Decision letter for "Detection of memory‐ and learning‐ related brain connectivity changes following trace eyeblink‐conditioning using resting‐state functional magnetic resonance imaging in the awake rabbit"

AbstractIn recent years, there has been considerable research interest in the study of brain connectivity using the resting state functional magnetic resonance imaging (rsfMRI). Studies have explored the brain networks and connection between different brain regions. These studies have revealed interesting new findings about the brain mapping as well as important new insights in the overall organization of functional communication in the brain network. In this paper, after a general discussion of brain networks and connectivity imaging, the brain connectivity and resting state networks are described with a focus on rsfMRI imaging in stroke studies. Then, techniques for preprocessing of the rsfMRI for stroke patients are reviewed, followed by brain connectivity processing techniques. Recent research on brain connectivity using rsfMRI is reviewed with an emphasis on stroke studies. The authors hope this paper generates further interest in this emerging area of computational neuroscience with potential applications in rehabilitation of stroke patients.

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Effect of Subanesthetic Ketamine on Intrinsic Functional Brain Connectivity

Anesthesiology ◽

10.1097/aln.0b013e31826a0db3 ◽

2012 ◽

Vol 117 (4) ◽

pp. 868-877 ◽

Cited By ~ 89

Author(s):

Marieke Niesters ◽

Najmeh Khalili-Mahani ◽

Christian Martini ◽

Leon Aarts ◽

Joop van Gerven ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

Functional Magnetic Resonance Imaging ◽

Anterior Cingulate Cortex ◽

Resting State ◽

Brain Connectivity ◽

Cingulate Cortex ◽

Anterior Cingulate ◽

Functional Magnetic Resonance ◽

Resonance Imaging

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.

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