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Journal of Neuropsychology Sep 2023The hub-and-spoke model of semantic cognition proposes that conceptual representations in a heteromodal 'hub' interact with and emerge from modality-specific features or...
The hub-and-spoke model of semantic cognition proposes that conceptual representations in a heteromodal 'hub' interact with and emerge from modality-specific features or 'spokes', including valence (whether a concept is positive or negative), along with visual and auditory features. As a result, valence congruency might facilitate our ability to link words conceptually. Semantic relatedness may similarly affect explicit judgements about valence. Moreover, conflict between meaning and valence may recruit semantic control processes. Here we tested these predictions using two-alternative forced-choice tasks, in which participants matched a probe word to one of two possible target words, based on either global meaning or valence. Experiment 1 examined timed responses in healthy young adults, while Experiment 2 examined decision accuracy in semantic aphasia patients with impaired controlled semantic retrieval following left hemisphere stroke. Across both experiments, semantically related targets facilitated valence matching, while related distractors impaired performance. Valence congruency was also found to facilitate semantic decision-making. People with semantic aphasia showed impaired valence matching and had particular difficulty when semantically related distractors were presented, suggesting that the selective retrieval of valence information relies on semantic control processes. Taken together, the results are consistent with the hypothesis that automatic access to the global meaning of written words affects the processing of valence, and that the valence of words is also retrieved even when this feature is task-irrelevant, affecting the efficiency of global semantic judgements.
Topics: Young Adult; Humans; Semantics; Aphasia; Stroke; Cognition; Judgment
PubMed: 37010272
DOI: 10.1111/jnp.12312 -
Neuropsychologia Jun 2018Motor conversion disorder (CD) entails genuine disturbances in the subjective experience of patients who maintain they are unable to perform a motor function, despite...
Motor conversion disorder (CD) entails genuine disturbances in the subjective experience of patients who maintain they are unable to perform a motor function, despite lack of apparent neurological damage. Abilities by which individuals assess their own capacities during performance in a task are called metacognitive, and distinctive impairment of such abilities is observed in several disorders of self-awareness such as blindsight and anosognosia. In CD, previous research has focused on the recruitment of motor and emotional brain systems, generally linking symptoms to altered limbic-motor interactions; however, metacognitive function has not been studied to our knowledge. Here we tested ten CD patients and ten age-gender matched controls during a visually-guided motor paradigm, previously employed in healthy controls (HC), allowing us to probe for motor awareness and metacognition. Participants had to draw straight trajectories towards a visual target while, unbeknownst to them, deviations were occasionally introduced in the reaching trajectory seen on the screen. Participants then reported both awareness of deviations and confidence in their response. Activity in premotor and cingulate cortex distinguished between conscious and unconscious movement corrections in controls better than patients. Critically, whereas controls engaged the left superior precuneus and middle temporal region during confidence judgments, CD patients recruited bilateral parahippocampal and amygdalo-hippocampal regions instead. These results reveal that distinct brain regions subserve metacognitive monitoring for HC and CD, pointing to different mechanisms and sources of information used to monitor and form confidence judgments of motor performance. While brain systems involved in sensory-motor integration and vision are more engaged in controls, CD patients may preferentially rely on memory and contextual associative processing, possibly accounting for how affect and memories can imbue current motor experience in these patients.
Topics: Adult; Analysis of Variance; Brain Mapping; Conversion Disorder; Female; Humans; Image Processing, Computer-Assisted; Judgment; Magnetic Resonance Imaging; Male; Metacognition; Movement; Oxygen; Prefrontal Cortex; Psychomotor Performance; Young Adult
PubMed: 29698734
DOI: 10.1016/j.neuropsychologia.2018.04.018 -
Psychiatry Research. Neuroimaging Oct 2019Judgments about another person's visual perspective are impaired when the self-perspective is inconsistent with the other-perspective. This is a robust finding in...
Judgments about another person's visual perspective are impaired when the self-perspective is inconsistent with the other-perspective. This is a robust finding in healthy samples as well as in schizophrenia (SZ). Studies show evidence for the existence of a reverse effect, where an inconsistent other-perspective impairs the self-perspective. Such spontaneous perspective taking processes are not yet explored in SZ. In the current fMRI experiment, 24 healthy and 24 schizophrenic participants performed a visual perspective taking task in the scanner. Either a social or a non-social stimulus was presented and their visual perspectives were consistent or inconsistent with the self-perspective of the participant. We replicated previous findings showing that healthy participants show increased reaction times when the human avatar's perspective is inconsistent to the self-perspective. Patients with SZ, however, did not show this effect, neither in the social nor in the non-social condition. BOLD responses revealed similar patterns in occipital areas and group differences were identified in the middle occipital gyrus. These findings suggest that patients with SZ are less likely to spontaneously compute the visual perspectives of others.
