Articles: traumatic-brain-injuries.
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Journal of neurotrauma · Jan 2017
Long-term motor deficits after controlled cortical impact in rats can be detected by fine motor skill tests but not by automated gait analysis.
Animal models with constant, long-lasting motor deficits together with the right tests to assess behavioral abnormalities are needed to study the effectiveness of potential therapies to restore motor functions. In the current study, controlled cortical impact (CCI) was applied in rats to induce damage to the forelimb area of the motor cortex and the dorsal striatum. ⋯ In striking contrast to previous studies on CCI in mice, neither forelimb impairments, nor general changes in gait, were detected with the CatWalk XT. These data suggest that the adhesive removal test, the cylinder test, and the Montoya staircase test are the methods of choice to detect long-term unilateral motor deficits in rats after CCI, whereas the use of automated gait analysis systems might not be suitable to measure these behavioral deviations.
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Journal of neurotrauma · Jan 2017
Greater attention to task-relevant threat due to orbitofrontal lesion.
Injury to the orbitofrontal cortex (OFC) is a frequent consequence of head injury and may lead to dysfunctional regulation of emotional and social behavior. Dysfunctional emotional behavior may partly be related to the role of the OFC in emotion-attention interaction, as reported previously. In order to better understand its role in emotion-attention and emotion-cognitive control interactions, we investigated attention allocation to task-relevant and task-irrelevant threat-related emotional stimuli during a task requiring cognitive control in patients with lesion to the OFC. ⋯ This study provides new evidence for the role of the OFC in emotion-attention and emotion-cognitive control interactions. Further, the OFC seems to contribute to the balance between voluntary and involuntary attention networks in context of emotional stimuli. Better understanding of alterations in emotion-attention interaction offers insight into affective dysfunction due to OFC lesion.
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Journal of neurotrauma · Jan 2017
Combining the antipsychotic drug haloperidol and environmental enrichment after traumatic brain injury is a double-edged sword.
Environmental enrichment (EE) confers significant benefits after experimental traumatic brain injury (TBI). In contrast, the antipsychotic drug (APD) haloperidol (HAL) exerts deleterious effects on neurobehavioral and cognitive recovery. Neurorehabilitation and management of agitation, however, are integral components of the treatment strategy for patients with TBI. ⋯ What was surprising was that the therapeutic effects of EE were greatly reduced by concomitant administration of HAL. No differences in cortical lesion volumes were observed among the groups (p > 0.05). The potential clinical implications of these findings suggest that administering HAL to patients undergoing neurorehabilitation may be a double-edged sword because agitation must be controlled before rehabilitation can be safely initiated and executed, but its use may compromise therapeutic efficacy.
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Journal of neurotrauma · Jan 2017
Unfolded Maps for Quantitative Analysis of Cortical Lesion Location and Extent after Traumatic Brain Injury.
We aimed to generate two-dimensional (2D) unfolded cortical maps from magnetic resonance (MR) images to delineate the location of traumatic brain injury (TBI)-induced cortical damage in functionally diverse cytoarchitectonic areas of the cerebral cortex, and to predict the severity of functional impairment after TBI based on the lesion location and extent. Lateral fluid-percussion injury was induced in adult rats and T2 maps were acquired with magnetic resonance imaging (MRI) at 3 days post-TBI. Somatomotor deficits were assessed based on the composite neuroscore and beam balance test, and spatial learning was assessed in the Morris water maze. ⋯ Subsequent receiver operating characteristic analysis indicated that severity of the MRI lesion in S1ULp and S2 was a sensitive and specific predictor of poor performance in the beam balance test. Moreover, MRI lesions in the S1ULp, S2, S1BF, and Ect and PRh cortices predicted poor performance in the Morris water maze test. Our findings indicate that 2D-unfolded cortical maps generated from MR images delineate the distribution of cortical lesions in functionally different cytoarchitectonic regions, which can be used to predict the TBI-induced functional impairment.
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Journal of neurotrauma · Jan 2017
The therapeutic efficacy of environmental enrichment and methylphenidate alone and in combination after controlled cortical impact injury.
Environmental enrichment (EE) and methylphenidate (MPH) independently confer significant benefit to behavioral recovery after controlled cortical impact (CCI) injury. Given that combinational therapies may be more clinically translatable than monotherapies, the aim of the current study was to test the hypothesis that a combined treatment regimen of EE and MPH would provide greater therapeutic efficacy than either one alone. Anesthetized adult male rats received either a CCI of moderate severity or sham injury and were then randomly assigned to EE or standard (STD) housing where they received either intraperitoneal (ip) MPH (5 mg/kg) or vehicle (VEH; 1.0 mL/kg; ip) beginning 24 h after injury and once daily for 19 days. ⋯ In addition, both EE groups performed significantly better than the TBI+STD+MPH group (p < 0.05), but did not differ from one another (p > 0.05). These data replicate previous findings that both EE and MPH confer cognitive benefits after TBI and extend the findings by revealing that combining EE and MPH does not produce effects greater than either treatment alone, which does not support the hypothesis. The lack of an additive effect may be because of the robustness of the EE.