1,721,215 research outputs found
Time-of-day and circadian typology on memory retrieval
No full textThe cognitive functioning varies during the day and it can be modulated by the time in which individuals reach their arousal peak during the day. Morning-types should have cognitive peak in the morning while evening-types should have cognitive peak in the evening, reflecting the synchrony effect. The aim was to investigate time-of-day and synchrony effects on long-term memory with a network-like structure, using semantic classification and number-matching tasks. Evening- and morning-types performed two tasks in three times of the day: morning, afternoon and evening. In semantic classification task, a time-of-day effect was found while synchrony effect did not. Moreover, the circadian typology seemed to modulate the retrieval efficiency from long-term memory. In numbermatching task, no time-of-day as well as synchrony effects were reliable. As before, the circadian typology seemed to influence the retrieval of semantic information. The study may demonstrate that circadian typology seems to differ for the strategies in retrieval information from memory with a network-like structure
Are seasonality of mood and eveningness closely associated?
No full textIt has been suggested that being an bevening typeQ might enhance susceptibility to non-seasonal and seasonal affective
disorders (SAD). In a survey and a prospective study, we examine the relationship between mood seasonality and circadian
typology. In the survey study, the Morningness–Eveningness Questionnaire (MEQ) and the Seasonal Pattern Assessment
Questionnaire (SPAQ) were administered to 1715 university students from Spain and Italy. In the prospective study, 18 subjects, selected from the Italian sample, self-assessed their mood monthly for over a year. A slight but significant negative correlation between the MEQ score and the Global Seasonality Score was found in the survey study, with a significantly higher incidence of evening versus morning types among the students with seasonal depression. These results were not replicated when the Spanish sample was analysed separately. In the prospective study, evening types did not present a higher annual range of mood variations than morning types. Caution should be exercised in ascribing eveningness as a risk factor in SAD since other
underestimated factors, including social–cultural conditions, might be involved in the pathogenesis of mood seasonality
A more accurate assessment of circadian typology is achieved by asking persons to indicate their preferred times rather than comparing themselves with most people
Full text linkThe aim of the present work was to compare two circadian questionnaires: the Preference Scale (PS) and the reduced version of the Morningness-Eveningness Questionnaire (rMEQ). A sample of 849 (35.10% men) university students, 421 of whom were Spanish (27.55% men; mean age 21.07 + 2.31) and 428 Italian (42.52% men; mean age 23.26 + 3.01), were administered both questionnaires. Gender (higher morningness in women) and nationality (higher eveningness in Spaniards) differences were replicated with rMEQ but not with PS, in which an inverse association between nationality and circadian preference was observed (i.e. higher morningness in Spaniards). Taking into account that the formulation of the rMEQ items, with its specific times, makes the answers less influenced by socio-cultural bias, we conclude that rMEQ is preferable to PS when evaluating circadian preference in young adults
On the Radon transform and the Dirac delta distribution in superspace
Full text linkIn this paper, we obtain a plane wave decomposition for the delta distribution in superspace, provided that the superdimension is not odd and negative. This decomposition allows for explicit inversion formulas for the super Radon transform in these cases. Moreover, we prove a more general Radon inversion formula valid for all possible integer values of the superdimension. The proof of this result comes along with the study of fractional powers of the super Laplacian, their fundamental solutions, and the plane wave decompositions of super Riesz kernels
Evaluación mediante "Diagramas V" para un trabajo de integración paleontológica (Escuela de Geología)
Full text linkFil: Mazzoni, Alejandra. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Escuela de Geología. Cátedra y Museo de Paleontología; Argentina.Fil: Tauber, Adan A. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Escuela de Geología. Cátedra y Museo de Paleontología; Argentina.Se analiza la "V de Gowin" como instrumento de evaluación para un trabajo téorico práctico de integración de la Escuela de Geología de la Universidad Nacional de Córdoba.https://app.box.com/s/3cp1uvslr0suf8v50d76Fil: Mazzoni, Alejandra. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Escuela de Geología. Cátedra y Museo de Paleontología; Argentina.Fil: Tauber, Adan A. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Escuela de Geología. Cátedra y Museo de Paleontología; Argentina.Educación General (incluye capacitación, pedagogía y didáctica
Effect of time of day on arithmetic fact retrieval in a number-matching task
No full textThe goal of this study is aimed to investigate a possible effect of time of day on arithmetic fact retrieval in a number-matching task.
We tested 96 students (age range 19–33 years) at 9 a.m. and at 1 p.m., in a counterbalanced order. The subjective alertness levels were
also recorded. As regards retrieval efficiency, the results showed that the sum interference effect was significantly more pronounced in the
morning (9 a.m.) than at midday (1 p.m.). As expected, participants showed higher subjective alertness levels at 1 p.m. than at 9 a.m..
However, the difference of subjective alertness did not completely explain differences in interference at two testing sessions. The results
could be explained with respect to the variation of working memory efficiency during the day
Season of birth, gender, and social-cultural effects on sleep timing preferences in humans
No full textStudy Objective: The present study aimed to analyze season of birth
effects on preferred sleep-wake cycle timing as assessed by Morningness-
Eveningness Questionnaire (MEQ).
Participants and Measurements: The MEQ was administered to a
sample of 5,720 university students (3,851 Italians and 1,869 Spaniards;
3,877 female and 1,843 male; mean age 22.23 ± 2.98 years).
Results: Females preferred to go to bed significantly earlier and sleep
longer than males, regardless of season of birth and nationality. Subjects
born in spring and summer went to bed and reached midpoint of
sleep later than subjects born in fall and winter. Nationality significantly
affected all the sleep parameters considered except duration.
Conclusion: Overall, the effect of the season of birth on sleep preference
timing was significant but quantitatively small. We suggest an
evolutionary context for the different contributions of genetic and environmental
factors in modulating sleep-wake cycles in humans
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Do scales for measuring morningness-eveningness exist all over the world?
No full textMorningness-Eveningness has been theoricized as a continuum along which subjects can be arranged or classified into coarsely determined categories: owls (or Evening-types), intermediate and larks (or Morning-types). This trait is thought to be universal chiefly because it is biologically and genetically determined. The number of categories changes to 5 after adding the “Definitively Evening” and “Definitively Morning” extreme types. This procedure is justified for epidemiological, clinical and research purposes, is common in psychology but raises a number of concerns we shall discuss in this chapter.
To proceed, one first needs some valid instrument: the Morningness-Eveningness Questionnaire is the most widely used scale though others exist that deserve attention. Reliability is a necessary but insufficient property on the road toward validity for a scale’s score. Next, beyond the fact that the common used methods for categorisation are not theoretically sound or equivocal (i.e. for what reasons should we use extreme deciles or extreme quartiles? how are the cut-off scores determined?), the most important criticism is that demographical variables such as age and gender are not taken into consideration. Some recent data emphasize that evening-types are not rare in middle-aged, an erroneous conclusion derived from the rigid categorization. To say it simpler, norms for Morningness scores have not been determined. Moreover, we as others have claimed that cross-cultural validity is a desirable property for scales intended to measure personality traits including Morningness-Eveningness. This property might be extended to the factors extracted in the studied cultures leading to the problem of factorial invariance.
In this chapter, we review the existing scales and their general properties in different cultures before focusing on the problem of categorization with examples showing its limits (e.g. lack of coherence between types determined on different scales). We will eventually propose some remedies. Finally, we will address the issue of cross-gender and cross-cultural factorial invariance of these scales. We conclude that the way is long that will lead to between groups valid comparisons in terms of Morningness-Eveningness scores and/or frequencies of the corresponding types
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