'I still remember': Increased categoric autobiographical memories in behavioural variant of frontotemporal dementia
Autobiographical memory is diminished in patients with behavioural variant of frontotemporal dementia (bvFTD), and research has focused on the hampered ability of patients to retrieve specific memories. In this study, we implemented a methodology seeking to provide a qualitative analysis of autobiographical specificity. We invited patients with bvFTD and control participants to retrieve autobiographical memories and we distinguished between specific, categoric, extended and semantic autobiographical retrieval. The analysis demonstrated that patients with bvFTD produced more categoric than specific, extended or semantic memories. Thus, despite the decreased ability to retrieve specific memories, an increased ability to produce categoric memories can be observed in patients with bvFTD. These results support a positive view according to which autobiographical retrieval in bvFTD is not solely characterized by over-generality, but also by increased retrieval of categoric memories. Categoric memories, albeit lacking uniqueness, nevertheless, involve retrieval of similar or related events upon which patients may draw knowledge related to their self-image and life story.
Resolving the problem of surface dyslexia in Italian through inflection of irregular verbs
Surface dyslexia and dysgraphia are considered diagnostic features of semantic variant primary progressive aphasia (svPPA) and are useful signs in English, a language whose attributes afford numerous opportunities to observe these phenomena. This, however, is not the case in many languages, including Italian, that have high transparency between orthography and phonology, making surface reading and spelling errors scarce. This creates a problem in applying the diagnostic recommendations for svPPA in such languages. Surface dyslexia and dysgraphia are examples of 'regularization' errors in which semantic knowledge loss leads to a failure to recognize exceptions that do not follow standard rules of pronunciation. Another form of regularization involves the incorrect inflection of irregular verbs using the rules that govern regular verbs. Unlike irregularly pronounced words, Italian, as with many languages, has numerous irregular verbs. The Italian Verb Inflection Test (IVIT) was developed to test the hypothesis that svPPA would regularize irregular verbs when inflecting them into two Italian past tenses. Results confirmed that people with svPPA made a significantly greater proportion of regularization errors compared to people with typical Alzheimer's disease or logopenic variant PPA. Without recourse to the other diagnostic features of PPA subgroups, the IVIT on its own could separate svPPA from these other two groups with 70% sensitivity and ~ 80% specificity. Regularization of irregular verb inflection offers a solution to the problem of applying the surface dyslexia/dysgraphia criterion for svPPA diagnosis in Italian.
Non-optimal cognitive offloading in schizophrenia in a prospective memory task: Influence of both metacognitive beliefs and cognitive effort avoidance
Cognitive offloading refers to the use of physical action and the external environment to simplify mental demand. One form of this-intention offloading-involves the use of external reminders to support delayed intentions. Both beliefs of poor memory ability and a preference to avoid cognitive effort lead to offloading intentions rather than using internal memory. Schizophrenia is a population with deficits in prospective memory and to overcome this difficulty, neuropsychological interventions can propose external aids such as reminders. However, it is unknown what motivates individuals with schizophrenia to spontaneously use reminders. Twenty-seven individuals with schizophrenia and twenty-seven non-clinical individuals were recruited to perform a prospective memory task, with two levels of difficulty, by deciding whether to use reminders or their internal memory. The proportion of reminder use, performance (hits and errors), subjective effort and metacognitive beliefs were recorded. The results show a non-optimal use of reminders in the schizophrenia group: this group used more reminders than the non-clinical group when the task was easy but did not increase reminder usage when the task became more difficult. Individuals with schizophrenia perceived the task to be more effortful than the non-clinical individuals in the easy task, but also had a high estimation of their memory ability. Reminder usage in schizophrenia is atypical and non-optimal. This may relate to effort and metacognition but the direct influence of these factors remains to be demonstrated. The overall results open perspectives on the neuropsychological treatment of prospective memory in this population.
