with incongruent symptoms and normal objective testing. PCS and FND/FCD should be conceptualized along a continuum of brain dysfunction, shaped by injury, psychology, and contextual factors. Early recognition of functional overlays and stratified psychological interventions may improve outcomes for patients with persistent, medically unexplained symptoms after head trauma. This review introduces the Functional Overlay Model as a novel framework to enhance diagnostic clarity and therapeutic planning in patients presenting with persistent post-injury symptoms.

Purpose of this reviewThis narrative review provides an overview of functional cognitive disorder (FCD) as a cognitive subtype within the functional neurological disorder (FND) spectrum. It addresses the conceptual challenges, diagnostic criteria, and epidemiology of FCD, emphasizing the need for standardization of internal inconsistency and clearer diagnostic boundaries to improve clinical assessment and research.Recent findingsFCD is characterized by persistent cognitive complaints disproportionate to objective performance, underpinned by metacognitive, attentional, and cognitive-behavioural dysfunction. Emerging evidence supports a predictive processing framework in which maladaptive top-down priors and attentional dysregulation perpetuate subjective cognitive deficits despite preserved or inconsistent objective cognitive performance. Diagnostic criteria and FCD checklists show promise, although challenges remain in standardizing neuropsychological assessments and integrating patient-reported experiences. Epidemiological data highlight the stability of FCD and its distinctiveness from neurodegenerative conditions, with a nonprogressive trajectory in most cases.Summary statementDefining and refining FCD through standardized criteria and mechanistic models is crucial for enhancing diagnostic accuracy, patient care, and research validity. Advancing our understanding of the pathophysiology of FCD within the FND framework will facilitate targeted interventions and improve trial cohort purity in neurodegenerative disease research. Future studies should focus on objective biomarkers and therapeutic strategies that address attentional and metacognitive dysfunction in FCD.

Functional Cognitive Disorder (FCD) is defined by persistent subjective cognitive complaints that are inconsistent with objective performance on neuropsychological testing. One leading hypothesis suggests that FCD may involve a dissociation between different forms of metacognition, particularly between global and local self-monitoring mechanisms. To quantitatively synthesize the evidence for global and local metacognitive performance in individuals with FCD through meta-analysis. We conducted a systematic review and meta-analysis of studies measuring metacognitive performance in FCD, including comparisons with healthy controls and mild cognitive impairment (MCI). Global metacognition was assessed using self-appraisal metrics, while local metacognition was measured using trial-by-trial confidence accuracy tools such as meta-d'/d'. Effect sizes (Cohen's d) were calculated and pooled using random-effects models. Three studies were included in the global metacognition analysis, revealing a large pooled effect size indicating impaired global metacognition in FCD (Cohen's d = - 1.07). One study assessed local metacognition and showed no impairment (Cohen's d = 0.00). This supports the proposed dissociation, with preserved local but disrupted global self-monitoring. Our findings provide meta-analytic evidence for a substantial deficit in global metacognitive insight in individuals with FCD, while local metacognitive abilities remain relatively intact. These results offer a mechanistic explanation for the discrepancy between subjective complaints and objective test performance in FCD. Interventions targeting global metacognitive appraisal may enhance clinical outcomes. Given the very small number of eligible studies, these findings should be interpreted cautiously and viewed as preliminary.

