Reduced ventral medial prefrontal cortex (vmPFC) volume and impaired vmPFC-default mode network integration in codeine-containing cough syrups users

2014 ◽  
Vol 134 ◽  
pp. 314-321 ◽  
Author(s):  
Ying-wei Qiu ◽  
Xiao-fei Lv ◽  
Gui-hua Jiang ◽  
Huan-huan Su ◽  
Tian Yu ◽  
...  
Keyword(s):  
Prefrontal Cortex ◽  
Medial Prefrontal Cortex ◽  
Default Mode Network ◽  
Network Integration ◽  
Default Mode ◽  
Ventral Medial Prefrontal Cortex

Cortical and subcortical changes in resting-state functional connectivity before and during an episode of postoperative delirium

2019 ◽  
Vol 53 (8) ◽  
pp. 794-806 ◽  
Author(s):  
Jooyoung Oh ◽  
Jung Eun Shin ◽  
Kyu Hyun Yang ◽  
Sunghyon Kyeong ◽  
Woo Suk Lee ◽  
...  
Keyword(s):  
Prefrontal Cortex ◽  
Medial Prefrontal Cortex ◽  
Default Mode Network ◽  
Resting State ◽  
Postoperative Delirium ◽  
Cingulate Cortex ◽  
Posterior Cingulate Cortex ◽  
Default Mode ◽  
Posterior Cingulate ◽  
Subcortical Regions

Objective: Delirium is an acute brain failure related to uncertain problems in neural connectivity, including aberrant functional interactions between remote cortical regions. This study aimed to elucidate the underlying neural mechanisms of delirium by clarifying the changes in resting-state functional connectivity induced by postoperative delirium using imaging data scanned before and after surgery. Method: Fifty-eight patients with a femoral neck fracture were preoperatively scanned using resting-state functional magnetic resonance imaging. Twenty-five patients developed postoperative delirium, and 14 of those had follow-up scans during delirium. Eighteen patients without delirium completed follow-up scans 5 or 6 days after surgery. We assessed group differences in voxel-based connectivity, in which the seeds were the posterior cingulate cortex, medial prefrontal cortex and 11 subcortical regions. Connections between the subcortical regions were also examined. Results: The results showed four major findings during delirium. Both the posterior cingulate cortex and medial prefrontal cortex were strongly connected to the dorsolateral prefrontal cortex. The posterior cingulate cortex had hyperconnectivity with the inferior parietal lobule, whereas the medial prefrontal cortex had hyperconnectivity with the frontopolar cortex and hypoconnectivity with the superior frontal gyrus. Connectivity of the striatum with the anterior cingulate cortex and insula was increased. Disconnections were found between the lower subcortical regions including the neurotransmitter origins and the striatum/thalamus in the upper level. Conclusions: Our findings suggest that cortical dysfunction during delirium is characterized by a diminution of the anticorrelation between the default mode network and task-positive regions, excessive internal connections in the posterior default mode network and a complex imbalance of internal connectivity in the anterior default mode network. These dysfunctions can be attributed to the loss of reciprocity between the default mode network and central executive network associated with defective function in the salience network, which might be closely linked to aberrant subcortical neurotransmission-related connectivity and striato-cortical connectivity.

scholarly journals Difference in default mode network subsystems in autism across childhood and adolescence

Autism ◽  
2020 ◽  
pp. 136236132096925
Author(s):  
Joe Bathelt ◽  
Hilde M Geurts
Keyword(s):  
Prefrontal Cortex ◽  
Medial Prefrontal Cortex ◽  
Default Mode Network ◽  
Medial Temporal Lobe ◽  
Data Exchange ◽  
Young Men ◽  
Data Repository ◽  
Childhood And Adolescence ◽  
Developmental Trend ◽  
Default Mode