Translation and validation of the abbreviated Prefrontal Symptoms Inventory (PSI-20): A tool for assessing prefrontal symptoms in English-speaking populations
This study introduces the translation and validation of the Prefrontal Symptoms Inventory (PSI) into English, aiming to provide an ecologically valid tool for assessing prefrontal symptoms in English-speaking populations in the United States. The prefrontal cortex (PFC) plays a crucial role in executive functions and other higher-order cognitive processes, with dysfunctions in this area associated with various cognitive, emotional and behavioural changes. Despite the existence of established tools like the Dysexecutive Questionnaire (DEX), the PSI addresses limitations found in the literature, presenting a novel ecologically valid tool for assessing prefrontal symptoms. The current study, involving 226 English-speaking participants, lays a foundational step for validating the PSI for use in a new population. Semi-confirmatory factorial analysis revealed a unidimensional structure, mirroring the Spanish version with robust fit indicators. Additionally, in assessing convergent validity, the abbreviated version (PSI-20) exhibited high correlations with DEX scores and moderate correlations with Psychological Stress Scale and General Health Questionnaire-12 scores. These findings align with previous reports, supporting the PSI-20's measurement of similar constructs related to prefrontal cortex activity and mental health components. The results of this study overall highlight the PSI's potential contribution to advancing prefrontal symptom evaluation in clinical and non-clinical settings.
Reducing confusion surrounding expert conceptions of Alzheimer's and dementia: A practical analysis
Biological, clinicobiological and clinical conceptions of Alzheimer's disease and related dementias are being promoted simultaneously to different practical ends. The co-existence of contemporary conceptions and the 'scary label' associated with older diagnostic criteria create the possibility of misunderstanding and harm. In this comment, we argue in favour of socio-ethical interventions targeted to health workers and the general public so as to lower the uncertainties introduced by contemporary diagnostic criteria and to articulate how they relate to established criteria.
Laterality in tactile working memory: The one-hand version of the Tactual Span
The Tactual Span assesses tactile working memory (WM) using both hands while applying forward and backward conditions. The study objectives were to validate a one-hand version of the Tactual Span and to evaluate WM laterality in the tactile modality. Of the 145 participants, 80 performed the Tactual Span with their right hand, and 65 performed it with their left hand. Moreover, all participants performed two span tasks in the visuo-spatial and auditory modalities, each encompassing forward and backward conditions. Results revealed adequate Cronbach's alpha values for each hand in both conditions of the Tactual Span, along with a positive correlation between forward and backward conditions in each hand. However, overall performance on the Tactual Span was poorer compared to performance on the Auditory and Visuo-spatial Spans. Furthermore, in the forward condition, there was a correlation between the Auditory Span and the Tactual Span, but only for the right hand. In the backward condition, the Auditory Span correlated with the Tactual Span in both hands. The findings indicate that there is no effect of hand laterality in tactile WM, showing the two hands are related to each other in their WM function. Additionally, the one-hand version of the Tactual Span is deemed useful for evaluating tactile WM and can therefore be used in empirical and clinical settings for neuropsychological assessment purposes.
How pain and body representations transform each other: A narrative review
Pain, as a multidimensional and subjective experience, intertwines with various aspects of body representation, involving sensory, affective and motivational components. This review explores the bidirectional relationship between pain and body representations, emphasizing the impact of the sense of ownership on pain perception, the transformative impact of pain on motor imagery, the effects associated with vicarious pain perception on body representations and the role of pain in the maintenance of body representations in specific clinical conditions. Literature indicates complex interactions between pain and body representations, with the sense of ownership inducing analgesic effects in some cases and hyperalgesia in others, contingent upon factors such as the appearance of the affected limb. Pain sensations inform the body on which actions might be executed without harm, and which are potentially dangerous. This information impacts on motor imagery too, showing reduced motor imagery and increased reaction times in tasks where motor imagery involves the painful body parts. Finally, contrary to the conventional view, according to which pain impairs body representation, evidence suggests that pain can serve as an informative somatosensory index, preserving or even enhancing the representation of the absent or affected body parts. This bidirectional relationship highlights the dynamic and multifaceted nature of the interplay between pain and body representations, offering insights into the adaptive nature of the central nervous system in response to perceived bodily states.
