Naps in school can enhance the duration of declarative memories learned by adolescents

Sleep helps the consolidation of declarative memories in the laboratory, but the pro-mnemonic effect of daytime naps in schools is yet to be fully characterized. While a few studies indicate that sleep can indeed benefit school learning, it remains unclear how best to use it. Here we set out to evaluate the influence of daytime naps on the duration of declarative memories learned in school by students of 10–15 years old. A total of 584 students from 6th grade were investigated. Students within a regular classroom were exposed to a 15-min lecture on new declarative contents, absent from the standard curriculum for this age group. The students were then randomly sorted into nap and non-nap groups. Students in the nap group were conducted to a quiet room with mats, received sleep masks and were invited to sleep. At the same time, students in the non-nap group attended regular school classes given by their usual teacher (Experiment I), or English classes given by another experimenter (Experiment II). These 2 versions of the study differed in a number of ways. In Experiment I (n = 371), students were pre-tested on lecture-related contents before the lecture, were invited to nap for up to 2 h, and after 1, 2, or 5 days received surprise tests with similar content but different wording and question order. In Experiment II (n = 213), students were invited to nap for up to 50 min (duration of a regular class); surprise tests were applied immediately after the lecture, and repeated after 5, 30, or 110 days. Experiment I showed a significant ∼10% gain in test scores for both nap and non-nap groups 1 day after learning, in comparison with pre-test scores. This gain was sustained in the nap group after 2 and 5 days, but in the non-nap group it decayed completely after 5 days. In Experiment II, the nap group showed significantly higher scores than the non-nap group at all times tested, thus precluding specific conclusions. The results suggest that sleep can be used to enhance the duration of memory contents learned in school.

O Plano Diretor como instrumento de gestão da cidade: o caso da cidade de Fortaleza/CE

According to article 182 of the Brazilian Federal Constitution, cities should perform social function, what brings the concept that the city should be a place for one to live well. For that to happen, it should be well administered by its public managers. However, so that there is a sound administration, one that really performs that social function, there must be, first, an efficient planning. We understand that such a thing occurs when the master plan is the main planning instrument of a city and serves as basis for its administration. We notice, however, that in most of the cities the master plan is formulated as a law that regulates urban planning but that both the population and the government most of the times are not aware of its importance concerning the relevant issues related to municipal administration, such as its relationship with the economy, taxation, the social issue, land use regulation, and, in summary, with all the aspects that constitute and that a municipal government should manage in the best possible way. One also knows that, in general, the attempt of city planning has always been connected to the duration of a mandate and that way public managers many times implement restricted measures aiming to just attain a political-electoral objective and publicizing their administration. That implies actions and works that in some cases have negative impacts or ones that cannot be removed from the cities. This study intends to show that the master plan should be the planning instrument guiding the municipal administration but that, however, what we note is a lack of connection between that instrument and the government guidelines of the municipal managers. In order to study what happens to the cities that have a planning which is not taken into account in its administration, we will use the city of Fortaleza, capital of the State of Ceará as a case study. Historically, in Fortaleza the public managers have seldom decided to administer the city in according to the master plans developed for it. We should emphasize that planning begins in the city quite late and until the current days it is being substituted by temporary measures. Through the analysis of the planning process and of the urban management of the city of Fortaleza, especially the master plans predicted since 1933, we explain that if such plans had been implemented, they could have been important tools for its administration to attain a social function, becoming therefore a place for one to live well

Expressão de genes imediatos induzidos por vocalizações em sagüis-comuns (Callithrix jacchus)

Immediate-early genes (IEGs) expression has been widely used as a valuable tool to investigate brain areas activated by specific stimuli. Studies of natural vocalizations, specially in songbirds, have largely benefited from this tool. Here we used IEGs expression to investigate brain areas activated by the hearing of conspecific common marmoset (Callithrix jacchus) vocalizations and/or utterance of antiphonal vocalizations. Nine adult male common marmosets were housed in sound-attenuating cages. Six animals were stimulated with playbacks of freely recorded natural long distance vocalizations (phee calls and twitters; 45 min. total duration). Three of them vocalized in response (O/V group) and three did not (O/n group). The control group (C) was composed by the remaining animals, which neither heard the playbacks nor spontaneously vocalized. After one hour of the stimulation onset (or no stimulation, in the case of the C group), animals were perfused with 0,9% phosphate-saline buffer and 4% paraformaldehyde. The tissue was coronally sectioned at 20 micro meter in a cryostat and submitted to immunohistochemistry for the IEGs egr-1 and c-fos. Marked immunoreactivity was observed in the auditory cortex of O/V and O/n subjects and in the anterior cingulate cortex, the dorsomedial prefrontal cortex and the ventrolateral prefrontal cortex of O/V subjects. In this study, brain areas activated by vocalizations of common marmosets were investigated using IEGs expression for the first time. Our results with the egr-1 gene indicate that potential plastic phenomena occur in areas related to hearing and uttering conspecific vocalizations.