Differences in the default mode network are among the most replicated brain-level findings in autistic individuals. Furthermore, subregions within the default mode network are associated with cognitive functions such as mentalising that are immediately relevant to cognitive theories of autism. Recent evidence suggests that the default mode network comprises partially independent subsystems that are tied to dissociable cognitive processes, specifically a medial temporal lobe subsystem involved in memory retrieval, a dorsal medial prefrontal cortex subsystem involved in social processing and a posterior cingulate cortex – anterior medial prefrontal cortex system that ties the other subsystems together. This modular organisation is thought to arise in childhood development. The current analysis investigated differences in default mode network subsystems in 193 autistic boys and young men (5–18 years) and in a group of 208 age-matched boys and young men without a diagnosis using resting-state functional magnetic resonance imaging from the data repository of the Autism Brain Imaging Data Exchange. The results indicated a developmental trend towards greater modularisation of the default mode network across childhood and adolescence in autism, mostly driven by reduced between-subnetwork connection strength. In contrast, default mode network subnetwork organisation was relatively stable in the comparison group. We suggest that these differences reflect delayed maturation of the default mode network in autism. Lay abstract Neuroimaging research has identified a network of brain regions that are more active when we daydream compared to when we are engaged in a task. This network has been named the default mode network. Furthermore, differences in the default mode network are the most consistent findings in neuroimaging research in autism. Recent studies suggest that the default mode network is composed of subnetworks that are tied to different functions, namely memory and understanding others’ minds. In this study, we investigated if default mode network differences in autism are related to specific subnetworks of the default mode network and if these differences change across childhood and adolescence. Our results suggest that the subnetworks of the default mode network are less differentiated in autism in middle childhood compared to neurotypicals. By late adolescence, the default mode network subnetwork organisation was similar in the autistic and neurotypical groups. These findings provide a foundation for future studies to investigate if this developmental pattern relates to improvements in the integration of memory and social understanding as autistic children grow up.

Brain functional changes in first-degree relatives of patients with bipolar disorder: evidence for default mode network dysfunction

2016 ◽  
Vol 46 (12) ◽  
pp. 2513-2521 ◽  
Author(s):  
S. Alonso-Lana ◽  
M. Valentí ◽  
A. Romaguera ◽  
C. Sarri ◽  
S. Sarró ◽  
...  
Keyword(s):  
Bipolar Disorder ◽  
Prefrontal Cortex ◽  
Medial Prefrontal Cortex ◽  
Default Mode Network ◽  
Healthy Controls ◽  
Whole Brain ◽  
Default Mode ◽  
Functional Changes ◽  
Significant Difference ◽  
Bipolar Patients

BackgroundRelatively few studies have investigated whether relatives of patients with bipolar disorder show brain functional changes, and these have focused on activation changes. Failure of de-activation during cognitive task performance is also seen in the disorder and may have trait-like characteristics since it has been found in euthymia.MethodA total of 20 euthymic patients with bipolar disorder, 20 of their unaffected siblings and 40 healthy controls underwent functional magnetic resonance imaging during performance of the n-back working memory task. An analysis of variance (ANOVA) was fitted to individual whole-brain maps from each set of patient–relative–matched pair of controls. Clusters of significant difference among the groups were used as regions of interest to compare mean activations/de-activations between them.ResultsA single cluster of significant difference among the three groups was found in the whole-brain ANOVA. This was located in the medial prefrontal cortex, a region of task-related de-activation in the healthy controls. Both the patients and their siblings showed significantly reduced de-activation compared with the healthy controls in this region, but the failure was less marked in the relatives.ConclusionsFailure to de-activate the medial prefrontal cortex in both euthymic bipolar patients and their unaffected siblings adds to evidence for default mode network dysfunction in the disorder, and suggests that it may act as a trait marker.

scholarly journals Beyond sleepy: structural and functional changes of the default-mode network in idiopathic hypersomnia

SLEEP ◽  
2019 ◽  
Vol 42 (11) ◽  
Author(s):  
Florence B Pomares ◽  
Soufiane Boucetta ◽  
Francis Lachapelle ◽  
Jason Steffener ◽  
Jacques Montplaisir ◽  
...  
Keyword(s):  
Prefrontal Cortex ◽  
Functional Connectivity ◽  
Medial Prefrontal Cortex ◽  
Cortical Thickness ◽  
Default Mode Network ◽  
Daytime Sleepiness ◽  
Sleep Onset ◽  
Default Mode ◽  
Functional Changes ◽  
Idiopathic Hypersomnia

Abstract Idiopathic hypersomnia (IH) is characterized by excessive daytime sleepiness but, in contrast to narcolepsy, does not involve cataplexy, sleep-onset REM periods, or any consistent hypocretin-1 deficiency. The pathophysiological mechanisms of IH remain unclear. Because of the involvement of the default-mode network (DMN) in alertness and sleep, our aim was to investigate the structural and functional modifications of the DMN in IH. We conducted multimodal magnetic resonance imaging (MRI) in 12 participants with IH and 15 good sleeper controls (mean age ± SD: 32 ± 9.6 years, range 22–53 years, nine males). Self-reported as well as objective measures of daytime sleepiness were collected. Gray matter volume and cortical thickness were analyzed to investigate brain structural differences between good sleepers and IH. Structural covariance and resting-state functional connectivity were analyzed to investigate changes in the DMN. Participants with IH had greater volume and cortical thickness in the precuneus, a posterior hub of the DMN. Cortical thickness in the left medial prefrontal cortex was positively correlated with thickness of the precuneus, and the strength of this correlation was greater in IH. In contrast, functional connectivity at rest was lower within the anterior DMN (medial prefrontal cortex) in IH, and correlated with self-reported daytime sleepiness. The present results show that IH is associated with structural and functional differences in the DMN, in proportion to the severity of daytime sleepiness, suggesting that a disruption of the DMN contributes to the clinical features of IH. Larger volume and thickness in this network might reflect compensatory changes to lower functional connectivity in IH.

