A review of functional and structural neuroimaging studies to investigate the inner speech model of auditory verbal hallucinations in schizophrenia

AbstractAlthough the pathophysiology of auditory verbal hallucinations remains uncertain, the inner speech model remains a prominent theory. A systematic review and meta-analyses of both functional and structural neuroimaging studies were performed to investigate the inner speech model. Of the 417 papers retrieved, 26 met the inclusion criteria. Meta-analyses found the left insula to be significantly active during auditory verbal hallucinations and to have a significantly reduced grey matter volume in hallucinators. Dysfunction of the left insula may contribute to the misattribution of inner speech due to its suggested roles in both inner speech production and the salience network. No significant activity was found at Broca’s area or Heschl’s gyrus during auditory verbal hallucinations. Furthermore, no structural abnormalities were found at these sites or in the arcuate fasciculi. Overall, evidence was found to both support and oppose the inner speech model. Further research should particularly include a systematic review of task-based trait studies with a focus on inner speech production and self-referential processing, and analyses of additional language-related white matter tracts.

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Mapping vulnerability to bipolar disorders

European Psychiatry ◽

10.1016/j.eurpsy.2016.01.164 ◽

2016 ◽

Vol 33 (S1) ◽

pp. S124-S125

Author(s):

M.R. Raposo ◽

M.D. Piqueras ◽

I. Martínez ◽

A.L. Galdámez ◽

A. Gil ◽

...

Keyword(s):

Systematic Review ◽

Bipolar Disorder ◽

Genetic Risk ◽

Bipolar Disorders ◽

Grey Matter Volume ◽

High Genetic Risk ◽

The Subject ◽

Mapping Vulnerability ◽

Competing Interest ◽

Left Insula

IntroductionAlthough early interventions in individuals with bipolar disorder may reduce the associated personal and economic burden, the neurobiologic markers of enhanced risk are unknown.ObjectivesThe objective of this paper is to analyze the existence of neurobiological abnormalities in individuals with genetic risk for developing bipolar disorder (HR)Material and methodsA literature search was performed in the available scientific literature on the subject study object, by searching MEDLINE.ResultsThere were 37 studies included in this systematic review. The overall sample for the systematic review included 1258 controls and 996 HR individuals. No significant differences were detected between HR individuals and controls in the selected ROIs (regions of interest): striatum, amygdala, hippocampus, pituitary and frontal lobe. The HR group showed increased grey matter volume compared with patients with established bipolar disorder. The HR individuals showed increased neural response in the left superior frontal gyrus, medial frontal gyrus and left insula compared with controls. The overall results found no significant differences between individuals at high genetic risk and controls since the magnitude of the association as corresponds to an OR < 1.5 (low association)ConclusionThere is accumulating evidence for the existence of neurobiologic abnormalities in individuals at genetic risk for bipolar disorder at various scales of investigation. The etiopathogenesis of bipolar disorder will be better elucidated by future imaging studies investigating larger and more homogeneous samples and using longitudinal designs to dissect neurobiologic abnormalities that are underlying traits of the illness from those related to psychopathologic states, such as episodes of mood exacerbation or pharmacologic treatment.Disclosure of interestThe authors have not supplied their declaration of competing interest.

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Inner Speech

10.1093/oso/9780198796640.001.0001 ◽

2018 ◽

Cited By ~ 8

Keyword(s):

Speech Production ◽

Interpersonal Communication ◽

Speech Acts ◽

Inner Speech ◽

Linguistic Expression ◽

Auditory Verbal Hallucinations ◽

Conceptual Thought ◽

The Many ◽

The One ◽

Mental Events

Inner speech lies at the chaotic intersection of numerous difficult questions in contemporary philosophy and psychology. On the one hand, inner speech utterances are private mental events of a kind. On the other, they resemble speech acts of the sort used in interpersonal communication. Thought and its linguistic expression appear to overlap. Further, inner speech is at once imagistic in nature, having a characteristic auditory-verbal phenomenology; yet it also appears suitable to carrying complex linguistic contents. In another apparent clash, inner speech episodes seem to constitute or express sophisticated trains of conceptual thought; yet, at the same time, they are deeply motoric in nature, drawing on mechanisms for speech production and perception more generally. Also, in using inner speech, we seem able both to regulate our bodily actions and, arguably, to gain a unique kind of access to our own beliefs and desires. Finally, disorders as “thought insertion” and auditory verbal hallucinations are plausibly explicable in terms of the malfunctioning of mechanisms governing speech production and perception. But there is still little on what those mechanisms are, nor in how they might be involved. This interdisciplinary volume—comprising twelve chapters by philosophers, psychologists, and neuroscientists—capitalizes on growing interest in the many questions surrounding inner speech and presents a range of new theories concerning both its nature and location within these important debates.