Functional cognitive disorder is common but underlying mechanisms remain poorly understood. Metacognition, an individual’s ability to reflect on and monitor cognitive processes, is likely to be relevant. Local metacognition refers to an ability to estimate confidence in cognitive performance on a moment-to-moment basis, whereas global metacognition refers to long-run self-evaluations of overall performance. Using a novel protocol comprising task-based measures and hierarchical Bayesian modelling, we compared local and global metacognitive performance in individuals with functional cognitive disorder. Eighteen participants with functional cognitive disorder (mean age = 49.2 years, 10 males) were recruited to this cross-sectional study. Participants completed computerized tasks that enabled local metacognitive efficiency for perception and memory to be measured using the hierarchical meta-d’ model within a signal detection theory framework. Participants also completed the Multifactorial Memory Questionnaire measuring global metacognition, and questionnaires measuring anxiety and depression. Estimates of local metacognitive efficiency were compared with those estimated from two control groups who had undergone comparable metacognitive tasks. Global metacognition scores were compared with the existing normative data. A hierarchical regression model was used to evaluate associations between global metacognition, depression and anxiety and local metacognitive efficiency, whilst simple linear regressions were used to evaluate whether affective symptomatology and local metacognitive confidence were associated with global metacognition. Participants with functional cognitive disorder had intact local metacognition for perception and memory when compared with controls, with the 95% highest density intervals for metacognitive efficiency overlapping with the two control groups in both cognitive domains. Functional cognitive disorder participants had significantly lower global metacognition scores compared with normative data; Multifactorial Memory Questionnaire-Ability subscale (t = 6.54, P < 0.0001) and Multifactorial Memory Questionnaire-Satisfaction subscale (t = 5.04, P < 0.0001). Mood scores, global metacognitive measures and metacognitive bias were not significantly associated with local metacognitive efficiency. Local metacognitive bias [β = −0.20 (SE = 0.09), q = 0.01] and higher depression scores as measured by the Patient Health Questionnaire-9 [β = −1.40 (SE = 2.56), q = 0.01] were associated with the lower global metacognition scores. We show that local metacognition is intact, whilst global metacognition is impaired, in functional cognitive disorder, suggesting a decoupling between the two metacognitive processes. In a Bayesian model, an aberrant prior (impaired global metacognition), may override bottom-up sensory input (intact local metacognition), giving rise to the subjective experience of abnormal cognitive processing. Future work should further investigate the interplay between local and global metacognition in functional cognitive disorder.

Functional Cognitive Disorder (FCD) is a common diagnosis at the memory clinic. FCD is characterised by significant self-reported cognitive symptoms in the absence of external evidence of cognitive dysfunction. A potential explanation for this is a deficit in metacognition, the process by which we internally judge our own abilities. Here we investigated differences in accuracy, confidence, and metacognition between people with FCD (N = 20), neurodegenerative mild cognitive impairment (nMCI; N = 14), and healthy controls (N = 23). The groups were assessed on forced choice memory and perceptual tasks, with trial by trial confidence ratings. FCD and nMCI participants showed lower accuracy on the memory task (means FCD 63.65%, nMCI 63.96%, HC 71.22%), with a significant difference between the FCD and HC groups after controlling for age and sex. There were no between-group differences in memory task confidence (means FCD 3.19, nMCI 3.59, HC 3.71). The FCD group showed greater confidence when longer time was allowed on the memory task. No between group differences in perceptual task accuracy (means FCD 63.97%, nMCI 64.50%, FCD 65.86%) or confidence (means FCD 3.71, nMCI 3.43, HC 3.88) were found. No differences in metacognitive efficacy emerged between the groups, either on the memory or perceptual task (Memory Meta-d’/d’:FCD 0.63, nMCI 0.94 HC 0.85; Perceptual Meta-d’,d’: FCD 0.50, nMCI 0.51, HC 0.72). Participants showed greater metacognitive efficacy on the memory task compared to the perceptual task. The difficulties experienced by people with FCD do not appear to be due to metacognitive deficits. Their performance was similar to people with nMCI over aspects of the memory tasks, which suggests that the primary issue may lie with memory encoding or retrieval, rather than with their judgement of performance accuracy.

Background: Functional Neurological Disorder (FND) encompasses conditions with neurological symptoms inconsistent with structural pathology, arising instead from complex interactions between psychological, biological, and social factors. Despite growing research, the etiological and risk factor landscape remains only partially understood, complicating diagnosis and treatment. Objective: This systematic review maps risk factors for major FND subtypes such as functional seizures (psychogenic non-epileptic seizures or PNES), functional cognitive disorder (FCD), functional movement disorders (FMD), functional weakness and sensory disturbances, functional visual symptoms, and functional gait abnormalities by categorizing predisposing, precipitating, and perpetuating influences. Methods: A systematic search of PubMed, PsycINFO, Scopus, and Web of Science initially identified 245 records. After removal of 64 duplicates, 181 studies were screened by title and abstract. Of these, 96 full texts were examined in detail, and finally 23 studies met the predefined inclusion criteria. Data were extracted and analyzed thematically within a biopsychosocial framework, with results summarized in subtype-specific profiles. Results: Childhood adversity, especially emotional, physical, or sexual abuse, emerged as a robust and consistent predisposing factor across PNES cohorts. Psychiatric history (notably anxiety, depression, and PTSD), neurodevelopmental traits (more frequent in FCD), and personality patterns such as alexithymia and somatization also contributed to vulnerability. Precipitating influences included acute psychological stress, intrapersonal conflict, or concurrent medical illness. Perpetuating factors comprise maladaptive illness beliefs, avoidance behaviors, insufficient explanation or validation by healthcare providers, and secondary gains related to disability. While several risk factors were shared across subtypes, others appeared subtype-specific (trauma was especially associated with PNES, whereas neurodevelopmental traits were more characteristic of FCD). Conclusions: FND arises from a dynamic interplay of predisposing, precipitating, and perpetuating factors, with both shared and subtype-specific influences. Recognizing this heterogeneity can enhance diagnostic precision, guide tailored intervention, and inform future research into the neurobiological and psychosocial mechanisms underlying FND.

