scholarly journals Functional Magnetic Resonance Imaging during Visual Perception Tasks in Adolescents Born Prematurely

Author(s):  
Annika Lind ◽  
Leena Haataja ◽  
Marja Laasonen ◽  
Virva Saunavaara ◽  
Henry Railo ◽  
...  

Abstract Objectives: Impairments in visual perception are among the most common developmental difficulties related to being born prematurely, and they are often accompanied by problems in other developmental domains. Neural activation in participants born prematurely and full-term during tasks that assess several areas of visual perception has not been studied. To better understand the neural substrates of the visual perceptual impairments, we compared behavioral performance and brain activations during visual perception tasks in adolescents born very preterm (birth weight ≤1500 g or gestational age <32 weeks) and full-term. Methods: Tasks assessing visual closure, discrimination of a deviating figure, and discrimination of figure and ground from the Motor-Free Visual Perception Test, Third Edition were performed by participants born very preterm (n = 37) and full-term (n = 34) at 12 years of age during functional magnetic resonance imaging. Results: Behavioral performance in the visual perception tasks did not differ between the groups. However, during the visual closure task, brain activation was significantly stronger in the group born very preterm in a number of areas including the frontal, anterior cingulate, temporal, and posterior medial parietal/cingulate cortices, as well as in parts of the cerebellum, thalamus, and caudate nucleus. Conclusions: Differing activations during the visual closure task potentially reflect a compensatory neural process related to premature birth or lesser neural efficiency or may be a result of the use of compensatory behavioral strategies in the study group born very preterm.

2009 ◽  
Vol 15 (3) ◽  
pp. 383-393 ◽  
Author(s):  
HELEN M. GENOVA ◽  
FRANK G. HILLARY ◽  
GLENN WYLIE ◽  
BART RYPMA ◽  
JOHN DELUCA

AbstractAlthough it is known that processing speed deficits are one of the primary cognitive impairments in multiple sclerosis (MS), the underlying neural mechanisms responsible for impaired processing speed remain undetermined. Using BOLD functional magnetic resonance imaging, the current study compared the brain activity of 16 individuals with MS to 17 healthy controls (HCs) during performance of a processing speed task, a modified version of the Symbol Digit Modalities Task. Although there were no differences in performance accuracy, the MS group was significantly slower than HCs. Although both groups showed similar activation involving the precentral gyrus and occipital cortex, the MS showed significantly less cerebral activity than HCs in bilateral frontal and parietal regions, similar to what has been reported in aging samples during speeded tasks. In the HC group, processing speed was mediated by frontal and parietal regions, as well as the cerebellum and thalamus. In the MS group, processing speed was mediated by insula, thalamus and anterior cingulate. It therefore appears that neural networks involved in processing speed differ between MS and HCs, and our findings are similar to what has been reported in aging, where damage to both white and gray matter is linked to processing speed impairments (JINS, 2009, 15, 383–393).


2012 ◽  
Vol 117 (4) ◽  
pp. 868-877 ◽  
Author(s):  
Marieke Niesters ◽  
Najmeh Khalili-Mahani ◽  
Christian Martini ◽  
Leon Aarts ◽  
Joop van Gerven ◽  
...  

Background The influence of psychoactive drugs on the central nervous system has been investigated with positron emission tomography and task-related functional magnetic resonance imaging. However, it is not known how these drugs affect the intrinsic large-scale interactions of the brain (resting-state functional magnetic resonance imaging connectivity). In this study, the effect of low-dose S(+)-ketamine on intrinsic brain connectivity was investigated. Methods Twelve healthy, male volunteers received a 2-h intravenous S(+)-ketamine infusion (first hour 20 mg/70 kg, second hour 40 mg/70 kg). Before, during, and after S(+)-ketamine administration, resting-state brain connectivity was measured. In addition, heat pain tests were performed between imaging sessions to determine ketamine-induced analgesia. A mixed-effects general linear model was used to determine drug and pain effects on resting-state brain connectivity. Results Ketamine increased the connectivity most importantly in the cerebellum and visual cortex in relation to the medial visual network. A decrease in connectivity was observed in the auditory and somatosensory network in relation to regions responsible for pain sensing and the affective processing of pain, which included the amygdala, insula, and anterior cingulate cortex. Connectivity variations related to fluctuations in pain scores were observed in the anterior cingulate cortex, insula, orbitofrontal cortex, and the brainstem, regions involved in descending inhibition of pain. Conclusions Changes in connectivity were observed in the areas that explain ketamine's pharmacodynamic profile with respect to analgesia and psychedelic and other side effects. In addition, pain and ketamine changed brain connectivity in areas involved in endogenous pain modulation.


