scholarly journals Discrete Parieto-Frontal Functional Connectivity Related to Grasping

2009 ◽  
Vol 101 (3) ◽  
pp. 1267-1282 ◽  
Author(s):  
Noriaki Hattori ◽  
Hiroshi Shibasaki ◽  
Lewis Wheaton ◽  
Tao Wu ◽  
Masao Matsuhashi ◽  
...  
Keyword(s):  
Functional Connectivity ◽  
Dorsolateral Prefrontal Cortex ◽  
Sensorimotor Integration ◽  
Interaction Analysis ◽  
Premotor Cortex ◽  
Dorsolateral Prefrontal ◽  
Neuronal Connections ◽  
Psychophysiological Interaction ◽  
Mri Study ◽  
Flow Of Information

The human inferior parietal lobule (IPL) is known to have neuronal connections with the frontal lobe, and these connections have been shown to be associated with sensorimotor integration to perform various types of movement such as grasping. The function of these anatomical connections has not been fully investigated. We studied the judgment of graspability of objects in an event-related functional MRI study in healthy subjects, and found activation in two different regions within IPL: one in the left dorsal IPL extending to the intraparietal sulcus and the other in the left ventral IPL. The former region was activated only in the judgment of graspable objects, whereas the latter was activated in the judgment of both graspable and nongraspable objects although the activation was greater for the graspable objects. Psychophysiological interaction analysis showed that these regions had similar but discrete functional connectivity to the lateral and medial frontal cortices. In relation to this particular task, the left dorsal IPL had functional connectivity to the left ventral premotor cortex, supplementary motor area (SMA) and right cerebellar cortex, whereas the left ventral IPL had functional connectivity to the left dorsolateral prefrontal cortex and pre-SMA. These findings suggest that the connection from the left dorsal IPL is associated specifically with automatic flow of information about grasping behavior. By contrast, the connection from the left ventral IPL might be related to motor imagination or enhanced external attention to the presented stimuli.

Effects of unilateral deactivations of dorsolateral prefrontal cortex and anterior cingulate cortex on saccadic eye movements

2014 ◽  
Vol 111 (4) ◽  
pp. 787-803 ◽  
Author(s):  
Michael J. Koval ◽  
R. Matthew Hutchison ◽  
Stephen G. Lomber ◽  
Stefan Everling
Keyword(s):  
Prefrontal Cortex ◽  
Eye Movements ◽  
Functional Connectivity ◽  
Anterior Cingulate Cortex ◽  
Dorsolateral Prefrontal Cortex ◽  
Saccadic Eye Movements ◽  
Cingulate Cortex ◽  
Anterior Cingulate ◽  
Dorsolateral Prefrontal ◽  
Single Neuron Recording

The dorsolateral prefrontal cortex (dlPFC) and anterior cingulate cortex (ACC) have both been implicated in the cognitive control of saccadic eye movements by single neuron recording studies in nonhuman primates and functional imaging studies in humans, but their relative roles remain unclear. Here, we reversibly deactivated either dlPFC or ACC subregions in macaque monkeys while the animals performed randomly interleaved pro- and antisaccades. In addition, we explored the whole-brain functional connectivity of these two regions by applying a seed-based resting-state functional MRI analysis in a separate cohort of monkeys. We found that unilateral dlPFC deactivation had stronger behavioral effects on saccades than unilateral ACC deactivation, and that the dlPFC displayed stronger functional connectivity with frontoparietal areas than the ACC. We suggest that the dlPFC plays a more prominent role in the preparation of pro- and antisaccades than the ACC.

scholarly journals The Effects of Functionally Guided, Connectivity-Based rTMS on Amygdala Activation

2021 ◽  
Vol 11 (4) ◽  
pp. 494
Author(s):  
Lysianne Beynel ◽  
Ethan Campbell ◽  
Maria Naclerio ◽  
Jeffrey T. Galla ◽  
Angikar Ghosal ◽  
...  
Keyword(s):  
Functional Connectivity ◽  
Psychiatric Disorders ◽  
Interaction Analysis ◽  
Repetitive Transcranial Magnetic Stimulation ◽  
Preliminary Evidence ◽  
Therapeutic Effects ◽  
Subcortical Structures ◽  
Video Clips ◽  
Amygdala Activation ◽  
Psychophysiological Interaction

