Anatomical MRI Abnormalities in Bipolar Disorder: Do They Exist and Do They Progress?

2005 ◽  
Vol 39 (4) ◽  
pp. 222-226 ◽  
Author(s):  
E. Serap Monkul ◽  
Gin S. Malhi ◽  
Jair C. Soares
Keyword(s):  
Bipolar Disorder ◽  
Prefrontal Cortex ◽  
Brain Imaging ◽  
Grey Matter ◽  
Brain Structures ◽  
Brain Regions ◽  
Anterior Cingulate ◽  
Imaging Studies ◽  
Neuroprotective Effects ◽  
Bipolar Patients

Aim: Morphometric brain imaging studies have revealed regional brain abnormalities in patients with bipolar disorder, which may play a role in illness pathophysiology. It is not known whether such changes are of neurodevelopmental, neurodegenerative, or combined origin. We reviewed the anatomical brain imaging literature in bipolar disorder, in an attempt to determine whether there is evidence to suggest that such abnormalities are progressive. Method: Literature searches were conducted using MEDLINE for the period from 1966 to June 2004, using specific key words; bipolar disorder and the names of the individual brain structures. Papers were selected according to their salience in relation to whether reported changes are progressive. Results: Available findings suggest reduced grey matter in prefrontal brain regions such as anterior cingulate and subgenual prefrontal cortex, and abnormalities in amygdala size in adult and paediatric bipolar patients. White matter hyperintensities, which are non-specific abnormalities, are also common in bipolar patients. Bipolar patients may lose more brain grey matter by ageing. There is also evidence for impaired myelination of the corpus callosum in bipolar disorder. Lithium may reverse or prevent grey matter prefrontal cortex abnormalities in bipolar patients by its neuroprotective effects. Conclusions: Both early developmental and later neurodegenerative processes may play a role in the pathophysiology of bipolar disorder. Findings from anatomical brain imaging studies implicate key regions involved in mood regulation. The evidence for the progressive nature of this illness is tentative, as no follow-up study with bipolar patients has been reported to this date.

Lithium prevents grey matter atrophy in patients with bipolar disorder: an international multicenter study

2020 ◽  
pp. 1-10
Author(s):  
Franz Hozer ◽  
Samuel Sarrazin ◽  
Charles Laidi ◽  
Pauline Favre ◽  
Melissa Pauling ◽  
...  
Keyword(s):  
Bipolar Disorder ◽  
Grey Matter ◽  
Brain Regions ◽  
Anterior Cingulate ◽  
Type I ◽  
Linear Regression Models ◽  
Neuroprotective Effects ◽  
History Of ◽  
International Multicenter Study ◽  
The Right

Abstract Background Lithium (Li) is the gold standard treatment for bipolar disorder (BD). However, its mechanisms of action remain unknown but include neurotrophic effects. We here investigated the influence of Li on cortical and local grey matter (GM) volumes in a large international sample of patients with BD and healthy controls (HC). Methods We analyzed high-resolution T1-weighted structural magnetic resonance imaging scans of 271 patients with BD type I (120 undergoing Li) and 316 HC. Cortical and local GM volumes were compared using voxel-wise approaches with voxel-based morphometry and SIENAX using FSL. We used multiple linear regression models to test the influence of Li on cortical and local GM volumes, taking into account potential confounding factors such as a history of alcohol misuse. Results Patients taking Li had greater cortical GM volume than patients without. Patients undergoing Li had greater regional GM volumes in the right middle frontal gyrus, the right anterior cingulate gyrus, and the left fusiform gyrus in comparison with patients not taking Li. Conclusions Our results in a large multicentric sample support the hypothesis that Li could exert neurotrophic and neuroprotective effects limiting pathological GM atrophy in key brain regions associated with BD.

The effects of gender on grey matter abnormalities in major psychoses: a comparative voxelwise meta-analysis of schizophrenia and bipolar disorder

2011 ◽  
Vol 42 (2) ◽  
pp. 295-307 ◽  
Author(s):  
E. Bora ◽  
A. Fornito ◽  
M. Yücel ◽  
C. Pantelis
Keyword(s):  
Bipolar Disorder ◽  
Prefrontal Cortex ◽  
Dorsolateral Prefrontal Cortex ◽  
Negative Symptoms ◽  
Grey Matter ◽  
Meta Analysis ◽  
Anterior Cingulate ◽  
Limiting Factor ◽  
Dorsolateral Prefrontal ◽  
Male Dominated