Functional Imaging Changes in the Medial Prefrontal Cortex in Adult ADHD

2015 ◽  
Vol 22 (7) ◽  
pp. 679-693 ◽  
Author(s):  
José Salavert ◽  
Josep A. Ramos-Quiroga ◽  
Ana Moreno-Alcázar ◽  
Xavier Caseras ◽  
Gloria Palomar ◽  
...  
Keyword(s):  
Prefrontal Cortex ◽  
Medial Prefrontal Cortex ◽  
Functional Imaging ◽  
Default Mode Network ◽  
Adult Adhd ◽  
Control Group ◽  
Default Mode ◽  
Long Term Treatment ◽  
Back Task

Objective: Functional imaging studies have found reduced frontal activity, mainly in dorso/ventro-lateral regions and reduced task-related de-activation of the default mode network in childhood ADHD. Adult studies are fewer and inconclusive. We aimed to investigate the potential neural bases of executive function in ADHD adults, examining brain activity during N-back task performance, and to explore the potential corrective effects of long-term methylphenidate treatment. Method: We recruited a large adult ADHD-combined sample and a matched control group and obtained functional magnetic resonance imaging (fMRI) images during task. ADHD participants were subdivided in a group under long-term treatment with methylphenidate (washed out for the scan) and a treatment-naive group. Results: ADHD participants showed deficient de-activation of the medial prefrontal cortex during 2-back task, implying default mode network dysfunction. We found no relationship between blunted de-activation and treatment history. Conclusion: As de-activation failure in the medial frontal cortex is linked to lapses of attention, findings suggest a potential link to ADHD symptomatology.

scholarly journals O4.4. REAL TIME FMRI NEUROFEEDBACK TARGETING STG AND DMN REDUCES AUDITORY HALLUCINATIONS

2020 ◽  
Vol 46 (Supplement_1) ◽  
pp. S10-S10
Author(s):  
Margaret Niznikiewicz ◽  
Kana Okano ◽  
Clemens Bauer ◽  
Paul Nestor ◽  
Elizabetta Del Re ◽  
...  
Keyword(s):  
Prefrontal Cortex ◽  
Real Time ◽  
Default Mode Network ◽  
Superior Temporal Gyrus ◽  
Brain Regions ◽  
Central Executive ◽  
Auditory Hallucinations ◽  
Default Mode ◽  
Central Executive Network ◽  
Voice Recording

Abstract Background Auditory hallucinations (AH) are one of the core symptoms of schizophrenia (SZ) and constitute a significant source of suffering and disability. One third of SZ patients experience pharmacology-resistant AH, so an alternative/complementary treatment strategy is needed to alleviate this debilitating condition. In this study, real-time functional Magnetic Resonance Imaging neurofeedback (rt-fMRI NFB), a non-invasive technique, was used to help 10 SZ patients modulate their brain activity in key brain regions belonging to the network involved in the experience of auditory hallucinations. In two experiments we selected two different brain targets. 1. the superior temporal gyrus (STG) and 2. default mode network (DMN)-central executive network (CEN) connectivity. STG is a key area in the neurophysiology of AH. Hyperactivation of the default mode network (DMN) and of the superior temporal gyrus (STG) in SZ has been shown in imaging studies. Furthermore, several studies point to reduced anticorrelation between the DMN and the central executive network (CEN). Finally, DMN hyperconnectivity has been associated with positive symptoms such as AHs while reduced DMN anticorrelations have been associated with cognitive impairment. Methods In the STG-focused NFB experiment, subjects were trained to upregulate the STG activity while listening to their own voice recording and downregulate it while ignoring a stranger’s voice recording in the course of 21 min NFB session. Visual feedback was provided to subjects at the end of each run from their own STG activity in the form of a thermometer. AH were assessed with auditory hallucination scale pre-NFB and within a week after the NFB session. The DMN-CEN focused NFB experiment was conducted about 1 month later to minimize the carry over effects from the STG-focused NFB and was designed to help SZ patients modulate their DMN and CEN networks. DMN and CEN networks were defined individually for each subject. The goal of the task was to increase CEN-DMN anti-correlations. To achieve that patients were provided with meditation strategies to guide their performance. Feedback was provided in the form of a ball that traveled up if the modulation of DMN-CEN connectivity was successful and traveled down if it was not successful. AH measures were taken before the NFB session and within a week after the session. Results In the STG-focused NFB task, significant STG activation reduction was found in the comparison of pre- relative to post-NFB in the condition of ignoring another person’s voice (p<0.05), FWE-TFCE corrected. AH were also significantly reduced (p<0.01). Importantly, significant correlation was found between reductions in the STG activation and AH reductions (r=.83). In the DMN-CEN focused NFB task, significant increase in the anti-correlations between medial prefrontal cortex (mPFC) and dorsolateral prefrontal cortex (DLPFC) (p<0.05) was observed as well as significant reduction in the mPFC-PCC connectivity (p <0.05), in the pre-post NFB comparisons. AH were significantly reduced in post- relative to pre-NFB comparison (p<0.02). Finally, there was a significant correlation between individual scores in mPFC-STG connectivity and AH reductions. Discussion These the two experiments suggest that targeting both the STG BOLD activation and DMN-CEN connectivity in NFB tasks aimed at AH reduction result both in brain changes and in AH reductions. Together, these results provide strong preliminary support for the NFB use as a means to impact brain function leading to reductions in AH in SZ. Importantly, these results suggest that AH result from brain abnormalities in a network of brain regions and that targeting a brain region belonging to this network will lead to AH symptom reduction.

