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Objective Indices (objective + index)
Selected AbstractsAmygdala,prefrontal dissociation of subliminal and supraliminal fearHUMAN BRAIN MAPPING, Issue 8 2006Leanne M. Williams Abstract Facial expressions of fear are universally recognized signals of potential threat. Humans may have evolved specialized neural systems for responding to fear in the absence of conscious stimulus detection. We used functional neuroimaging to establish whether the amygdala and the medial prefrontal regions to which it projects are engaged by subliminal fearful faces and whether responses to subliminal fear are distinguished from those to supraliminal fear. We also examined the time course of amygdala-medial prefrontal responses to supraliminal and subliminal fear. Stimuli were fearful and neutral baseline faces, presented under subliminal (16.7 ms and masked) or supraliminal (500 ms) conditions. Skin conductance responses (SCRs) were recorded simultaneously as an objective index of fear perception. SPM2 was used to undertake search region-of-interest (ROI) analyses for the amygdala and medial prefrontal (including anterior cingulate) cortex, and complementary whole-brain analyses. Time series data were extracted from ROIs to examine activity across early versus late phases of the experiment. SCRs and amygdala activity were enhanced in response to both subliminal and supraliminal fear perception. Time series analysis showed a trend toward greater right amygdala responses to subliminal fear, but left-sided responses to supraliminal fear. Cortically, subliminal fear was distinguished by right ventral anterior cingulate activity and supraliminal fear by dorsal anterior cingulate and medial prefrontal activity. Although subcortical amygdala activity was relatively persistent for subliminal fear, supraliminal fear showed more sustained cortical activity. The findings suggest that preverbal processing of fear may occur via a direct rostral,ventral amygdala pathway without the need for conscious surveillance, whereas elaboration of consciously attended signals of fear may rely on higher-order processing within a dorsal cortico,amygdala pathway. Hum Brain Mapp, 2005. © 2005 Wiley-Liss, Inc. [source] Soil conservation in Polylepis mountain forests of Central Argentina: Is livestock reducing our natural capital?AUSTRAL ECOLOGY, Issue 4 2010DANIEL RENISON Abstract Mountain forests and their soils provide ecological services such as maintenance of biodiversity, provision of clean water, carbon capture and forage for livestock rearing, which is one of the principal economic activities in mountain areas. However, surprisingly little is known about livestock impact in South American mountain forest soils. With the aim of understanding how livestock and topography influence patterns of forest cover, soil compaction, soil loss and soil chemical properties, we analysed these parameters in 100 Polylepis australis woodland plots situated in the humid subtropical mountains of Central Argentina. We used distance from the nearest ranch as an objective index of historical livestock impact and measured standard topographic variables. Our main results reveal that distance from ranch in all cases partly explains tree canopy cover, soil loss, soil compaction and soil chemical properties; suggesting a strong negative effect of livestock. Intermediate altitudes had more tree canopy cover, while landscape roughness , a measure of the variability in slope inclination and aspect , was negatively associated to soil impedance and acidity, and positively associated to soil organic matter content. Finally, flatter areas were more acid. We conclude that livestock has had a substantial influence on forest soil degradation in the Mountains of Central Argentina and possibly other similar South American mountains. Soil degradation should be incorporated into decision making when considering long-term forest sustainability, or when taking into account retaining livestock for biodiversity conservation reasons. Where soil loss and degradation are ongoing, we recommend drastic reductions in livestock density. [source] Threshold electrical stimulation (TES) in ambulant children with CP: a randomized double-blind placebo-controlled clinical trialDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 6 2002Christineí Dali MD A randomized double-blind placebo-controlled clinical trial was carried out to determine whether a group of stable children with cerebral palsy (36 males, 21 females; mean age 10 years 11 months, range 5 to 18 years) would improve their motor skills after 12 months of threshold electrical stimulation (TES). Two thirds received active and one third received inactive stimulators. For the primary outcome we constructed a set of plausible motor function tests and studied the change in summary indices of the performance measurements. Tests were videotaped and assessed blindly to record qualitative changes that might not be reflected in performance measurements. We also judged range of motion, degree of spasticity, and muscle growth measured by CT. Fifty seven of 82 outpatients who were able to walk at least with a walker, completed all 12 months of treatment (hemiplegia n=25, diplegia n=32). There was no significant difference between active and placebo treatment in any of the tested groups, nor combined. Visual and subjective assessments favoured TES (ns), whereas objective indices showed the opposite trend. We conclude that TES in these patients did not have any significant clinical effect during the test period. [source] The Emotional Climate of Nations and Their Culture of PeaceJOURNAL OF SOCIAL ISSUES, Issue 2 2007Joseph De Rivera Societies seem to have emotional climates that affect how people feel and act in public situations. Unlike the emotions experienced in an individual's personal life, these modal feelings reflect a collective response to the socio-economic-political situation of the society and influence how most people behave toward one another and their government. A government may foster a climate of fear to ensure social control, or it may encourage the formation of heterogeneous social groups to facilitate a climate of trust between people from different groups. On one hand, emotional climates may be viewed as reflecting the relative peacefulness or violence of a society. Thus, an assessment of emotional climate may provide a subjective index of human security to complement objective measures of democracy, human rights, equality, and other factors that we presume are beneficial to human welfare. On the other hand, we may view emotional climates as influences that act to further or to impede the development of the culture of peace advocated by the General Assembly of the United Nations. Thus, their assessment may have predictive power, and measuring a society's emotional climate may help us to create desirable policy. In this article we show that it is possible to measure some important aspects of the emotional climates of three nations that have different degrees of a culture of peace: Norway, the United States, and India. We show that estimates of the collective emotions that constitute climate can be distinguished from reports of personal emotions in that the former are more influenced by nation and the latter by social class. It is the subjective experience of national emotional climate, rather than personal emotional experience, that appears most related to objective indices for the culture of peace in the different nations. [source] Comparison of hangover effects among triazolam, flunitrazepam and quazepam in healthy subjects: A preliminary reportPSYCHIATRY AND CLINICAL NEUROSCIENCES, Issue 3 2003Taro Takahashi Abstract The aim of the present study was to compare the hangover effects of night-time administration of triazolam (0.25 mg), flunitrazepam (1 mg) and quazepam (15 mg) in healthy subjects. Daytime sleepiness and performance level following the night-time administration of the drugs were assessed using Standford Sleepiness Scale (SSS), Sleep Evaluation Questionnaire (SEQ), Multiple Sleep Latency Test (MSLT), actigraphy recordings and Continuous Performance Test (CPT). Fifteen healthy volunteers were given one of the three hypnotics at each drug session, which lasted for 1 week, in a single-blind cross-over fashion. No significant between-drug difference was observed for the psychomotor performance assessed by CPT. Subjective hangover effects assessed by SSS and SEQ in the morning were prominent for flunitrazepam and quazepam relative to triazolam, whereas objective indices such as MSLT or activity counts obtained in actigraphy indicated a marked hangover effect of quazepam compared with the other two compounds restrictively in the afternoon, which were nearly in accordance with their pharmacokinetic profiles. [source] | |||||||||||||