2010 ◽  
Vol 22 (2) ◽  
pp. 362-376 ◽  
Author(s):  
Claus Lamm ◽  
Andrew N. Meltzoff ◽  
Jean Decety

Previous research on the neural underpinnings of empathy has been limited to affective situations experienced in a similar way by an observer and a target individual. In daily life we also interact with people whose responses to affective stimuli can be very different from our own. How do we understand the affective states of these individuals? We used functional magnetic resonance imaging to assess how participants empathize with the feelings of patients who reacted with no pain to surgical procedures but with pain to a soft touch. Empathy for pain of these patients activated the same areas (insula, medial/anterior cingulate cortex) as empathy for persons who responded to painful stimuli in the same way as the observer. Empathy in a situation that was aversive only for the observer but neutral for the patient recruited areas involved in self–other distinction (dorsomedial prefrontal cortex) and cognitive control (right inferior frontal cortex). In addition, effective connectivity between the latter and areas implicated in affective processing was enhanced. This suggests that inferring the affective state of someone who is not like us can rely upon the same neural structures as empathy for someone who is similar to us. When strong emotional response tendencies exist though, these tendencies have to be overcome by executive functions. Our results demonstrate that the fronto-cortical attention network is crucially involved in this process, corroborating that empathy is a flexible phenomenon which involves both automatic and controlled cognitive mechanisms. Our findings have important implications for the understanding and promotion of empathy, demonstrating that regulation of one's egocentric perspective is crucial for understanding others.


2021 ◽  
Vol 12 ◽  
Author(s):  
Sheng-Min Wang ◽  
Nak-Young Kim ◽  
Dong Woo Kang ◽  
Yoo Hyun Um ◽  
Hae-Ran Na ◽  
...  

Objective: Diverse resting-state functional magnetic resonance imaging (rs-fMRI) studies showed that rs-fMRI might be able to reflect the earliest detrimental effect of cerebral beta-amyloid (Aβ) pathology. However, no previous studies specifically compared the predictive value of different rs-fMRI parameters in preclinical AD.Methods: A total of 106 cognitively normal adults (Aβ+ group = 66 and Aβ− group = 40) were included. Three different rs-fMRI parameter maps including functional connectivity (FC), fractional amplitude of low-frequency fluctuations (fALFF), and regional homogeneity (ReHo) were calculated. Receiver operating characteristic (ROC) curve analyses were utilized to compare classification performance of the three rs-fMRI parameters.Results: FC maps showed the best classifying performance in ROC curve analysis (AUC, 0.915, p &lt; 0.001). Good but weaker performance was achieved by using ReHo maps (AUC, 0.836, p &lt; 0.001) and fALFF maps (AUC, 0.804, p &lt; 0.001). The brain regions showing the greatest discriminative power included the left angular gyrus for FC, left anterior cingulate for ReHo, and left middle frontal gyrus for fALFF. However, among the three measurements, ROI-based FC was the only measure showing group difference in voxel-wise analysis.Conclusion: Our results strengthen the idea that rs-fMRI might be sensitive to earlier changes in spontaneous brain activity and FC in response to cerebral Aβ retention. However, further longitudinal studies with larger sample sizes are needed to confirm their utility in predicting the risk of AD.


2021 ◽  
Vol 12 ◽  
Author(s):  
Andrew B. Newberg ◽  
Nancy A. Wintering ◽  
Chloe Hriso ◽  
Faezeh Vedaei ◽  
Marie Stoner ◽  
...  