Memory complaints are common in elderly and have various etiologies, including functional cognitive disorder (FCD). Diagnosis of FCD is supported by clinical evidence of incongruity with a neurodegenerative disorder and/or evidence of internal inconsistency - the ability to perform a task well at certain times, but with impaired ability at other times. The prevalence of features suggesting FCD in organic disorders is unclear. We assessed the presence of clinical features of internal inconsistency and other possible discriminators of FCD from organic causes in patients with mild cognitive impairment (MCI) and subjective cognitive impairment (SCI). Patients attending our tertiary memory clinic in a period of one year with SCI or MCI were included. Exclusion criteria were toxic or metabolic causes of cognitive decline, major psychiatric disorders, co-morbid neurological conditions that could affect cognition, and uncertainty of diagnosis of organic disorder or FCD. Medical records were reviewed for evidence of internal inconsistency and other suggested discriminators between functional and organic etiology. Demographic, cognitive and clinical data were compared between groups. We evaluated 39 patients with FCD and 57 with organic disorders. MCI was more common in patients with organic disorders. However, most patients with FCD also had MCI. Patients with FCD were younger and performed better on cognitive assessments, but with significant overlap between groups (Table 1). While patients with FCD more commonly attended the appointment alone and reported greater concern about their symptoms than their supporters, these features were unspecific (Table 2). Patients with FCD reported symptoms that could represent normal experiences and provided detailed descriptions of memory lapses more commonly. While less sensitive, memory perfectionism and symptoms occurring only in specific situations were highly specific for FCD. Differentiation between functional and organic cognitive disorders based on history and examination can be challenging. Features suggesting internal inconsistency and incongruity with neurodegeneration may also appear in organic causes of SCI and MCI. Their varying specificity and sensitivity for FCD need to be taken into account when considering the diagnosis. Improving the identification of FCD could in turn improve identification of patients with prodromal neurodegeneration.

We previously hypothesized that functional cognitive disorder is characterized by heightened subjective mental effort, exhausted attentional reserve and metacognitive failure. To test this hypothesis, we administered a Stroop colour-word task in which attentional demand was varied by task difficulty (congruent versus incongruent cues) and the presence of a secondary auditory stimulus (passive or active listening to an oddball-type paradigm). We measured subjective mental effort, objective performance (reaction times and accuracy), metacognition and EEG-based biomarkers of mental workload. We tested 19 functional cognitive disorder patients and 23 healthy controls. Patients reported higher levels of depression, anxiety, fatigue, pain, sleep disruption, dissociation and obsessiveness. They rated their memory as significantly poorer than healthy controls; however, accuracy did not differ between groups in any condition. In contrast to healthy controls, patients rated their performance as poorer on the congruent Stroop task with background noise compared to silent conditions. Functional cognitive disorder was consistently associated with slower reaction times but this was not exacerbated by increased attentional demand. Patients but not healthy controls reported greater mental workload in noisy conditions but EEG biomarkers were similar between groups, regardless of task difficulty. Functional cognitive disorder has significant syndromic overlap with mood disorders and chronic fatigue and pain. It is associated with global metacognitive failure whereas local (task-specific) metacognition is only selectively impaired. Patients were slower than healthy controls, which might contribute to the 'brain fog' reported in this condition. Although subjective mental effort was increased in noisy conditions, we found no evidence of attentional exhaustion in functional cognitive disorder. Our results indicate that functional cognitive disorder is a multisystem condition affecting reaction time, subjective mental effort and global metacognition.