Topics: Adult; Humans; Judgment; Magnetic Resonance Imaging; Male; Photic Stimulation; Reaction Time; Schizophrenia; Schizophrenic Psychology; Visual Perception; Young Adult
PubMed: 31472416
DOI: 10.1016/j.pscychresns.2019.08.007 -
Journal of Alzheimer's Disease : JAD 2022Previous research finds a range of numbers impairments in Parkinsonian syndromes (PS), but has largely focused on how visuospatial impairments impact deficits in basic...
BACKGROUND
Previous research finds a range of numbers impairments in Parkinsonian syndromes (PS), but has largely focused on how visuospatial impairments impact deficits in basic numerical processes (e.g., magnitude judgments, chunking). Differentiation between these basic functions and more complex numerical processes often utilized in everyday tasks may help elucidate neurocognitive and neuroanatomic bases of numbers deficits in PS.
OBJECTIVE
To test neurocognitive and neuroanatomic correlates of complex numerical processing in PS, we assessed number abilities, neuropsychological performance, and cortical thickness in progressive supranuclear palsy (PSP) and Lewy body spectrum disorders (LBSD).
METHODS
Fifty-six patients (LBSD = 35; PSP = 21) completed a Numbers Battery, including basic and complex numerical tasks. The Mini-Mental State Exam (MMSE), letter fluency (LF), and Judgment of Line Orientation (JOLO) assessed global, executive, and visuospatial functioning respectively. Mann-Whitney U tests compared neuropsychological testing and rank-transformed analysis of covariance (ANCOVA) compared numbers performance between groups while adjusting for demographic variables. Spearman's and partial correlations related numbers performance to neuropsychological tasks. Neuroimaging assessed cortical thickness in disease groups and demographically-matched healthy controls.
RESULTS
PSP had worse complex numbers performance than LBSD (F = 6.06, p = 0.02) but similar basic numbers performance (F = 0.38, p > 0.1), covarying for MMSE and sex. Across syndromes, impaired complex numbers performance was linked to poor LF (rho = 0.34, p = 0.01) but not JOLO (rho = 0.23, p > 0.05). Imaging revealed significant frontal atrophy in PSP compared to controls, which was associated with worse LF and complex numbers performance.
CONCLUSION
PSP demonstrated selective impairments in complex numbers processing compared to LBSD. This complex numerical deficit may relate to executive dysfunction and frontal atrophy.
Topics: Atrophy; Cognitive Dysfunction; Humans; Multiple System Atrophy; Neuropsychological Tests; Parkinsonian Disorders; Supranuclear Palsy, Progressive
PubMed: 35811515
DOI: 10.3233/JAD-215327 -
Addictive Behaviors Sep 2022Metacognitive monitoring refers to the process in which an individual analyzes their own mental state, then monitors and adjusts cognitive activities to achieve a...
BACKGROUND AND OBJECTIVE
Metacognitive monitoring refers to the process in which an individual analyzes their own mental state, then monitors and adjusts cognitive activities to achieve a predetermined goal. Recent research has suggested a strong link between metacognition and drug cravings. Conversely, few studies on the impact of metacognitive monitoring on methamphetamine (MA) cravings exist. Thus, this study investigated whether drug cravings would impair MA abusers' metacognitive monitoring and explored the prediction effects of drug cravings.
METHOD
Seventy MA abusers from the Zhejiang Compulsory Isolation Drug Rehabilitation Center and 65 non-users from the Wenzhou Medical University were recruited for this experimental study. The judgment of learning (JOL) paradigm was used to examine metacognitive monitoring, and cue-induced pictures were used to induce MA abusers' drug cravings. Analysis of covariance (ANCOVA), partial correlation, and regression analysis were performed.
RESULTS
Compared with non-users, MA abusers had significantly poorer metacognitive monitoring and tended to overestimate their performance. Furthermore, there was a significant correlation between the accuracy of JOLs and drug cravings, which indicated that metacognitive monitoring was weakened by drug cravings with higher cravings imposing more severe impacts. In addition, the regression analysis suggested that drug cravings can predict metacognitive monitoring.