BackgroundRecent evidence from genetic and familial studies revitalized the debate concerning the validity of the distinction between schizophrenia and bipolar disorder. Comparing brain imaging findings is an important avenue to examine similarities and differences and, therefore, the validity of the distinction between these conditions. However, in contrast to bipolar disorder, most patient samples in studies of schizophrenia are predominantly male. This a limiting factor for comparing schizophrenia and bipolar disorder since male gender is associated with more severe neurodevelopmental abnormalities, negative symptoms and cognitive deficits in schizophrenia.MethodWe used a coordinate-based meta-analysis technique to compare grey matter (GM) abnormalities in male-dominated schizophrenia, gender-balanced schizophrenia and bipolar disorder samples based on published voxel-based morphometry (VBM) studies. In total, 72 English-language, peer reviewed articles published prior to January 2011 were included. All reports used VBM for comparing schizophrenia or bipolar disorder with controls and reported whole-brain analyses in standard stereotactic space.ResultsGM reductions were more extensive in male-dominated schizophrenia compared to gender-balanced bipolar disorder and schizophrenia. In gender-balanced samples, GM reductions were less severe. Compared to controls, GM reductions were restricted to dorsal anterior cingulate cortex (ACC) and dorsolateral prefrontal cortex in schizophrenia and ACC and bilateral fronto-insular cortex in bipolar disorder.ConclusionsWhen gender is controlled, GM abnormalities in bipolar disorder and schizophrenia are mostly restricted to regions that have a role in emotional and cognitive aspects of salience respectively. Dorsomedial and dorsolateral prefrontal cortex were the only regions that showed greater GM reductions in schizophrenia compared to bipolar disorder.

A Review of Neuroimaging Studies on Working Memory Paradigms in Patients with Bipolar Disorder

2019 ◽  
Vol 18 (21) ◽  
pp. 1883-1892 ◽  
Author(s):  
Asen Beshkov ◽  
Mariyan Topolov ◽  
Feryhan Ahmed-Popova ◽  
Stefan Sivkov
Keyword(s):  
Bipolar Disorder ◽  
Working Memory ◽  
Cognitive Neuroscience ◽  
Mental Disease ◽  
Brain Structures ◽  
Functional Magnetic Resonance ◽  
Resonance Imaging ◽  
Imaging Studies ◽  
Powerful Means ◽  
Bipolar Patients

New brain technologies including neuroimaging studies are powerful means for providing new insights into clinical and cognitive neuroscience. Bipolar disorder is a severe chronic phasic mental disease characterized by various cognitive dysfunctions. Working memory is one prominent domain of cognitive impairment in bipolar disorder. Disruptions in working memory are observed even in euthymic bipolar patients which makes it a potential endophenotypic marker for the disorder. Finding such markers may help in providing firm neurobiological basis for psychiatric nosologies and symptomatic presentations. This review aims to summarize some of the important aspects of findings from functional magnetic resonance imaging studies on the activation of brain structures in relation to working memory paradigms.

Reproducibility of human brain activity evoked by esophageal stimulation using functional magnetic resonance imaging

2007 ◽  
Vol 293 (1) ◽  
pp. G188-G197 ◽  
Author(s):  
Steven J. Coen ◽  
Lloyd J. Gregory ◽  
Lidia Yágüez ◽  
Edson Amaro ◽  
Mick Brammer ◽  
...  
Keyword(s):  
Brain Imaging ◽  
Anterior Cingulate Cortex ◽  
Somatosensory Cortex ◽  
Functional Mri ◽  
Brain Activity ◽  
Brain Regions ◽  
Anterior Cingulate ◽  
Primary Somatosensory Cortex ◽  
Imaging Studies ◽  
Painful Stimulation

Functional MRI is a popular tool for investigating central processing of visceral pain in healthy and clinical populations. Despite this, the reproducibility of the neural correlates of visceral sensation by use of functional MRI remains unclear. The aim of the present study was to address this issue. Seven healthy right-handed volunteers participated in the study. Blood oxygen level-dependent contrast images were acquired at 1.5 T while subjects received nonpainful and painful phasic balloon distensions (“on-off” block design, 10 stimuli per “on” period, 0.3 Hz) to the distal esophagus. This procedure was repeated on two further occasions to investigate reproducibility. Painful stimulation resulted in highly reproducible activation over three scanning sessions in the anterior insula, primary somatosensory cortex, and anterior cingulate cortex. A significant decrease in strength of activation occurred from session 1 to session 3 in the anterior cingulate cortex, primary somatosensory cortex, and supplementary motor cortex, which may be explained by an analogous decrease in pain ratings. Nonpainful stimulation activated similar brain regions to painful stimulation, but with greater variability in signal strength and regions of activation between scans. Painful stimulation of the esophagus produces robust activation in many brain regions. A decrease in subjective perception of pain and brain activity from the first to the final scan suggests that serial brain imaging studies may be affected by habituation. These findings indicate that for brain imaging studies that require serial scanning, development of experimental paradigms that control for the effect of habituation is necessary.

