Brain research
-
Randomized Controlled Trial
Effects of mild traumatic brain injury and post-traumatic stress disorder on resting-state default mode network connectivity.
Mild traumatic brain injury (mTBI) and post-traumatic stress disorder (PTSD) are common outcomes for service members. Abnormal connectivity within neural networks has been reported in the resting brain of mTBI and PTSD patients, respectively; however, the potential role of PTSD in changes to neural networks following injury has not been studied in detail. Using a data-driven approach, the present analysis aimed to elucidate resting state functional connectivity in the default mode network (DMN) in those with mTBI only and those with comorbid mTBI and PTSD. ⋯ For all subjects with mTBI, network connectivity correlated inversely with PTSD checklist score (p < 0.05). Additionally, distinct associations (p < 0.05) between medial prefrontal cortex connectivity and PTSD symptoms and, separately, posterior cingulate cortex connectivity and mTBI-related cognitive deficits were found. To our knowledge, this is the first study to report a differential relationship between DMN components and both post-traumatic symptoms and cognitive outcomes.
-
Randomized Controlled Trial
Umbilical cord mesenchymal stem cell transplantation significantly improves neurological function in patients with sequelae of traumatic brain injury.
The aim of this study was to investigate the effects of transplantation with umbilical cord mesenchymal stem cells in patients with sequelae of traumatic brain injury (TBI). The study hypothesis was that umbilical cord mesenchymal stem cell transplantation could safely and effectively improve neurological function in patients with sequelae of traumatic brain injury. Forty patients with sequelae of TBI were randomly assigned to the stem cell treatment group or the control group. ⋯ All in all, the study results confirmed that the umbilical cord mesenchymal stem cell transplantation improved the neurological function and self-care in patients with TBI sequels. Umbilical cord mesenchymal stem cell transplantation may be a potential treatment for patients with sequelae of TBI. Further research, including a multicenter and large sample size prospective randomized clinical trial, will be required to define definitively the role of umbilical cord mesenchymal stem cell transplantation on sequelae of TBI.
-
Randomized Controlled Trial
Effects of trauma, hemorrhage and resuscitation in aged rats.
Traumatic brain injury (TBI) is a leading cause of death in the elderly and the incidence of mortality and morbidity increases with age. This study tested the hypothesis that, after TBI followed by hemorrhagic hypotension (HH) and resuscitation, cerebral blood flow (CBF) would decrease more in aged compared with young rats. Young adult (4-6 months) and aged (20-24 months) male Sprague-Dawley rats were anesthetized with isoflurane, prepared for parasagittal fluid percussion injury (FPI) and randomly assigned to receive either moderate FPI (2.0 atm) only, moderate FPI+severe HH (40 mm Hg for 45 min) followed by return of shed blood, or sham FPI. ⋯ Despite differences in post-resuscitation MAP and CBF, there were no differences in the numbers of FJ-positive neurons in aged compared to young rats after FPI, HH and blood resuscitation. Although cerebral hypoperfusion in the aged rats was not associated with increased hippocampal cell injury, the trauma-induced reductions in CBF and post-resuscitation blood pressure may have resulted in damage to brain regions that were not examined or neurological or behavioral impairments that were not assessed in this study. Therefore, the maintenance of normal blood pressure and cerebral perfusion would be advisable in the treatment of elderly patients after TBI.
-
Randomized Controlled Trial
Temporal changes in cortical activation during distraction from pain: a comparative LORETA study with conditioned pain modulation.
Methods to cognitively distract subjects from pain and experimental paradigms to induce conditioned pain modulation (CPM; formerly termed diffuse noxious inhibitory controls or DNIC) have each highlighted activity changes in closely overlapping cortical areas. This is the first study, to our knowledge, to compare cortical activation changes during these 2 manipulations in the same experimental set-up. Our study sample included thirty healthy young right handed males capable of expressing CPM. ⋯ Both CPM and distraction reduced subjective pain scores to a similar extent. Combining CPM and distraction further reduced pain ratings compared to CPM and distraction alone, supporting the dissimilarity of the mechanisms of pain modulation under these 2 manipulations. The results are discussed in terms of the differential functional roles of the prefrontal cortex.
-
Randomized Controlled Trial
Brain polarization of parietal cortex augments training-induced improvement of visual exploratory and attentional skills.
Recent evidence suggests that behavioural gains induced by behavioural training are maximized when combined with techniques of cortical neuromodulation, such as transcranial Direct Current Stimulation (tDCS). Here we address the validity of this appealing approach by investigating the effect of coupling a multisensory visual field exploration training with tDCS of the posterior parietal cortex (PPC). The multisensory visual field exploration training consisted in the practice of visual search through the systematic audio-visual stimulation of the visual field. ⋯ In addition, right PPC tDCS brings about an improvement of covert visual orienting, in a task different from the visual search practice. In an additional experiment, we confirm that right parietal tDCS by itself, even without the associated training, can lead to enhancement of visual search. Overall, anodal PPC tDCS is a promising technique to enhance visuo-spatial abilities, when combined to a visual field exploration training task.