Topics: Craving; Humans; Judgment; Learning; Metacognition; Methamphetamine
PubMed: 35584984
DOI: 10.1016/j.addbeh.2022.107341 -
Psychonomic Bulletin & Review Aug 2020Theories of semantic memory based on neuropsychological findings have posited a distinction between stored semantic representations and the mechanisms used to access and... (Review)
Review
Theories of semantic memory based on neuropsychological findings have posited a distinction between stored semantic representations and the mechanisms used to access and manipulate them (e.g., Lambon Ralph, Jefferies, Patterson, & Rogers, 2017; Warrington & Cipolotti, 1996). The most recent instantiation of this view, the controlled semantic cognition theory (Lambon Ralph et al., 2017), is supported by findings suggesting that multimodal (i.e., both verbal and nonverbal) semantic deficits may result from qualitatively different impairments: on the one hand, damage to a semantic access mechanism related to executive control, which is observed in semantic aphasia (SA), and on the other, damage to semantic representations, which is observed in semantic dementia (SD) (Jefferies & Lambon Ralph, 2006). In this study we compared SA and SD patients on several phenomena previously used to support these distinctions. Contrary to the prior results, we found that (1) overall, cross-task consistency was equivalent for the two groups; (2) neither patient group showed consistency driven by item identity across different semantic tasks; (3) correlations among task performance were not obviously driven by the semantic control demands of different tasks; (4) both groups showed executive function deficits; and (5) both groups showed strong effects of distractor interference in a synonym judgment task. Furthermore, we investigated the components of executive ability that could underlie semantic control deficits by correlating performance on updating, shifting, and inhibition tasks with performance on tasks testing semantic abilities. We found that updating was related to semantic processing generally, whereas shifting and inhibition were not. These results also suggest that complex executive function tasks relate to semantic tasks through their shared relationship with language abilities. Overall, evidence from SA and SD patients does not differentiate representations and access mechanisms in the semantic system, as has previously been suggested. Implications for the storage-access distinction are discussed.
Topics: Aphasia; Comprehension; Executive Function; Frontotemporal Dementia; Humans; Judgment; Memory; Neuropsychological Tests; Psychological Theory; Semantics; Stroke
PubMed: 31993976
DOI: 10.3758/s13423-019-01706-6 -
Expert Review of Neurotherapeutics Jul 2022The main purpose of this manuscript is to critically review the Multisensory Integration (MI) training programs applied to older adults, their characteristics, target... (Review)
Review
INTRODUCTION
The main purpose of this manuscript is to critically review the Multisensory Integration (MI) training programs applied to older adults, their characteristics, target sensory systems, efficacy, assessment methods, and results. We also intend to propose an integrated framework to support combined interventions of neurocognitive and sensory training.
AREAS COVERED
A critical review was conducted covering the most relevant literature on the MI training programs applied to older adults. Two MI training programs applied to cognitively healthy older adults were found: (a) audio-visual temporal discrimination training and (b) simultaneity judgment training. Both led to the improvement of the MI between pre- and post-training. However, only the audio-visual temporal discrimination training led to the generalization of the improvements to another MI task.
EXPERT OPINION
Considering the relationship between sensory and cognitive functioning, this review supports the potential advantages of combining MI with neurocognitive training in the rehabilitation of older adults. We suggested that this can be achieved within the framework of Branched Programmed Neurocognitive Training (BPNT). Criteria for deciding the most suitable multisensory intervention, that is, MI or Multisensory Stimulation, and general guidelines for the development of MI intervention protocols with older adults with or without cognitive impairment are provided.
Topics: Aged; Cognition; Cognitive Dysfunction; Humans; Judgment; Visual Perception
PubMed: 35722763
DOI: 10.1080/14737175.2022.2092401 -
Scientific Reports Oct 2019Monitoring is a complex multidimensional neurocognitive phenomenon. Patients with fronto-insular stroke (FIS), behavioural variant frontotemporal dementia (bvFTD) and...
Monitoring is a complex multidimensional neurocognitive phenomenon. Patients with fronto-insular stroke (FIS), behavioural variant frontotemporal dementia (bvFTD) and Alzheimer's disease (AD) show a lack of self-awareness, insight, and self-monitoring, which translate into anosognosia and daily behavioural impairments. Notably, they also present damage in key monitoring areas. While neuroscientific research on this domain has accrued in recent years, no previous study has compared monitoring performance across these brain diseases and none has applied a multiple lesion model approach combined with neuroimaging analysis. Here, we evaluated explicit and implicit monitoring in patients with focal stoke (FIS) and two types of dementia (bvFTD and AD) presenting damage in key monitoring areas. Participants performed a visual perception task and provided two types of report: confidence (explicit judgment of trust about their performance) and wagering (implicit reports which consisted in betting on their accuracy in the perceptual task). Then, damaged areas were analyzed via structural MRI to identify associations with potential behavioral deficits. In AD, inadequate confidence judgments were accompanied by poor wagering performance, demonstrating explicit and implicit monitoring impairments. By contrast, disorders of implicit monitoring in FIS and bvFTD patients occurred in the context of accurate confidence reports, suggesting a reduced ability to turn self-knowledge into appropriate wagering conducts. MRI analysis showed that ventromedial compromise was related to overconfidence, whereas fronto-temporo-insular damage was associated with excessive wagering. Therefore, joint assessment of explicit and implicit monitoring could favor a better differentiation of neurological profiles (frontal damage vs AD) and eventually contribute to delineating clinical interventions.