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Volumetric brain differences in clinical depression in association with anxiety: a systematic review with meta-analysis

Journal of Psychiatry and Neuroscience ◽

10.1503/jpn.190156 ◽

2020 ◽

Vol 45 (6) ◽

pp. 406-429

Author(s):

Daniela A. Espinoza Oyarce ◽

Marnie E. Shaw ◽

Khawlah Alateeq ◽

Nicolas Cherbuin

Keyword(s):

Systematic Review ◽

Brain Structure ◽

Late Onset ◽

Clinical Depression ◽

Cochrane Library ◽

Grey Matter Volume ◽

Intracranial Volume ◽

Brain Volumes ◽

Comorbid Anxiety ◽

Meta Analyses

Background: Structural differences associated with depression have not been confirmed in brain regions apart from the hippocampus. Comorbid anxiety has been inconsistently assessed, and may explain discrepancies in previous findings. We investigated the link between depression, comorbid anxiety and brain structure. Methods: We followed Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines (PROSPERO CRD42018089286). We searched the Cochrane Library, MEDLINE, PsycInfo, PubMed and Scopus, from database inception to Sept. 13, 2018, for MRI case–control studies that reported brain volumes in healthy adults and adults with clinical depression. We summarized mean volumetric differences using meta-analyses, and we assessed demographics, depression factors and segmentation procedure as moderators using meta-regressions. Results: We included 112 studies in the meta-analyses, assessing 4911 healthy participants and 5934 participants with depression (mean age 49.8 yr, 68.2% female). Volume effects were greater in late-onset depression and in multiple episodes of depression. Adults with depression and no comorbidity showed significantly lower volumes in the putamen, pallidum and thalamus, as well as significantly lower grey matter volume and intracranial volume; the largest effects were in the hippocampus (6.8%, p < 0.001). Adults with depression and comorbid anxiety showed significantly higher volumes in the amygdala (3.6%, p < 0.001). Comorbid anxiety lowered depression effects by 3% on average. Sex moderated reductions in intracranial volume. Limitations: High heterogeneity in hippocampus effects could not be accounted for by any moderator. Data on symptom severity and medication were sparse, but other factors likely made significant contributions. Conclusion: Depression-related differences in brain structure were modulated by comorbid anxiety, chronicity of symptoms and onset of illness. Early diagnosis of anxiety symptomatology will prove crucial to ensuring effective, tailored treatments for improving long-term mental health and mitigating cognitive problems, given the effects in the hippocampus.

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Psychological and Cognitive Aspects of Borderline Intellectual Functioning

European Psychologist ◽

10.1027/1016-9040/a000293 ◽

2017 ◽

Vol 22 (3) ◽

pp. 159-166 ◽

Cited By ~ 2

Author(s):

Bastianina Contena ◽

Stefano Taddei

Keyword(s):

Quality Of Life ◽

Systematic Review ◽

Intellectual Functioning ◽

Clinical Impact ◽

Review Of The Literature ◽

Borderline Intellectual Functioning ◽

General Quality ◽

Meta Analyses ◽

Over Time

Abstract. Borderline Intellectual Functioning (BIF) refers to a global IQ ranging from 71 to 84, and it represents a condition of clinical attention for its association with other disorders and its influence on the outcomes of treatments and, in general, quality of life and adaptation. Furthermore, its definition has changed over time causing a relevant clinical impact. For this reason, a systematic review of the literature on this topic can promote an understanding of what has been studied, and can differentiate what is currently attributable to BIF from that which cannot be associated with this kind of intellectual functioning. Using Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) criteria, we have conducted a review of the literature about BIF. The results suggest that this condition is still associated with mental retardation, and only a few studies have focused specifically on this condition.

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