Acupuncture – Self-Appraisal and the Reward System

2007 ◽  
Vol 25 (3) ◽  
pp. 87-99 ◽  
Author(s):  
Thomas Lundeberg ◽  
Iréne Lund ◽  
Jan Näslund
Keyword(s):  
Prefrontal Cortex ◽  
Medial Prefrontal Cortex ◽  
Cognitive Processes ◽  
Acupuncture Treatment ◽  
Reward System ◽  
Patellofemoral Pain ◽  
Explanatory Models ◽  
Limbic Structures ◽  
Ventral Medial Prefrontal Cortex

Acupuncture is an ancient therapy with a variety of different explanatory models. A cascade of physiological effects has been reported, both in the peripheral and the central nervous system, following the insertion of a needle or light tapping of the skin. Clinical trials testing the specific claims of acupuncture have generally tried to focus on testing the efficacy of applying specific techniques and/or specified points. However, different conditions may respond differently to different modes of stimulation. Recently, it was demonstrated that both superficial and deep needling (with de qi/Hibiki) resulted in amelioration of patellofemoral pain and unpleasantness. The pleasurable aspect of the acupuncture experience has largely been ignored as it has been considered secondary to its pain alleviating effects. This aspect of acupuncture treatment is likely to be related to activation of self-appraisal and the reward system. When a patient seeks a therapist there are expectations of a specific effect. These expectations are partly based on self-relevant phenomena and self-referentia introspection and constitute the preference. Also, when asked about the effect of the treatment, processes that orientate pre-attentive anticipatory or mnemonic information and processes that mediate self-reflection and recollection are integrated together with sensory detection to enable a decision about the patient's perception of the effect of acupuncture treatment. These ‘self-appraisal’ processes are dependent on two integrated networks: a ventral medial prefrontal cortex paralimbic limbic ‘affective’ pathway and a dorsal medial prefrontal cortex cortical hippocampal ‘cognitive’ pathway. The limbic structures are implicated in the reward system and play a key role in most diseases and illness responses including chronic pain and depression, regulating mood and neuromodulatory responses (eg sensory, autonomic, and endocrine). The pleasurable and neuromodulatory aspects of acupuncture as well as ‘placebo needling’ may partly be explained by the activation or deactivation of limbic structures including the hippocampus, amygdala, and their connections with the hypothalamus. In patients with patellofemoral pain, the effects of superficial and deep needling remained for six months. These long term pain-alleviating effects have been attributed to activation of pain inhibiting systems in cortical and subcortical pathways. When considering long term effects the cortical cerebellar system needs to be taken into account. The cortical cerebellar system is probably central to the development of neural models that learn and eventually stimulate routinely executed (eg motor skills) and long term (eg pain alleviation) cognitive processes. These higher order cognitive processes are initially mediated in prefrontal cortical loci but later shift control iteratively to internal cerebellar representations of these processes. Possibly part of the long term healing effects of acupuncture may be attributed to changes in the cerebellar system thereby sparing processing load in cortical and subcortical areas. As cortical and subcortical structures are activated and/or de-activated following stimulation of receptors in the skin, disregarding site, ‘placebo or sham needling’ does not exist and conclusions drawn on the basis that it is an inert control are invalid. ‘Self’ may be seen as a shifting illusion, ceaselessly constructed and deconstructed, and the effect of acupuncture may reflect its status (as well as that of the therapist).

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