Body schema and body image as internal representations of the body, and their disorders. An historical review
Since the early 1900s, the terms body schema and body image denoted the internal representations of the body. Bonnier's (1905, Revue Neurologique, 13, 605) schema is a conscious spatial representation of the size, shape, and position of the body, and of body parts, whose dysfunction brings about aschématia, and hypo-, hyper-, and paraschématia. The two schemata of Head and Holmes (1911, Brain, 34, 102) are an unconscious plastic postural schema, for the maintenance of posture and balance and for the coding of the position of body parts, and a conscious superficial schema, for the localisation of somatosensory stimuli. Pick's (1922, Psychologische Forschung, 1, 303) body schema refers to a structural description of the body, including the position of body parts and their spatial relationships, defective in autotopagnosia. Schilder's (1935, The image and appearance of the human body) body image is a comprehensive construct, covering physiological, evolutional, neurological and neuropsychological, psychiatric and sociological aspects. Lhermitte's (1939, L'image de notre corps) image, based on the views of the abovementioned authors, is defective in bodily neuropsychological disorders. The two terms have been used interchangeably, to denote (hemi-)asomatognosia, anosognosia, autotopagnosia, depersonalisation, personal neglect, phantom and supernumerary limbs, somatoparaphrenia. Their properties have been summarized with general dichotomies: schema for action in space ("where" system), image for perception ("what" system), after primary sensory processing. While schema and image fractionated into multiple representations of aspects of the body, the two terms are still used to refer to some of these representations, and to their disorders.
The neuronal signature of surprised facial expression processing under different attentional focuses: A time-domain and time-frequency study
Previous studies have shown that high-arousal positive and negative facial expressions influence event-related potential (ERP) and time-frequency responses depending on attentional focuses. However, little is known about how relevant neural responses are influenced by surprised facial expressions, which are also high in arousal but ambiguous in valence. To address the issue, 38 participants were presented with surprised, happy, angry and neutral facial expressions. Attention was manipulated to focus on facial emotional attributes, facial non-emotional attributes, non-facial attributes, or was free to the participants. ERP results showed larger N170 responses to surprised compared to neutral facial expressions when attention focused on facial attributes and to surprised compared to angry and neutral facial expressions when attention focused on facial non-emotional attributes. Time-frequency analyses revealed reduced power of early occipital theta to surprised compared to happy and angry expressions when attention focused on facial emotions and to surprised compared to angry expressions when attention focused on non-facial stimuli. Parietal delta power was smaller for surprised facial expressions than for angry facial expressions when attention focused on facial emotions and for surprised facial expressions than for angry and neutral facial expressions when attention was directed to non-facial stimuli. These findings might suggest that neural responses to surprised facial expressions are modulated by attentional focus.
Effects of looming audio on transcranial magnetic stimulation-induced phosphene perception
Looming sounds are known to influence visual function in the brain, even as early as the primary visual cortex. However, despite evidence that looming sounds have a larger impact on cortical excitability than stationary sounds, the influence of varying looming strengths on visual ability remains unclear. Here, we aim to understand how these signals influence low-level visual function. Fourteen healthy undergraduate students participated. They were blindfolded and received transcranial magnetic stimulation (TMS) to the primary visual cortex following auditory stimulation with different strength looming sounds. Participants reported whether they perceived a phosphene, or an illusory visual percept, following TMS stimulation. We hypothesized that rates of phosphene activity would increase with increasing levels of looming strength. A linear mixed-effect model showed that phosphene activity was significantly higher at higher strength of looming (F(1, 69) = 5.33, p = .024) and at higher TMS pulse strength (F(1, 18) = 4.71, p = .043). However, there was also a significant interaction between looming strength and pulse strength (F(1, 69) = 4.33, p = .041). At lower levels of TMS strength, phosphene rate increased with looming strength, while at higher levels of TMS strength the effect was reversed. These results suggest a complex relationship between looming strength and cortical activity, potentially reflecting the mixed contribution of total auditory energy and the rate of changes. This work will enhance our ability to predict audiovisual interactions and may help improve auditory warning systems designed to capture visual attention.
