We investigated whether turning problems in Parkinson's disease may be the result of abnormal horizontal multisegmental angular coordination. Ten mildly affected patients and controls stood upright and voluntarily reoriented eyes and body to illuminated targets of eccentricities up to ±180 degrees. The effects of target location, visibility, and predictability on movement parameters were evaluated. Patients' latencies were normal. Control subjects foveated large eccentricity targets with a single gaze shift in approximately 30% of predictable trials. Patients rarely did so (10% of predictable trials) because of reduced head-in-space and trunk velocity. This resulted in massive foveation delays in patients-an average of half a second for displacements of 180 degrees. The covariation of eye, head, and trunk rotations was quantified statistically by means of principal components analysis. In both groups, the combined movement was initially stereotyped and two principal components accounted for nearly all data variance-the original three mechanical degrees of freedom (i.e., eye-head-trunk) are reduced to two kinematic degrees of freedom. However, in patients, the eye contributed more, and the head and trunk less, to the gaze shift than in control subjects. Although the eye-to-foot turning synergy is preserved in early-stage parkinsonism, quantitative differences are prominent, particularly a larger ocular (and smaller head-trunk) contribution in patients. Turning problems in Parkinson's disease do not result from inability to assemble multisegmental movements, as patients' ability to control numerous degrees of freedom is preserved. However, trunk bradykinesia reduces the frequency of single-step gaze shifts, thus prolonging target acquisition time. Preserved eye motion compensates for trunk slowness.

No abstract

Climate change is one of the most pressing threats facing humanity in our times. Understanding public perceptions of climate change and its risks is the key to any mitigation and adaptation initiatives. Previous works discussed the influence of experiencing climate-related disasters, as well as the role of environmental sensitivity, but also acknowledged important regional variations, gaps and uncertainties. This work focuses on examining the relationship between personal disaster experience, risk perceptions of climate change and ideology with respect to the environment using the New Ecological Paradigm. The study exploits the results of a questionnaire survey in Greece, a characteristic example of the multihazard region of the Eastern Mediterranean. Results show that both direct disaster experience and a person’s views on the causes of recent disasters in the country are connected with environmental sensitivity and climate change risk perception in a positive way. Both factors are also correlated with views on the effects of climate change. The findings are in agreement with research outcomes in other areas of the world, showing the importance of disaster experience and the views on extreme events in influencing perceptions of climate change. The work contributes to the growing literature on risk perception of climate change and the role of natural hazards, by adding a new piece in the knowledge puzzle in the climate-sensitive and relatively data-poor region of the Eastern Mediterranean.

No abstract

No abstract