Topics: Aged; Alzheimer Disease; Brain; Case-Control Studies; Frontotemporal Dementia; Humans; Judgment; Magnetic Resonance Imaging; Male; Middle Aged; Monitoring, Physiologic; Neuroimaging; Stroke; Visual Perception
PubMed: 31575976
DOI: 10.1038/s41598-019-50599-x -
Zeitschrift Fur Gerontologie Und... Jun 2017Currently, there are no concrete, evidence-based default procedures to adequately assess the capacity to consent to medical treatment. This explains why different raters... (Review)
Review
BACKGROUND
Currently, there are no concrete, evidence-based default procedures to adequately assess the capacity to consent to medical treatment. This explains why different raters use individual heuristics, differing both within and between disciplines. The lack of a procedure that is standardized, validated, and equally accepted across disciplines to assess the capacity to consent to treatment has led to an uncertainty in legal and medical practice regarding appropriate action and decision making. Due to the dramatic increase in the number of patients with dementia and multimorbidity, who have to regularly consent to various medical treatments but whose capacity to consent is hindered due to cognitive impairments, this topic is particularly timely.
OBJECTIVE
The present study aims to investigate how experts of different disciplines (law, medicine, ethics) assess the capacity to consent on the basis of a case study involving a patient with dementia.
MATERIALS AND METHODS
The judgements and judgement criteria of 41 experts from various disciplines were surveyed via a self-administered questionnaire that was distributed via postal mail.
RESULTS
The results show that experts from various disciplines come to different conclusions regarding the capacity of the patient with dementia to consent.
CONCLUSION
These observations lead to the conclusion that there is an urgent need for an interdisciplinary guideline for the assessment of the capacity to consent to treatment, for interdisciplinary training, and for more interdisciplinary exchange in the assessment process.
Topics: Clinical Decision-Making; Dementia; Expert Testimony; Germany; Health Surveys; Humans; Informed Consent; Mental Competency; Needs Assessment; Patient Care Team; Physician-Patient Relations; Practice Guidelines as Topic
PubMed: 28534169
DOI: 10.1007/s00391-017-1243-1 -
Journal of Neurophysiology Aug 2017Proprioception, the sense of limb position and motion, is essential for generating accurate movements. Limb position sense has typically been studied under static...
Proprioception, the sense of limb position and motion, is essential for generating accurate movements. Limb position sense has typically been studied under static conditions (i.e., the fixed position of a limb in space), with less known about dynamic position sense (i.e., limb position during movement). Here we investigated how a person's estimate of hand position varies when using spatial or temporal information to judge the unseen hand's location during reaching. We assessed the acuity of dynamic position sense in two directions, orthogonal to hand movement, which only requires spatial information, and in line with hand movement, which has both spatial and temporal components. Our results showed that people have better proprioceptive acuity in the orthogonal condition where only spatial information is used. We then assessed whether cerebellar damage impairs proprioceptive acuity in both tasks during passive and active movement. Cerebellar patients showed reduced acuity in both tasks and in both movement conditions relative to age-matched controls. However, patients' deficits were most apparent when judgments of active movement relied on temporal information. Furthermore, both cerebellar patient and control performance correlated with the trial-to-trial variability of their active movements: subjects are worse at the proprioceptive tasks when movements are variable. Our results suggest that, during active movements, proprioceptive acuity may be reliant on the motor system's ability to predict motor output. Therefore, the resultant proprioceptive deficits occurring after cerebellar damage may be related to a more general impairment in movement prediction. We assessed limb position sense during movement in patients with cerebellar damage and found deficits in proprioceptive acuity during both passive and active movement. The effect of cerebellar damage was most apparent when individuals relied on both timing and spatial information during active movement. Thus proprioceptive acuity during active movements may be reliant on the motor system's ability to predict motor output.
Topics: Adult; Cerebellum; Electromyography; Female; Humans; Judgment; Male; Mechanoreceptors; Middle Aged; Motor Activity; Movement; Muscle, Skeletal; Physical Stimulation; Proprioception; Robotics; Spinocerebellar Degenerations; Touch; Touch Perception; Upper Extremity
PubMed: 28404825
DOI: 10.1152/jn.00417.2016