Visual self-face and self-body recognition in a left-brain-damaged prosopagnosic patient
The present case study describes the patient N.G., who reported prosopagnosia along with difficulty in recognising herself in the mirror following a left-sided temporo-occipital hemispheric stroke. The neuropsychological and experimental investigation revealed only a mild form of apperceptive prosopagnosia, without visual agnosia, primarily caused by an impaired visual processing of face-parts and body parts but not of full faces. Emotional expressions did not modulate her face processing. On the other hand, N.G. showed a marked impairment of visual self-recognition, as assessed with visual matching-to-sample tasks, both at the level of body-part and face-part processing and at a full-face level, featured by a deficit in the perceptual discrimination of her own face and body, as compared to the others' face and body. N.G.'s lesion mapping showed damage to the left inferior occipito-temporal cortex, affecting the inferior occipital gyrus and compromising long-range connections between the occipital/temporo-occipital areas and the anterior fronto-temporal areas. Overall, the present case report documents that visual processing of the person's own face may be selectively compromised by a left-sided hemispheric lesion disconnecting extra-striate body- and face-selective visual areas to self-representation regions. Moreover, others' (full) face processing may be preserved, as compared with the impaired ability to discriminate others' body and face parts.
Memory problems in elderly people with traumatic brain injury
The aim of this study is to assess the effectiveness of various therapy methods in elderly individuals with traumatic brain injury (TBI), taking into account the degree of memory loss and the severity of the injury. The study was conducted in 2022 in Moscow, Russia, and Sofia, Bulgaria, involving six clinics. A total of 200 elderly patients with TBI participated in the study, with a mean age of 72 years. Patients were categorized into groups based on the degree of memory loss and severity of the injury. Standardized tests, including the Mini-Mental State Examination (MMSE), Clock Drawing Test, Digit Symbol Substitution Test, and Free, and Cued Selective Reminding Test, were used to assess cognitive functions. The Progressive Learning Test evaluated patients' ability to memorize and reproduce information over time. Groups receiving physical therapy and cognitive rehabilitation showed statistically significant improvement in cognitive functions compared to other therapy methods. Specifically, the mean score of the MMSE in these groups increased by 7 points (p < .001). Patients with more severe memory loss demonstrated more pronounced improvement in cognitive functions following the integrated therapy approach. The mean MMSE score increased by 10 points (p < .001), whereas in patients with milder memory loss, the growth was less significant (mean increase of 5 points, p < .05). Groups receiving physical therapy and cognitive rehabilitation consistently demonstrated significantly better results compared to speech therapy and psychological support throughout the study period.
From neuropsychology to embodied neuroscience: Introduction to the special issue on body representation and body transformations
Neural correlates of individual differences in moral identity and its positive moral function
Moral identity is an important moral variable which has positive moral functions, such as contributing to prosocial behaviours, reducing antisocial behaviours, and resisting the risk factors of antisocial behaviours. However, little is known about the neural correlates of moral identity and the neural basis of the effect of moral identity on the risk factors of antisocial behaviours, including moral disengagement. In this study, we explored these issues in 142 college students by estimating the regional homogeneity (ReHo) through resting-state functional magnetic resonance imaging (fMRI). The whole-brain correlation analyses found that higher internalized moral identity was correlated with higher ReHo in the precuneus. Furthermore, the ReHo in the precuneus was negatively correlated with moral disengagement, suggesting positive moral functions of the neural mechanisms of moral identity. These findings deepen our understanding of individual differences in moral identity and provide inspiration for the education of moral identity and the intervention for moral disengagement from the perspective of the brain.
Validity and reliability of the Mobile Toolbox Faces and Names memory test
Validation of the Mobile Toolbox Faces and Names associative memory test is presented. Ninety-two participants self-administered Faces and Names in-person; 956 self-administered Faces and Names remotely but took convergent measures in person; and 123 self-administered Faces and Names remotely twice, 14 days apart. Internal consistency (.76-.79) and test-retest reliability (ICC = .73) were acceptable. Convergent validity with WMS-IV Verbal Paired Associates was satisfactory (immediate .54; delayed .58). The findings suggest the remotely administered Faces and Names is a reliable instrument.