Brain-Imaging Studies of Posttraumatic Stress Disorder

CNS Spectrums ◽  
2003 ◽  
Vol 8 (9) ◽  
pp. 641-650 ◽  
Author(s):  
Israel Liberzon ◽  
K. Luan Phan
Keyword(s):  
Posttraumatic Stress Disorder ◽  
Brain Imaging ◽  
Posttraumatic Stress ◽  
Stress Disorder ◽  
Brain Regions ◽  
Anterior Cingulate ◽  
Aminobutyric Acid ◽  
Structural Studies ◽  
Imaging Studies ◽  
Activation Patterns

ABSTRACTBrain-imaging studies of posttraumatic stress disorder (PTSD) have rapidly increased in recent years. Structural studies have identified potential smaller volumes of the hippocampus of traumatized and/or PTSD subjects. Functional activation studies have implicated hyperactive or altered functioning of brain regions, such as the amygdala and the insula, and a failure to engage emotional regulatory structures, such as the medial prefrontal and anterior cingulate cortex. Recent neurochemical investigations have suggested that neuromodulatory systems (eg, γ-aminobutyric acid, μ-opioid) may underlie these aberrant brain activation patterns. This article reviews the literature on structural, functional, and neurochemical brain-imaging studies of PTSD.

scholarly journals Cerebrovascular responses of the rat brain to noxious stimuli as examined by functional near-infrared whole brain imaging

2012 ◽  
Vol 107 (10) ◽  
pp. 2853-2865 ◽  
Author(s):  
Ji-Wei He ◽  
Fenghua Tian ◽  
Hanli Liu ◽  
Yuan Bo Peng
Keyword(s):  
Brain Imaging ◽  
Near Infrared ◽  
Small Animal ◽  
Nir Spectroscopy ◽  
Brain Regions ◽  
Anterior Cingulate ◽  
Hemodynamic Changes ◽  
Whole Brain ◽  
Brain Hemodynamics

While near-infrared (NIR) spectroscopy has been increasingly used to detect stimulated brain activities with an advantage of dissociating regional oxy- and deoxyhemoglobin concentrations simultaneously, it has not been utilized much in pain research. Here, we investigated and demonstrated the feasibility of using this technique to obtain whole brain hemodynamics in rats and speculated on the functional relevance of the NIR-based hemodynamic signals during pain processing. NIR signals were emitted and collected using a 26-optodes array on rat's dorsal skull surface after the removal of skin. Following the subcutaneous injection of formalin (50 μl, 3%) into a hindpaw, several isolable brain regions showed hemodynamic changes, including the anterior cingulate cortex, primary/secondary somatosensory cortexes, thalamus, and periaqueductal gray ( n = 6). Time courses of hemodynamic changes in respective regions matched with the well-documented biphasic excitatory response. Surprisingly, an atypical pattern (i.e., a decrease in oxyhemoglobin concentration with a concomitant increase in deoxyhemoglobin concentration) was seen in phase II. In a separate group of rats with innocuous brush and noxious pinch of the same area ( n = 11), results confirmed that the atypical pattern occurred more likely in the presence of nociception than nonpainful stimulation, suggesting it as a physiological substrate when the brain processes pain. In conclusion, the NIR whole brain imaging provides a useful alternative to study pain in vivo using small-animal models. Our results support the notion that neurovascular response patterns depend on stimuli, bringing attention to the interpretation of vascular-based neuroimaging data in studies of pain.