While repetitive transcranial magnetic stimulation (rTMS) is widely used to treat psychiatric disorders, innovations are needed to improve its efficacy. An important limitation is that while psychiatric disorders are associated with fronto-limbic dysregulation, rTMS does not have sufficient depth penetration to modulate affected subcortical structures. Recent advances in task-related functional connectivity provide a means to better link superficial and deeper cortical sources with the possibility of increasing fronto-limbic modulation to induce stronger therapeutic effects. The objective of this pilot study was to test whether task-related, connectivity-based rTMS could modulate amygdala activation through its connectivity with the medial prefrontal cortex (mPFC). fMRI was collected to identify a node in the mPFC showing the strongest connectivity with the amygdala, as defined by psychophysiological interaction analysis. To promote Hebbian-like plasticity, and potentially stronger modulation, 5 Hz rTMS was applied while participants viewed frightening video-clips that engaged the fronto-limbic network. Significant increases in both the mPFC and amygdala were found for active rTMS compared to sham, offering promising preliminary evidence that functional connectivity-based targeting may provide a useful approach to treat network dysregulation. Further research is needed to better understand connectivity influences on rTMS effects to leverage this information to improve therapeutic applications.

scholarly journals Altered Long- and Short-Range Functional Connectivity in Patients with Betel Quid Dependence: A Resting-State Functional MRI Study

2016 ◽  
Vol 40 (6) ◽  
pp. 1626-1636 ◽  
Author(s):  
Tao Liu ◽  
Jianjun Li ◽  
Zhiqiang Zhang ◽  
Qiang Xu ◽  
Guangming Lu ◽  
...  
Keyword(s):  
Functional Connectivity ◽  
Long Range ◽  
Short Range ◽  
Anterior Cingulate ◽  
Betel Quid ◽  
Posterior Lobe ◽  
Functional Connectivity Density ◽  
Dorsolateral Prefrontal ◽  
The Right ◽  
Mri Study

Objective: Addiction is a chronic relapsing brain disease. Brain structural abnormalities may constitute an abnormal neural network that underlies the risk of drug dependence. We hypothesized that individuals with Betel Quid Dependence (BQD) have functional connectivity alterations that can be described by long- and short-range functional connectivity density(FCD) maps. Methods: We tested this hypothesis using functional magnetic resonance imaging (fMRI) data from subjects of the Han ethnic group in Hainan, China. Here, we examined BQD individuals (n = 33) and age-, sex-, and education-matched healthy controls (HCs) (n = 32) in a rs-fMRI study to observe FCD alterations associated with the severity of BQD. Results: Compared with HCs, long-range FCD was decreased in the right anterior cingulate cortex (ACC) and increased in the left cerebellum posterior lobe (CPL) and bilateral inferior parietal lobule (IPL) in the BQD group. Short-range FCD was reduced in the right ACC and left dorsolateral prefrontal cortex (dlPFC), and increased in the left CPL. The short-range FCD alteration in the right ACC displayed a negative correlation with the Betel Quid Dependence Scale (BQDS) (r=-0.432, P=0.012), and the long-range FCD alteration of left IPL showed a positive correlation with the duration of BQD(r=0.519, P=0.002) in BQD individuals. Conclusions: fMRI revealed differences in long- and short- range FCD in BQD individuals, and these alterations might be due to BQ chewing, BQ dependency, or risk factors for developing BQD.

scholarly journals Mechanisms of transcranial magnetic stimulation in the treatment of anorexia nervosa

BJPsych Open ◽  
2021 ◽  
Vol 7 (S1) ◽  
pp. S49-S50
Author(s):  
Lydia Shackshaft
Keyword(s):  
Anorexia Nervosa ◽  
Prefrontal Cortex ◽  
Functional Connectivity ◽  
Resting State ◽  
High Frequency ◽  
Magnetic Stimulation ◽  
Dorsolateral Prefrontal Cortex ◽  
Resting State Functional Connectivity ◽  
Dorsolateral Prefrontal ◽  
Neurophysiological Mechanisms

AimsSevere and Enduring Anorexia Nervosa (SE-AN) is a challenging condition to treat, with limited therapeutic options, high morbidity, and the highest mortality rates of any psychiatric illness. Repetitive Transcranial Magnetic Stimulation (rTMS) is an emerging treatment option, as evidence demonstrates promising efficacy in improving mood and reducing core Anorexia Nervosa symptoms, as well as safety and tolerability to patients. We aimed to investigate the neurophysiological mechanisms of rTMS use in SE-AN patients by assessing changes in resting state functional connectivity, in the first functional neuroimaging analysis investigating rTMS effects in Anorexia Nervosa patients.Method26 females with a current diagnosis of SE-AN received 20 sessions of sham or real high frequency rTMS (10 hertz) to the left dorsolateral prefrontal cortex in a randomised double-blind trial. Resting-state functional magnetic resonance imaging was performed before and after rTMS. Neural correlates of rTMS treatment were identified using a seed-based functional connectivity analysis with the left dorsolateral prefrontal cortex and bilateral amygdalae as regions of interest. Functional connectivity differences were analysed using t-contrasts in a mixed ANOVA (flexible factorial analysis) to assess interactions between treatment group (real rTMS vs sham) and time-point (pre or post TMS).ResultNo statistically significant changes in resting-state functional connectivity were observed post-rTMS compared to baseline in participants receiving active rTMS compared to sham. Increased functional connectivity between the left amygdala and left pre-supplementary motor area was observed to reach cluster-wise significance (PFWE < 0.05). However, after Bonferroni correction for multiple comparisons (3 seed regions), this did not reach the significance threshold PFWE <0.017.ConclusionThis study highlights the need for further investigation of neurophysiological mechanisms, including resting-state functional connectivity modulation, resulting from rTMS to the dorsolateral prefrontal cortex in SE-AN patients. This requires higher powered studies to account for heterogeneity in treatment response. We have provided some indication that high frequency rTMS may have therapeutic benefit in SE-AN by modification of functional connectivity between prefrontal and limbic brain regions, resulting in improved top-down cognitive control over emotional processing and ability to enact goal-directed behaviours, enabling secondary reductions in eating disorder behaviours.