Right versus left temporal lobe semiology in dementia: Lessons from two cases with focal frontotemporal dementia syndromes
Focal atrophy of the left anterior temporal lobe has been associated with the semantic type of primary progressive aphasia evolving to semantic dementia. In contrast, focal atrophy of the right temporal lobe has more recently been described as a controverse entity reported as the right temporal variant of FTD. We describe two cases of FTD dementia syndromes: in Case 1, atrophy of the right temporal lobe led to significant behavioural impairment and difficulties in recognizing known people. In Case 2, atrophy of the left temporal lobe was associated with severe aggressive, ritualistic behaviour and aphasia.
Cost-effectiveness of neuropsychological rehabilitation for acquired brain injuries: Update of Stolwyk et al.'s (2019) review
Acquired brain injuries (ABI), resulting from stroke or traumatic brain injury, cause a range of neuropsychological impairments and many patients continue to experience neuropsychological deficits years after onset. The increasing average age of the population highlights the importance of effective management strategies for the consequences of ABI. Despite the well-documented impact of rehabilitation interventions, the cost-effectiveness of neuropsychological rehabilitation remains largely unknown. This study conducted a scoping review to update the findings of Stolwyk et al. (Neuropsychological Rehabilitation, 2021, 31, 316), focusing on the economic evaluations of neuropsychological rehabilitation for individuals with ABI. Following the PIO framework, PRISMA ScR guidelines, and systematic review reporting checklist, the review screened 1027 articles and included eight studies published between 2019 and 2024. The studies encompassed either language rehabilitation or general neuropsychological programs, including neuropsychological interventions. The economic analyses, including two cost-effectiveness, five cost-utility, and one cost-benefit study, mostly adhered to CHEERS guidelines, enhancing the transparency and methodological rigour of their reporting. These studies demonstrated varying degrees of cost-effectiveness for interventions targeting post-stroke language disorders and neuropsychological rehabilitation for ABI, with significant cost savings and health benefits observed, particularly for home-based rehabilitation interventions. The included studies suffered from a short time horizon, limiting the ability to capture the long-term economic impacts and effectiveness of the interventions. Future research should focus on longer-term follow-up data and include broader search strategies to enhance understanding and optimise health care interventions. A comprehensive implementation of these economic analyses is crucial for informing policymakers, enabling them to introduce rehabilitative interventions based on solid evidence.
Neuropsychology and Politics Collide in the 2024 US Presdiential Election: Pitfalls of attacks on age, language, and memory
Public perception of dementia has emerged as a key factor in the 2024 United States presidential election. The first televised presidential debate (27 June 2024) evoked a groundswell of concern about the neuropsychological health and political viability of President Joseph R. Biden, Jr. A rapid erosion of public support ensued, culminating in the collapse of the reelection campaign the following month. Political attacks on the cognitive fitness of world leaders create dissonance for clinical neuroscientists. We are ethically prohibited from remotely diagnosing public figures. Yet, we are also citizens with the right to feel and express personal concerns. In this commentary, I will address an often-uneasy relationship between politics and neuropsychology with a focus on the history and rationale for ethical guidelines such as the Goldwater Rule. I will also discuss lessons learned from recent events in the 2024 US election cycle about neurological health literacy (e.g. How is dementia diagnosed?) and broader impacts of age-based political attacks on global public health initiatives that target stigma reduction and improved early detection of dementia.
Prospective memory functions in traumatic brain injury: The role of neuropsychological deficits, metamemory and impaired self-awareness
A large body of evidence suggests that individuals with traumatic brain injury (TBI) have significant difficulties with prospective memory (PM), the memory for future intentions. However, the processes underlying this cognitive deficit remain unclear. This study aimed to gather further evidence regarding PM functions in TBI and clarify the role of neuropsychological deficits, metamemory, and mood disorders. We used a laboratory-based clinical measure, the Virtual Week, to examine PM function in 18 patients with TBI and 18 healthy control subjects. Measures of attention, processing speed, executive functions, episodic memory, and self-report questionnaires were also administered. In line with prior literature, our findings indicate that individuals with TBI had a consistent deficit compared to controls across all PM tasks. In previous studies, TBI patients had more severe impairment on time-based tasks; nevertheless, our results show that across all participants event-based tasks were easier to perform compared to time-based only when the retrospective memory demand was high. The patients were not only impaired on the prospective component of PM but also failed to recognise the content of their task (the retrospective component). Interestingly, the TBI group did not report higher levels of everyday memory problems, anxiety and depression compared to the control group. These measures also failed to correlate with PM and recognition memory performance. This study found that besides the neuropsychological deficits, a global impairment in PM functioning is present in individuals with TBI across various task types, tasks low and high in retrospective demands, and event versus time-based.
