Publications by authors named "Meighen Roes"

Auditory verbal hallucinations (AVHs) involve perceptions, often voices, in the absence of external stimuli, and rank among the most common symptoms of schizophrenia. Metrical stress evaluation requires determination of the stronger syllable in words, and therefore requires auditory imagery, of interest for investigation of hallucinations in schizophrenia. The current functional magnetic resonance imaging study provides an updated whole-brain network analysis of a previously published study on metrical stress, which showed reduced directed connections between Broca's and Wernicke's regions of interest (ROIs) for hallucinations.

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Background: Brain networks involved in language, attentional and response processes are detectable by fMRI during lexical decision (LD). Here, we investigated possible abnormalities in the functional networks involved in LD in patients with bipolar disorder (BD).

Methods: fMRI and behavioural data were compared between BD (n = 25) and control (n = 21), with groups matched for age and sex.

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Background: While advances in the field of functional magnetic resonance imaging (fMRI) provide new opportunities to study brain networks underlying the experience of hallucinations in psychosis, there are methodological challenges unique to symptom-capture studies.

Study Design: We extracted brain networks activated during hallucination-capture for schizophrenia patients when fMRI data collected from two sites was merged (combined = 27). A multidimensional analysis technique was applied, which would allow separation of brain networks involved in the hallucinatory experience itself from those involved in the motor response of indicating the beginning and end of the perceived hallucinatory experience.

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Delusions in schizophrenia are false beliefs that are assigned certainty and not afforded the scrutiny that normally gives rise to doubt, even under conditions of weak evidence. The goal of the current functional magnetic resonance imaging (fMRI) study is to identify the brain network(s) involved in gathering information under conditions of weak evidence, in people with schizophrenia experiencing delusions. fMRI activity during probabilistic reasoning in people with schizophrenia experiencing delusions (n = 29) compared to people with schizophrenia not experiencing delusions (n = 41) and healthy controls (n = 41) was observed when participants made judgments based on evidence that weakly or strongly matched (or mismatched) with the focal hypothesis.

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Hallucinatory experiences (HEs) can be pronounced in psychosis, but similar experiences also occur in nonclinical populations. Cognitive mechanisms hypothesized to underpin HEs include dysfunctional source monitoring, heightened signal detection, and impaired attentional processes. Using data from an international multisite study on non-clinical participants (N = 419), we described the overlap between two sets of variables - one measuring cognition and the other HEs - at the level of individual items.

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Background: Deficits in relational episodic memory encoding are characteristic of schizophrenia (SZ), but whole-brain multivariate analyses of these deficits have been lacking. Open science has provided task-based functional magnetic resonance imaging (fMRI) data investigating paired associate encoding in SZ, but it has not yet been mobilized to address this gap in the literature. Therefore, in this study, we use previously unpublished task fMRI data to conduct the first network-level investigation of impaired relational episodic encoding in SZ.

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Combining structural (sMRI) and functional magnetic resonance imaging (fMRI) data in schizophrenia patients with and without auditory hallucinations (9 SZ_AVH, 12 SZ_nAVH), 18 patients with bipolar disorder, and 22 healthy controls, we examined whether cortical thinning was associated with abnormal activity in functional brain networks associated with auditory hallucinations. Language-task fMRI data were combined with mean cortical thickness values from 148 brain regions in a constrained principal component analysis (CPCA) to identify brain structure-function associations predictable from group differences. Two components emerged from the multimodal analysis.

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Aim: Individual Placement and Support is an effective vocational intervention for increasing competitive employment for people with severe mental illness. Little is known, however, about its effectiveness in the context of early psychosis. This study assesses improvements in clients' employment in a phase of illness during which functional abilities often decline.

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Menopause is associated with cognitive decline, and hormone therapies (HTs) may improve cognition depending on type and timing of HTs. Previous parity may influence cognition in later life. We investigated how primiparity and long-term ovariectomy influence cognition, neurogenesis, hormones, cytokines, and neuronal activation in middle-aged rats in response to Premarin, an HT.

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Sex differences in neurological disease exist in incidence, severity, progression, and symptoms and may ultimately influence treatment. Cognitive disturbances are frequent in neuropsychiatric disease with men showing greater cognitive impairment in schizophrenia, but women showing more severe dementia and cognitive decline with Alzheimer's disease. Although there are no overall differences in intelligence between the sexes, men, and women demonstrate slight but consistent differences in a number of cognitive domains.

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Social anxiety disorder is characterized by marked interpersonal impairment, particularly when presenting with comorbid major depression. However, the foundational social-cognitive skills that underlie interpersonal impairment in comorbid and non-comorbid manifestations of SAD has to date received very little empirical investigation. In a sample of 119 young adults, the current study examined differences in theory of mind (ToM), defined as the ability to decode and reason about others' mental states, across four groups: (a) non-comorbid SAD; (b) non-comorbid Lifetime MDD; (c) comorbid SAD and Lifetime MDD; and (d) healthy control.

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