Background: We measured changes in resting brain functional connectivity, with blood oxygen level dependent (BOLD) functional magnetic resonance imaging (fMRI), associated with a creative meditation practice that is augmented by clitoral stimulation and is designed to not only achieve a spiritual experience but to help individuals manage their most intimate personal relationships. Briefly, the meditative state is attained by both the male and female participants while the male stimulates the woman’s clitoris. The goal of this practice, called orgasmic meditation (OM), according to the practitioners is not sexual, but to use the focus on clitoral stimulation to facilitate a meditative state of connectedness and calm alertness between the two participants.Methods: fMRI was acquired on 20 pairs of subjects shortly following one of two states that were randomized in their order – during the OM practice or during a neutral condition. The practice is performed while the female is lying down on pillows with the clitoris exposed. During the practice, the male performs digital stimulation of the clitoris for 15 min. Resting BOLD image acquisition was performed at completion of the practice to assess changes in functional connectivity associated with the performance of the practice.Results: The results demonstrated significant changes (p &lt; 0.05) in functional connectivity associated with the OM compared to the neutral condition. For the entire group there was altered connectivity following the OM practice involving the left superior temporal lobe, the frontal lobe, anterior cingulate, and insula. In female subjects, there was altered connectivity involving the cerebellum, thalamus, inferior frontal lobe posterior parietal lobe, angular gyrus, amygdala and middle temporal gyrus, and prefrontal cortex. In males, functional connectivity changes involved the supramarginal gyrus, cerebellum, and orbitofrontal gyrus, cerebellum, parahippocampus, inferior temporal gyrus, and anterior cingulate.Conclusion: Overall, these findings suggest a complex pattern of functional connectivity changes occurring in both members of the couple pair that result from this unique meditation practice. The changes represent a hybrid of functional connectivity findings with some similarities to meditation based practices and some with sexual stimulation and orgasm. This study has broader implications for understanding the dynamic relationship between sexuality and spirituality.


2021 ◽  
Vol 15 ◽  
Author(s):  
Louis-Philippe Marquis ◽  
Sarah-Hélène Julien ◽  
Véronique Daneault ◽  
Cloé Blanchette-Carrière ◽  
Tyna Paquette ◽  
...  

Nightmares are highly dysphoric dreams that are well-remembered upon awakening. Frequent nightmares have been associated with psychopathology and emotional dysregulation, yet their neural mechanisms remain largely unknown. Our neurocognitive model posits that nightmares reflect dysfunction in a limbic-prefrontal circuit comprising medial prefrontal and anterior cingulate cortices, hippocampus, and amygdala. However, there is a paucity of studies that used brain imaging to directly test the neural correlates of nightmares. One such study compared the regional homogeneity (ReHo) of resting-state functional magnetic resonance imaging blood-oxygen level-dependent signals between frequent nightmare recallers and controls. The main results were greater regional homogeneity in the left anterior cingulate cortex and right inferior parietal lobule for the nightmare recallers than for the controls. In the present study, we aimed to document the ReHo correlates of frequent nightmares using several nightmare severity measures. We acquired resting-state functional magnetic resonance imaging data from 18 frequent nightmare recallers aged 18–35 (3 males and 15 females) and 18 age- and sex-matched controls, as well as retrospective and prospective disturbed dreaming frequency estimates and scores on the Nightmare Distress Questionnaire. While there were inconsistent results for our different analyses (group comparisons, correlational analyses for frequency estimates/Nightmare Distress scores), our results suggest that nightmares are associated with altered ReHo in frontal (medial prefrontal and inferior frontal), parietal, temporal and occipital regions, as well as some subcortical regions (thalamus). We also found a positive correlation between retrospective disturbed dreaming frequency estimates and ReHo values in the hippocampus. These findings are mostly in line with a recent SPECT study from our laboratory. Our results point to the possibility that a variety of regions, including but not limited to the limbic-prefrontal circuit of our neurocognitive model, contribute to nightmare formation.


Sign in / Sign up

Export Citation Format

Share Document