Dopaminergic Modulation of Medial Prefrontal Cortex Deactivation in Parkinson Depression.

Parkinson's disease (PD) is associated with emotional abnormalities. Dopaminergic medications ameliorate Parkinsonian motor symptoms, but less is known regarding the impact of dopaminergic agents on affective processing, particularly in depressed PD (dPD) patients. The aim of this study was to examine the effects of dopaminergic pharmacotherapy on brain activation to emotional stimuli in depressed versus nondepressed Parkinson disease (ndPD) patients. Participants included 18 ndPD patients (11 men, 7 women) and 10 dPD patients (7 men, 3 women). Patients viewed photographs of emotional faces during functional MRI. Scans were performed while the patient was taking anti-Parkinson medication and the day after medication had been temporarily discontinued. Results indicate that dopaminergic medications have opposite effects in the prefrontal cortex depending upon depression status. DPD patients show greater deactivation in the ventromedial prefrontal cortex (VMPFC) on dopaminergic medications than off, while ndPD patients show greater deactivation in this region off drugs. The VMPFC is in the default-mode network (DMN). DMN activity is negatively correlated with activity in brain systems used for external visual attention. Thus dopaminergic medications may promote increased attention to external visual stimuli among dPD patients but impede normal suppression of DMN activity during external stimulation among ndPD patients.

Dopaminergic modulation of memory and affective processing in Parkinson depression.

Depression is common in Parkinson's disease and is associated with cognitive impairment. Dopaminergic medications are effective in treating the motor symptoms of Parkinson's disease; however, little is known regarding the effects of dopaminergic pharmacotherapy on cognitive function in depressed Parkinson patients. This study examines the neuropsychological effects of dopaminergic pharmacotherapy in Parkinsonian depression. We compared cognitive function in depressed and non-depressed Parkinson patients at two time-points: following overnight withdrawal and after the usual morning regimen of dopaminergic medications. A total of 28 non-demented, right-handed patients with mild to moderate idiopathic Parkinson's disease participated. Ten of these patients were depressed according to DSM IV criteria. Results revealed a statistically significant interaction between depression and medication status on three measures of verbal memory and a facial affect naming task. In all cases, depressed Parkinson's patients performed significantly more poorly while on dopaminergic medication than while off. The opposite pattern emerged for the non-depressed Parkinson's group. The administration of dopaminergic medication to depressed Parkinson patients may carry unintended risks.

Does emotional memory enhancement assist the memory-impaired?

We review recent work on emotional memory enhancement in older adults and patients with mild cognitive impairment (MCI) or Alzheimer dementia (AD) and evaluate the viability of incorporating emotional components into cognitive rehabilitation for these groups. First, we identify converging evidence regarding the effects of emotional valence on working memory in healthy aging. Second, we introduce work that suggests a more complex role for emotional memory enhancement in aging and identify a model capable of unifying disparate research findings. Third, we survey the neuroimaging literature for evidence of a special role for the amygdala in MCI and early AD in emotional memory enhancement. Finally, we assess the theoretical feasibility of incorporating emotional content into cognitive rehabilitation given all available evidence.

Emotion recognition and marital satisfaction in stroke.

Deficits in the comprehension of facial and prosodic expressions are commonly associated with right hemisphere stroke. However, little is known regarding the impact of these disorders on social relations. We examined facial and prosodic processing, mood, and marital satisfaction in 12 right hemisphere damaged (RHD) stroke patients and nine controls. Results revealed significant impairments in the comprehension of facial expressions and prosody among RHD stroke patients. Nonparametric correlations in the RHD group showed significant associations between marital satisfaction and facial affect discrimination and matching, and nonaffective prosody discrimination. We conclude that deficits in the recognition of nonverbal expressions are associated with reduced relationship satisfaction.

Emotional dysfunction in Parkinson's disease.

In addition to motor symptomatology, idiopathic Parkinson's disease is characterized by emotional dysfunction. Depression affects some 30 to 40 percent of Parkinson patients and other psychiatric co-morbidities include anxiety and apathy. Neuropsychological and neuroimaging studies of emotional dysfunction in Parkinson patients suggest abnormalities involving mesolimbic and mesocortical dopaminergic pathways. There is also evidence suggesting that the interaction between serotonin and dopamine systems is important in the understanding and treatment of mood disorders in Parkinson's disease. In this review we discuss the neuropsychiatric abnormalities that accompany Parkinson's disease and describe their neuropsychological, neuropharmacologic, and neuroimaging concomitants.

The effects of stroke disability on spousal caregivers.

OBJECTIVE: To examine the effects of unilateral stroke patients' neurobehavioral characteristics on spousal psychosocial function. PARTICIPANTS: The sample consisted of twenty unilateral stroke patients and their spousal caregivers. METHODS: Patient assessments included mood, affect perception, sensorimotor and cognitive function, marital satisfaction, and activities of daily living. Spousal assessments included mood, marital satisfaction, and perceived stress. RESULTS: To avoid the risk of committing a type I error, the alpha-level of 0.05 was corrected for multiple comparisons involving the three outcome measures, resulting in an adjusted alpha of 0.017 (0.05/3). Using this criterion, the negative correlation between patient depression and spousal marital satisfaction was statistically significant (rs=-0.585, p=0.007). There was also a trend for hemispheric side of stroke to correlate with spousal stress (rs=0.498, p=0.025), such that strokes in the left hemisphere were associated with greater stress, whereas strokes in the right hemisphere were associated with less stress. CONCLUSION: These results show that patient depression in particular constitutes a risk factor for marital dissatisfaction in the first few months following stroke. Given that spousal partners provide a large portion of informal support to stroke patients, successful treatment of patient depression may have benefits at the level of the individual, family, and community.