Subjective cognitive decline and objective cognitive performance in older adults: A systematic review of longitudinal and cross-sectional studies
Older adults with subjective cognitive decline (SCD) have a higher risk of developing future cognitive decline than those without SCD. However, the association between SCD and objective cognitive performance remains unclear. This PRISMA 2020-compliant systematic review aims to provide a qualitative assessment of the longitudinal and cross-sectional relationship between SCD and objective cognitive performance in different cognitive domains, in neuropsychologically healthy, community-dwelling older adults (average age of 55 or older). To identify pertinent studies, a comprehensive search was conducted from seven databases. The National Heart, Lung and Blood Institute Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies was used to assess the quality of included studies. Inclusion criteria were met by 167 studies, which were full-text and published between 1 January 1982 and 16 May 2023 (inclusive) in the languages of English, French, or Spanish and presenting data on objective cognitive performance in older adults with SCD. Overall, we found that SCD was associated with poorer objective cognitive performance on measures of global cognition and memory longitudinally compared to non-SCD status, but this association was inconsistent in cross-sectional studies. This association became stronger with the use of continuous measures of SCD as opposed to dichotomous measures. Additionally, results highlight the known lack of consistency in SCD assessment among studies and comparatively small number of longitudinal studies in SCD research.
Mind reading dysfunctions in patients with obstructive sleep apnoea: A neuropsychological approach
Obstructive sleep apnoea syndrome (OSAS) is a prevalent sleep-related breathing disorder that has been extensively studied for its effects on cognitive functions. However, little attention has been given to investigating Mind Reading (MR) skills in patients with OSAS. In this study, we employed a neuropsychological approach to thoroughly assess various facets of MR skills in patients with OSAS. Forty-two patients with untreated moderate or severe OSAS (AHI ≥15; 30 men, 12 women) and 16 healthy controls (7 men and 9 women), matched by age, were enrolled. To assess MR skills, we used: (i) The Story-based Empathy Task (SET), which includes three experimental conditions: identifying intentions (SET-IA), emotional states (SET-EA), and a control condition for inferring causality reactions (SET-CI); (ii) the Ekman 60 Faces Test (Ek60), which measures emotion recognition from facial expressions. Our findings revealed that patients with OSAS exhibit deficits in emotion-related MR skills, while their ability to make inferences about the cognitive states of social partners remains largely preserved. This finding corroborates previous evidence indicating that social cognition, particularly MR skills, may be one of the cognitive domains affected by OSAS. It emphasizes the significance of investigating social cognition and the relationship between MR skills and social functioning as a new and intriguing area of research in patients with OSAS.
Cognitive and affective theory of mind in young and elderly patients with multiple sclerosis
Theory of mind (ToM) deficits have been reported in persons with multiple sclerosis (pwMS). However, most studies have used pictures or written scenarios as stimuli without distinguishing between cognitive and affective ToM, and no studies have investigated older pwMS. We recruited 13 young healthy controls (HC), 14 young pwMS, 14 elderly HC and 15 elderly pwMS. ToM was measured using an adaptation of the Conversations and Insinuations task (Ouellet et al., J. Int. Neuropsychol. Soc., 16, 2010, 287). In this ecological video-based task, participants watch four 2-minute videos of social interactions, which are interrupted by multiple choice questions about either the emotional state (affective ToM) or the intention (cognitive ToM) of the characters. They also underwent a short neuropsychological battery including cognitive, executive and social cognition tasks and questionnaires. We observed a significant interaction between the ToM conditions and the groups regarding ToM performance. Elderly pwMS scored significantly lower than elderly HC and young pwMS in cognitive ToM, but not in affective ToM. They also showed the largest discrepancy between their cognitive and affective ToM. Young pwMS showed relatively preserved ToM in both conditions. Both cognitive and affective ToM correlated with global cognition and executive abilities, but not with social cognitive measures (emotion recognition, real-life empathy). This study suggests that decline in cognitive ToM might be accentuated by advancing age in pwMS. These impairments are most likely underlied by cognitive and executive difficulties, but not by core social cognitive impairments. Future studies should investigate the real-life impacts of ToM impairments in pwMS.
