Neural correlates of musical creativity: differences between high and low creative subjects.

Previous studies of musical creativity suggest that this process involves multi-regional intra and interhemispheric interactions, particularly in the prefrontal cortex. However, the activity of the prefrontal cortex and that of the parieto-temporal regions, seems to depend on the domains of creativity that are evaluated and the task that is performed. In the field of music, only few studies have investigated the brain process of a creative task and none of them have investigated the effect of the level of creativity on the recruit networks. In this work we used magnetic resonance imaging to explore these issues by comparing the brain activities of subjects with higher creative abilities to those with lesser abilities, while the subjects improvised on different rhythmic fragments. We evaluated the products the subjects created during the fMRI scan using two musical parameters: fluidity and flexibility, and classified the subjects according to their punctuation. We examined the relation between brain activity and creativity level. Subjects with higher abilities generated their own creations based on modifications of the original rhythm with little adhesion to it. They showed activation in prefrontal regions of both hemispheres and the right insula. Subjects with lower abilities made only partial changes to the original musical patterns. In these subjects, activation was only observed in left unimodal areas. We demonstrated that the activations of prefrontal and paralimbic areas, such as the insula, are related to creativity level, which is related to a widespread integration of networks that are mainly associated with cognitive, motivational and emotional processes.

Seasonal variation and trends in stroke hospitalizations and mortality in a South American community hospital.

Numerous studies have reported the presence of temporal variations in biological processes. Seasonal variation (SV) in stroke has been widely studied, but little data have been published on this phenomenon in the Southern Hemisphere, and there have been no studies reported from Argentina. The goals of the present study were to describe the SV of admissions and deaths for stroke and examine trends in stroke morbidity and mortality over a 3-year period in a community hospital in Argentina. Hospital discharge reports from the electronic database of vital statistics between 1999 and 2001 were examined retrospectively. Patients who had a main discharge diagnosis of stroke (ischemic or hemorrhagic) or cerebrovascular accident (International Classification of Diseases, Ninth Revision codes 431, 432, 434, and 436) were selected. The study sample included 1382 hospitalizations by stroke (3.5% of all admissions). In-hospital mortality demonstrated a winter peak (25.5% vs 17% in summer; P = .001). The crude seasonal stroke attack rate (ischemic and hemorrhagic) was highest in winter (164 per 100,000 population; 95% CI, 159-169 per 100,000) and lowest in summer (124 per 100,000; 95% CI, 120-127 per 100,000; P = .008). Stroke admissions followed a seasonal pattern, with a winter-spring predominance (P = .008). Our data indicate a clear SV in stroke deaths and admissions in this region of Argentina. The existence of SV in stroke raises a different hypothesis about the rationale of HF admissions and provides information for the organization of care and resource allocation.

Correlation between the Movement Disorders Society Unified Parkinson's Disease rating scale (MDS-UPDRS) and the Unified Parkinson's Disease rating scale (UPDRS) during L-dopa acute challenge.

While Movement Disorders Society Unified Parkinson's Disease rating scale (MDS-UPDRS) validation has been exhaustive; performance evaluation to detect acute changes arising after administration of a single dose of L-dopa has yet to be explored. To determine the correlation between UPDRS and MDS-UPDRS during the acute challenge with Ldopa and the MDS-UPDRS equivalent to 30% cutoff score of UPDRS for defining responsiveness, 64 patients were assessed. Consecutive assessments were performed immediately before and after administration of a single dose of L-dopa/carbidopa 250/25 mg using the motor section of the UPDRS and the MDS-UPDRS. Good diagnostic accuracy, consistent with published findings of high correlation between scales was observed. Area under the curve (AUC) was 0.99 (CI = 0.97-1.00, P < 0.001) and maximum Youden index (Y = 0.905) corresponded to a cutoff of 24.5%. In conclusion we have found an excellent correlation between UPDRS and MDS-UPDRS and that the 30% of variation in UPDRS score used for predicting sustained long term L-dopa response was equivalent to 24% in MDS-UPDRS.

Higher autonomic activation predicts better performance in iowa gambling task.

OBJECTIVE: To evaluate the relationship between the autonomic nervous system basal state and performance in decision-making tasks. BACKGROUND: The link between performance in decision-making tasks and acute changes in autonomic parameters during their execution has been extensively investigated. However, there is lacking evidence regarding the relationship between decision making and basal autonomic state. METHODS: Resting autonomic nervous system activity in 18 healthy individuals was assessed by means of heart rate variability (HRV) analysis before conducting 3 different decision-making tasks: an ambiguous one, the Iowa Gambling Task; a test that assesses risk-taking behavior, the Game of Dice Task; and a test that assesses reversal learning behavior, the Reversal Learning Task. The tasks were administered in a random manner. RESULTS: There was a direct correlation between the Iowa Gambling Task net score and the resting low frequency HRV (r = 0.73; P < 0.001), which is strongly influenced by sympathetic activity. No correlations were found between HRV and the Game of Dice Task net score or the Reversal Learning Task last error trial. CONCLUSIONS: The results are compatible with the idea that a higher basal activation of autonomic nervous system is beneficial for subsequent decision-making process.

The neural substrate of gesture recognition.

Previous studies have linked action recognition with a particular pool of neurons located in the ventral premotor cortex, the posterior parietal cortex and the superior temporal sulcus (the mirror neuron system). However, it is still unclear if transitive and intransitive gestures share the same neural substrates during action-recognition processes. In the present study, we used event-related functional magnetic resonance imaging (fMRI) to assess the cortical areas active during recognition of pantomimed transitive actions, intransitive gestures, and meaningless control actions. Perception of all types of gestures engaged the right pre-supplementary motor area (pre-SMA), and bilaterally in the posterior superior temporal cortex, the posterior parietal cortex, occipitotemporal regions and visual cortices. Activation of the posterior superior temporal sulcus/superior temporal gyrus region was found in both hemispheres during recognition of transitive and intransitive gestures, and in the right hemisphere during the control condition; the middle temporal gyrus showed activation in the left hemisphere when subjects recognized transitive and intransitive gestures; activation of the left inferior parietal lobe and intraparietal sulcus (IPS) was mainly observed in the left hemisphere during recognition of the three conditions. The most striking finding was the greater activation of the left inferior frontal gyrus (IFG) during recognition of intransitive actions. Results show that a similar neural substrate, albeit, with a distinct engagement underlies the cognitive processing of transitive and intransitive gestures recognition. These findings suggest that selective disruptions in these circuits may lead to distinct clinical deficits.