Brain-imaging studies of language production

2007 ◽  
pp. 546-564
Author(s):  
Peter Indefrey
Keyword(s):  
Brain Imaging ◽  
Language Production ◽  
Brain Regions ◽  
Code Word ◽  
Word Production ◽  
Production Model ◽  
Exact Nature ◽  
Lexical Selection ◽  
Imaging Studies ◽  
Independent Evidence

This article adopts the production model of Levelt to discuss brain imaging studies of continuous speech. Conclusions about the involvement of brain regions in processes of language production are mainly drawn on the basis of the presence or absence of processing components of speaking in certain experimental tasks. Such conclusions are largely theory independent, because differences between current models do not concern the assumed processing levels but the exact nature of the information flow between them. In a second step, the article tests some of these conclusions by comparing the few available data on activation time courses of brain regions and independent evidence on the timing of processes in language production. It also discusses brain regions involved in word production, conceptually driven lexical selection, phonological code (word form) retrieval, phonological encoding, phonetic encoding and articulation, self-monitoring, whether the hemodynamic core areas are necessary for word production, and bilingual language production.

Brain Imaging Studies in Bipolar Disorder

2007 ◽  
pp. 161-187
Author(s):  
E. SerapMonkul ◽  
Paolo Brambilla ◽  
Fabiano G. Nery ◽  
John P. Hatch ◽  
Jair C. Soares
Keyword(s):  
Bipolar Disorder ◽  
Brain Imaging ◽  
Imaging Studies

scholarly journals Structural covariance and cortical reorganisation in schizophrenia: a MRI-based morphometric study

2018 ◽  
Vol 49 (3) ◽  
pp. 412-420 ◽  
Author(s):  
Lena Palaniyappan ◽  
Olha Hodgson ◽  
Vijender Balain ◽  
Sarina Iwabuchi ◽  
Penny Gowland ◽  
...  
Keyword(s):  
Grey Matter ◽  
Early Stage ◽  
Brain Regions ◽  
Significant Loss ◽  
Anterior Cingulate ◽  
Morphometric Study ◽  
Grey Matter Volume ◽  
Structural Covariance ◽  
Matter Volume ◽  
Functional Defect

AbstractBackgroundIn patients with schizophrenia, distributed abnormalities are observed in grey matter volume. A recent hypothesis posits that these distributed changes are indicative of a plastic reorganisation process occurring in response to a functional defect in neuronal information transmission. We investigated the structural covariance across various brain regions in early-stage schizophrenia to determine if indeed the observed patterns of volumetric loss conform to a coordinated pattern of structural reorganisation.MethodsStructural magnetic resonance imaging scans were obtained from 40 healthy adults and 41 age, gender and parental socioeconomic status matched patients with schizophrenia. Volumes of grey matter tissue were estimated at the regional level across 90 atlas-based parcellations. Group-level structural covariance was studied using a graph theoretical framework.ResultsPatients had distributed reduction in grey matter volume, with high degree of localised covariance (clustering) compared with controls. Patients with schizophrenia had reduced centrality of anterior cingulate and insula but increased centrality of the fusiform cortex, compared with controls. Simulating targeted removal of highly central nodes resulted in significant loss of the overall covariance patterns in patients compared with controls.ConclusionRegional volumetric deficits in schizophrenia are not a result of random, mutually independent processes. Our observations support the occurrence of a spatially interconnected reorganisation with the systematic de-escalation of conventional ‘hub’ regions. This raises the question of whether the morphological architecture in schizophrenia is primed for compensatory functions, albeit with a high risk of inefficiency.

Lexical Ambiguity

2018 ◽  
pp. 95-117
Author(s):  
Jennifer Rodd
Keyword(s):  
Brain Imaging ◽  
Language Comprehension ◽  
Lexical Ambiguity ◽  
Brain Regions ◽  
Contextual Cues ◽  
Imaging Studies ◽  
Word Meanings ◽  
Frontal Brain ◽  
Ambiguous Words ◽  
Multiple Meanings

This chapter on lexical ambiguity examines how words with multiple meanings are learned, stored, and processed. Lexical ambiguity is ubiquitous: over 80% of common English words have more than one dictionary entry, with some words having very many different definitions. Being able to learn and process ambiguous words is therefore critical for skilled language comprehension. This chapter reviews experiments that indicate that ambiguous words can be relatively challenging to learn, and that the competition between alternative word meanings can delay processing of these words relative to unambiguous words. However, when ambiguous words occur within sentences readers/listeners can rapidly use contextual cues to select the most likely meaning, and if necessary reinterpret the sentence in the light of subsequent information. The chapter also reviews evidence from brain imaging studies that reveals the network of temporal and frontal brain regions that are known to be important for representing and processing ambiguous words.

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