Semantic-phonologic treatment for noun and verb retrieval impairments in aphasia.

Nouns and verbs differ in their neural and psycholinguistic attributes. It is not known whether these differences lead to distinct patterns of response to treatment for individuals with word retrieval impairments associated with aphasia. Eight participants with naming disorders induced by left hemisphere strokes were treated with a semantic-phonologic treatment protocol for nouns and verbs using a single participant multiple baseline design. We measured treatment gains in a picture naming measure and other secondary language and communication measures. Treatment led to improved picture naming for trained nouns and verbs in five of eight patients, with no difference evident between nouns and verbs. Improvements for untrained words were minimal. Improvement in verb retrieval was associated with increases on a functional measure of communicative effectiveness. Improvement for nouns and verbs was associated with severity of word retrieval impairment at onset. Although distinct in neural and psycholinguistic attributes, nouns and verbs were affected by treatment in a similar pattern in this group of individuals. Training-specific effects suggest the need for careful selection of training words to have potential for functional benefit in daily communication.

Affective facial and lexical expression in aprosodic versus aphasic stroke patients.

Past research has shown that lesions in the left cerebral hemisphere often result in aphasia, while lesions in the right hemisphere frequently impair the production of emotional prosody and facial expression. At least 3 processing deficits might account for these affective symptoms: (1) failure to understand the conditions that evoke emotional response; (2) inability to experience emotions; (3) disruption in the capacity to encode non-verbal signals. To better understand these disorders and their underlying mechanisms, we investigated spontaneous affective communication in right hemisphere damaged (RHD) stroke patients with aprosody and left hemisphere damaged (LHD) stroke patients with aphasia. Nine aprosodic RHD patients and 14 aphasic LHD patients participated in a videotaped interview within a larger treatment protocol. Two naïve raters viewed segments of videotape and rated facial expressivity. Verbal affect production was tabulated using specialized software. Results indicated that RHD patients smiled and laughed significantly less than LHD patients. In contrast, RHD patients produced a greater percentage of emotion words relative to total words than did LHD patients. These findings suggest that impairments in emotional prosodic production and facial expressivity associated with RHD are not induced by affective-conceptual deficits or an inability to experience emotions. Rather, they likely represent channel-specific nonverbal encoding abnormalities.

Spontaneous humor among right hemisphere stroke survivors.

We analyzed spontaneous conversational humor production and response among 11 right hemisphere-damaged (RHD) patients, 10 left hemisphere-damaged (LHD) patients, 7 normal controls (NC), and their spouses. RHD patients and their spouses reported a statistically significant decline in the patients' orientation to humor post-stroke. Also, we found a significant positive association between a RHD patient's ability to decode prosody and their self-reported orientation to humor post-stroke.

Regional brain response to faces of humans and dogs.

The extent to which the brain regions associated with face processing are selective for that specific function remains controversial. In addition, little is known regarding the extent to which face-responsive brain regions are selective for human faces. To study regional selectivity of face processing, we used functional magnetic resonance imaging to examine whole brain activation in response to human faces, dog faces, and houses. Fourteen healthy right-handed volunteers participated in a passive viewing, blocked experiment. Results indicate that the lateral fusiform gyrus (Brodmann's area 37) responds maximally to both dog and human faces when compared with other sites, followed by the middle/inferior occipital gyrus (BA 18/19). Sites that were activated by houses versus dog and human faces included the medial fusiform gyrus (BA 19/37), the posterior cingulate (BA 30), and the superior occipital gyrus (BA 19). The only site that displayed significant differences in activation between dog and human faces was the lingual/medial fusiform gyrus. In this site, houses elicited the strongest activation, followed by dog faces, while the response to human faces was negligible and did not differ from fixation. The parahippocampal gyrus/amygdala was the sole site that displayed significant activation to human faces, but not to dog faces or houses.

Functional Outcome Questionnaire for Aphasia: overview and preliminary psychometric evaluation.

OBJECTIVE: To perform a preliminary evaluation of a questionnaire designed to assess functional outcomes of treatment for aphasia. METHODS: The Functional Outcome Questionnaire for Aphasia (FOQ-A) is an inventory consisting of 32 caregiver-completed items rating the person with stroke's ability to perform various communication behaviors on a 5-point scale. The total score for the FOQ-A is reported as a mean of all completed items. The FOQ-A was administered by research assistants to caregivers of patients with left hemisphere stroke (n = 18). RESULTS: The FOQ-A showed acceptable initial reliability and validity properties. As predicted, the FOQ-A displayed high positive correlations with standardized functional communication measures. The FOQ-A also showed only weak associations with other measures (health-related quality of life, caregiver strain). CONCLUSIONS: Overall results of our preliminary psychometric examination of the FOQ-A were promising. The findings suggested that the FOQ-A may be a sensitive measure of functional communication abilities and does not appear to be biased heavily by caregiver strain. Plans for further evaluation of the FOQ-A are discussed.