Direct access to specific autobiographical memories is lower in healthy middle-aged to older adult Apolipoprotein E ε4 carriers compared to non-carriers
Recent research suggests that the retrieval of autobiographical memories among cognitively healthy middle-aged and older adults is sensitive to the Apolipoprotein E ε4 (APOE4) allele, a genetic marker that increases the risk of Alzheimer's disease (AD) dementia. However, whether the APOE4-associated alteration in autobiographical memory retrieval encompasses rapid (i.e. direct retrieval) or iterative (i.e. generative retrieval) processes remains unclear. In the present study, 39 APOE4 carriers and 45 non-carriers (ages 60-80) who scored within normal limits on neuropsychological testing were cued to generate specific autobiographical events. We examined group differences in direct and generative retrieval and correlated direct and generative retrieval rates with performance on neuropsychological tests. Direct retrieval rates were lower in the APOE4 carriers compared to non-carriers. Episodic memory positively correlated with direct retrieval rates across the sample, though this relationship became non-significant when factoring in age and sex. There were no significant findings related to successful generative retrieval rates and its efficiency. In summary, compared to non-carriers, cognitively unimpaired middle-aged to older adult APOE4 carriers demonstrated greater difficulty, rapidly reconstructing specific autobiographical events without the support of semantic memory, suggesting that early autobiographical memory retrieval processes demonstrate vulnerability to AD-related risk factors.
Unlocking the potential of 'passive' modulation: How sensory stimulation shapes hand and face size
Knowledge of the body size is intricately tied to multisensory integration processes that rely on the dynamic interplay of top-down and bottom-up mechanisms. Recent years have seen the development of passive sensory stimulation protocols aimed at investigating the modulation of various cognitive functions, primarily inducing perceptual learning and behaviour change without the need for extensive training. Given that reductions in sensory input have been associated with alterations in body size perception, it is reasonable to hypothesize that increasing sensory information through passive sensory stimulation could similarly influence the perception of the size of body parts. The primary aim of this study was to investigate the potential modulatory effects of passive sensory stimulation on the perception of hand and face size in a group of young adults. Passive sensory stimulation effectively modulated the size representation of the stimulated hand, supporting the notion that access to somatosensory and proprioceptive information is prioritised for the hands but may not extend to the face. Increased somatosensory input resulted in a reduction of distortion, providing evidence for bottom-up modulation of size representation. Passive sensory stimulation can induce subjective changes in body size perception without the need for extensive training. This paradigm holds promise as a potential alternative for modulating distorted size representation in individuals with body representational deficits.
What I think she thinks about my paralysed body: Social inferences about disability-related content in anosognosia for hemiplegia
The neuropsychological disorder of anosognosia for hemiplegia (AHP) can offer unique insights into the neurocognitive processes of body consciousness and representation. Previous studies have found associations between selective social cognition deficits and anosognosia. In this study, we examined how such social cognition deficits may directly interact with representations of one's body as disabled in AHP. We used a modified set of previously validated Theory of Mind (ToM) stories to create disability-related content that was related to post-stroke paralysis and to investigate differences between right hemisphere damage patients with (n = 19) and without (n = 19) AHP. We expected AHP patients to perform worse than controls when trying to infer paralysis-related mental states in the paralysis-related ToM stories and explored whether such differences depended on the inference patients were asked to perform (e.g. self or other referent perspective-taking). Using an advanced structural neuroimaging technique, we expected selective social cognitive deficits to be associated with posterior parietal cortex lesions and deficits in self-referent perspective-taking in paralysis-related mentalising to be associated with frontoparietal disconnections. Group- and individual-level results revealed that AHP patients performed worse than HP controls when trying to infer paralysis-related mental states. Exploratory lesion analysis results revealed some of the hypothesised lesions, but also unexpected white matter disconnections in the posterior body and splenium of the corpus collosum associated with a self-referent perspective-taking in paralysis-related ToM stories. The study has implications for the multi-layered nature of body awareness, including abstract, social perspectives and beliefs about the body.