scholarly journals Locations for noninvasive brain stimulation in treating depressive disorders: A combination of meta-analysis and resting-state functional connectivity analysis

2020 ◽  
Vol 54 (6) ◽  
pp. 582-590 ◽  
Author(s):  
Binlong Zhang ◽  
Jiao Liu ◽  
Tuya Bao ◽  
Georgia Wilson ◽  
Joel Park ◽  
...  
Keyword(s):  
Prefrontal Cortex ◽  
Functional Connectivity ◽  
Brain Stimulation ◽  
Dorsolateral Prefrontal Cortex ◽  
Depressive Disorders ◽  
Meta Analysis ◽  
Resting State Functional Connectivity ◽  
Noninvasive Brain Stimulation ◽  
Brain Surface ◽  
Dorsolateral Prefrontal

Objective: Many noninvasive brain stimulation techniques have been applied to treat depressive disorders. However, the target brain region in most noninvasive brain stimulation studies is the dorsolateral prefrontal cortex. Exploring new stimulation locations may improve the efficacy of noninvasive brain stimulation for depressive disorders. We aimed to explore potential noninvasive brain stimulation locations for depressive disorders through a meta-analysis and a functional connectivity approach. Methods: We conducted a meta-analysis of 395 functional magnetic resonance imaging studies to identify depressive disorder–associated brain regions as regions of interest. Then, we ran resting-state functional connectivity analysis with three different pipelines in 40 depression patients to find brain surface regions correlated with these regions of interest. The 10–20 system coordinates corresponding to these brain surface regions were considered as potential locations for noninvasive brain stimulation. Results: The 10–20 system coordinates corresponding to the bilateral dorsolateral prefrontal cortex, bilateral inferior frontal gyrus, medial prefrontal cortex, supplementary motor area, bilateral supramarginal gyrus, bilateral primary motor cortex, bilateral operculum, left angular gyrus and right middle temporal gyrus were identified as potential locations for noninvasive brain stimulation in depressive disorders. The coordinates were: posterior to F3, posterior to F4, superior to F3, posterior to F7, anterior to C4, P3, midpoint of F7–T3, posterior to F8, anterior to C3, midpoint of Fz–Cz, midpoint of Fz–Fp1, anterior to T4, midpoint of C3–P3, and anterior to C4. Conclusion: Our study identified several potential noninvasive brain stimulation locations for depressive disorders, which may serve as a basis for future clinical investigations.

scholarly journals Brain Functional Connectivity Correlates of Response in the 7.5% CO2 Inhalational Model of Generalized Anxiety Disorder: A Pilot Study

2020 ◽  
Vol 23 (4) ◽  
pp. 268-273
Author(s):  
Nathan T M Huneke ◽  
M John Broulidakis ◽  
Angela Darekar ◽  
David S Baldwin ◽  
Matthew Garner
Keyword(s):  
Anxiety Disorder ◽  
Functional Connectivity ◽  
Generalized Anxiety Disorder ◽  
Interaction Analysis ◽  
Generalized Anxiety ◽  
Affective Valence ◽  
Potential Threat ◽  
Midcingulate Cortex ◽  
Psychophysiological Interaction ◽  
Co2 Challenge

Abstract Background The 7.5% CO2 inhalational model can be used to explore potential treatments for generalized anxiety disorder. However, it is unknown how inter-individual variability in the functional architecture of negative affective valence systems might relate to anxiogenic response in this model. Methods A total of 13 healthy volunteers underwent functional magnetic resonance imaging during a passive emotional face perception task. We explored task-evoked functional connectivity in the potential threat system through generalized psychophysiological interaction analysis. Within 7 days, these participants underwent prolonged 7.5% CO2 inhalation, and results from the generalized psychophysiological interaction analysis were correlated with CO2 outcome measures. Results Functional connectivity between ventromedial prefrontal cortex and right amygdala positively correlated with heart rate and subjective anxiety, while connectivity between midcingulate cortex and left amygdala negatively correlated with anxiety during CO2 challenge. Conclusions Response to CO2 challenge correlated with task-evoked functional connectivity in the potential threat system. Further studies should assess whether this translates into clinical populations.

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