The Female Professional: Parenting,Career, Choices and Compromises

The American Journal of Psychoanalysis -     

Transitional and steady-state choice behavior under an adjusting-delay schedule

Twelve rats made repeated choices on an adjusting-delay schedule between a smaller reinforcer (A) that was delivered immediately after a response and a larger reinforcer (B) that was delivered after a delay which increased or decreased by 20% depending on the subject's choices in successive blocks of trials. In two phases of the experiment (100 sessions and 40 sessions), reinforcer sizes were selected which enabled theoretical parameters expressing the rate of delay discounting and sensitivity to reinforcer size to be estimated from the ratio of the indifference delays obtained in the two phases. Indifference delays, calculated from adjusting delays in the last 10 sessions of each phase, were shorter when the sizes of A and B were 14 and 25 μl of a 0.6 M sucrose solution than when they were 25 and 100 μl of the same solution. The ratio of the indifference delays was significantly smaller than that predicted on the basis of an assumed linear relation between reinforcer size and instantaneous reinforcer value, consistent with a previous proposal that this relation may be hyperbolic in form. Estimates of the rate of delay discounting based on the ratio of the two indifference delays (mean, 0.08 s(-1)) were similar to values obtained previously using different intertemporal choice protocols. Estimates of the size-sensitivity parameter (mean 113 μl) were similar to estimates recently derived from performance on progressive-ratio schedules. In both phases of the experiment, adjusting delays in successive blocks of trials were analyzed using the Fourier transform. The power spectrum obtained from individual rats had a dominant frequency that corresponded to a period of oscillation of the adjusting delay between 30 and 100 trial blocks (mean, 78). Power in the dominant frequency band was highest in the early sessions of the first phase and declined with extended training. It is suggested that this experimental protocol may have utility in neurobehavioral studies of intertemporal choice.     

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The American Journal of Psychoanalysis -     

‘We Are All the Same,We All Are Mestizos’: Imagined Populations and Nations in Genetics Research in Colombia

In Colombia, as in other Latin American countries, current population genetics research is based on the understanding that Colombians constitute a mestizo nation, given the admixture process that took place between Africans, Amerindians, and Europeans during colonial times. The mestizo is a pervasive category used by geneticists to conduct, organise, and publish research studies that deal with the continent's peopling process and the genetic makeup of its contemporary population(s). It is also the dominant imaginary for the Colombian population and a key nation-building ideology. By tracing how this category moves and is used across four Colombian genetics laboratories, it is possible to discern that despite its apparently clear-cut boundaries, the mestizo is contingent, contested, and flexible, allowing for multiple understandings and usages. This flexibility and multiplicity are visible in the quantification of genetic ancestry, the divisions of geographical location, and the understanding of gender. Such understandings allow one to think about a homogeneous nation (inclusive) that is simultaneously heterogeneous (exclusive); they provide multiple but not necessarily contradictory possibilities of being mestizo, allowing the coexistence of images of the nation that could otherwise seem contradictory; and they permit navigation around contested terms such as race, while simultaneously thinking of mixed races or racialised individuals. Finally, these flexible and multiple constructions of the mestizo (re)produce various subjects as ‘other’, whether they are women, the Indigenous, the black/dark, or the poor.