Using a nonparametric item response theory model to identify patterns of cognitive decline: The Mokken scale analysis
Cognitive decline, particularly in dementia, presents complex challenges in early detection and diagnosis. While Item Response Theory (IRT) has been instrumental in identifying patterns of cognitive impairment through psychometric tests, its parametric models often require large sample sizes and strict assumptions. This creates a need for more adaptable, less demanding analytical methods. This study aimed to evaluate the effectiveness of Mokken scale analysis (MSA), a nonparametric IRT model, in identifying hierarchical patterns of cognitive impairment from psychometric tests. Using data from 1164 adults over 60 years old, we applied MSA to the orientation subscale of ACE-III. Our analysis involved calculating scalability, monotone homogeneity, invariant item ordering (IIO) and response functions. The MSA effectively retrieved the hierarchical order of cognitive impairment patterns. Most items showed strong scalability and consistent patterns of cognitive performance. However, challenges with IIO were observed, particularly with items having adjacent difficulty parameters. The findings highlight MSA's potential as a practical alternative to parametric IRT models in cognitive impairment research. Its ability to provide valuable insights into patterns of cognitive deterioration, coupled with less stringent requirements, makes it a useful tool for clinicians and researchers.
The role of visuomotor synchrony on virtual full-body illusions in children and adults
The present study explored the effects of visuomotor synchrony in virtual reality during the embodiment of a full human avatar in children (aged 5-6 years) and adults. Participants viewed their virtual bodies from a first-person perspective while they moved the body during self-generated and structured movement. Embodiment was measured via questions and psychophysiological responses (skin conductance) to a virtual body-threat and during both movement conditions. Both children and adults had increased feelings of ownership and agency over a virtual body during synchronous visuomotor feedback (compared to asynchronous visuomotor feedback). Children had greater ownership compared to adults during synchronous movement but did not differ from adults on agency. There were no differences in SCRs (frequency or magnitude) between children and adults, between conditions (i.e., baseline or movement conditions) or visuomotor feedback. Collectively, the study highlights the importance of visuomotor synchrony for children's ratings of embodiment for a virtual avatar from at least 5 years old, and suggests adults and children are comparable in terms of psychophysiological arousal when moving (or receiving a threat to) a virtual body. This has important implications for our understanding of the development of embodied cognition and highlights the considerable promise of exploring visuomotor VR experiences in children.
The role of bodily experiences during pregnancy on mother and infant outcomes
Pregnancy is a transformative time for women and their bodies, and therefore thoughts and feelings and about one's own body and internal bodily sensations may understandably change during this period. Body satisfaction and interoception have been found to influence factors such as antenatal attachment (AA) and maternal mental health. However, mixed results in the literature suggest complex relationships between the bodily experience during pregnancy and outcomes, necessitating a broader investigative approach. We aim to examine the relationship between the pregnancy bodily experience and multiple mother-infant outcomes. It is hypothesised that poor bodily experiences during pregnancy will have negative impacts on these outcomes. Cross-sectional online survey data was collected from individuals at various gestations throughout pregnancy as part of a larger longitudinal study (N = 253, mean age = 32). We analysed validated measures of pregnancy body satisfaction, interoceptive sensibility, AA and mood, as well as intentions to breastfeed. Linear regressions were used to confirm findings from previous literature and a network analysis allowed for a more exploratory approach to understanding the importance of the bodily experience during pregnancy. Multiple regressions found low body satisfaction predicts higher levels of anxiety, depression and AA. A network analysis revealed relationships between body satisfaction and interoception during pregnancy and mother-infant outcomes, including depression and AA. Our results highlight the far-reaching effects of poor bodily experiences during pregnancy on a variety of outcomes. Understanding the impact of the pregnant bodily experience can help identify at-risk individuals and inform interventions.