Background

and purpose. Mental practice (MP), which involves cognitive rehearsal of physical movements, is a noninvasive, inexpensive method of enabling repetitive, task-specific practice (RTP). Recent, randomized controlled data suggest that MP, when combined with an RTP therapy program, increases affected arm use and function significantly more than RTP only. As a next step, this 10-subject case series examined the possibility that cortical plasticity is a mechanism underlying the treatment effect of MP when combined with RTP.

Method

Ten chronic stroke patients (mean = 36.7 months) exhibiting stable, moderate motor deficits received 30-minute therapy sessions for their affected arms, occurring 3 days/week for 10 weeks, and emphasizing valued activities of daily living (ADLs). Directly after therapy, subjects received 30-minute MP sessions, which required MP of the ADLs performed during therapy. Behavioral outcomes were blindly evaluated using the Action Research Arm Test (ARAT) and the Fugl-Meyer Assessment (FM). Functional magnetic resonance imaging (fMRI) was administered before and after intervention to assess cortical changes.

Results

Before intervention, subjects exhibited stable motor deficits. After intervention, subjects exhibited ARAT and FM score increases (+5.3 and +4.2, respectively) and clinically significant gains in ADLs. Postintervention fMRI revealed significant increases in activation to wrist flexion and extension of the affected hand in the premotor area and primary motor cortex ipsilateral and contralateral to the affected hand, as well as in superior parietal cortex ipsilateral to the affected hand. Decreased activation was noted in parietal cortex of the hemisphere ipsilateral to the affected hand. These changes correlated with anatomical regions in which behavioral changes were observed in the ARAT and FM.

Conclusions

MP is an easy to use, cost-effective strategy that was again shown to improve affected arm outcomes after stroke. This is the first study to demonstrate alteration in the cortical map in response to MP training.

Background

Alcohol dependence (AD) has global effects on brain structure and function, including frontolimbic regions regulating affective processing. Preliminary evidence suggests alcohol blunts limbic response to negative affective stimuli and increases activation to positive affective stimuli. Subtle gender differences are also evident during affective processing.

Methods

Fourteen abstinent AD individuals (8 F, 6 M) and 14 healthy controls (9 F, 5 M), ages 23 to 60, were included in this facial affective processing functional magnetic resonance imaging pilot study. Whole-brain linear regression analyses were performed, and follow-up analyses examined whether AD status significantly predicted depressive symptoms and/or coping.

Results

Fearful Condition-The AD group demonstrated reduced activation in the right medial frontal gyrus, compared with controls. Gender moderated the effects of AD in bilateral inferior frontal gyri. Happy Condition-AD individuals had increased activation in the right thalamus. Gender moderated the effects of AD in the left caudate, right middle frontal gyrus, left paracentral lobule, and right lingual gyrus. Interactive AD and gender effects for fearful and happy faces were such that AD men activated more than control men, but AD women activated less than control women. Enhanced coping was associated with greater activation in right medial frontal gyrus during fearful condition in AD individuals.

Conclusions

Abnormal affective processing in AD may be a marker of alcoholism risk or a consequence of chronic alcoholism. Subtle gender differences were observed, and gender moderated the effects of AD on neural substrates of affective processing. AD individuals with enhanced coping had brain activation patterns more similar to controls. Results help elucidate the effects of alcohol, gender, and their interaction on affective processing.

Background

Scant research has been conducted on neural mechanisms underlying stress processing in individuals with alcohol dependence (AD). We examined neural substrates of stress in AD individuals compared with controls using an fMRI task previously shown to induce stress, assessing amygdala functional connectivity to medial prefrontal cortex (mPFC).

Materials and methods

For this novel pilot study, 10 abstinent AD individuals and 11 controls completed a modified Trier stress task while undergoing fMRI acquisition. The amygdala was used as a seed region for whole-brain seed-based functional connectivity analysis.

Results

After controlling for family-wise error (p = 0.05), there was significantly decreased left and right amygdala connectivity with frontal (specifically mPFC), temporal, parietal, and cerebellar regions. Subjective stress, but not craving, increased from pre-to post-task.

Conclusions

This study demonstrated decreased connectivity between the amygdala and regions important for stress and emotional processing in long-term abstinent individuals with AD. These results suggest aberrant stress processing in individuals with AD even after lengthy periods of abstinence.