Serum beta-amyloid correlates with neuropsychological impairment

AIMS: Evidence suggests a relationship between peripheral Abeta and AD. We hypothesized that higher levels of serum Abeta(1-42) would be associated with memory impairment, thought to occur early in the disease, and rises in serum Abeta(1-40), which occur later, would be associated with impairment in non-memory measures. METHODS: Using a cross-sectional design, we examined the relationship of serum Abeta(1-40), Abeta(1-42), and the ratio of Abeta(1-42/1-40) to neuropsychological measures in 40 cognitively normal controls, 13 MCI subjects, and 25 AD patients. RESULTS: Serum Abeta(1-42) and the ratio of Abeta(1-42/1-40) were significantly higher in the MCI group compared to the controls. A significant relationship in the hypothesized direction (poorer scores associated with higher Abeta(1-40) serum levels) was found between Abeta(1-40) and measures of executive functions across the entire cohort of individuals tested and with measures of language and processing speed in the AD group. Regression analysis found that neuropsychological measures accounted for 26% of the variance in serum Abeta(1-40,) in the MCI/AD but not the controls. Furthermore that language and executive measures were significant predictors. CONCLUSIONS: Results provide preliminary data to partially support our hypotheses and suggest that changes in serum Abeta levels may be attributed to pathological changes within the brain.     

Attention to faces modulates early face processing during low but not high face discriminability

In the present study, we investigated whether attention to faces results in sensory gain modulation. Participants were cued to attend either to faces or to scenes in superimposed face—scene images for which face discriminability was manipulated parametrically. The face-sensitive N170 event-related potential component was used as a measure of early face processing. Attention to faces modulated N170 amplitude, but only when faces were not highly discriminable. Additionally, directing attention to faces modulated later processing (~230—300 msec) for all discriminability levels. These results demonstrate that attention to faces can modulate perceptual processing of faces at multiple stages of processing, including early sensory levels. Critically, the early attentional benefit is present only when the “face signal” (i.e., the perceptual quality of the face) in the environment is suboptimal.     

Sequential congruency effects in implicit sequence learning

We deal with situations incongruent with our automatic response tendencies much better right after having done so on a previous trial than after having reacted to a congruent trial. The nature of the mechanisms responsible for these sequential congruency effects is currently a hot topic of debate. According to the conflict monitoring model these effects depend on the adjustment of control triggered by the detection of conflict on the preceding situation. We tested whether these conflict monitoring processes can operate implicitly in an implicit learning procedure, modulating the expression of knowledge of which participants are not aware. We reanalyze recently published data, and present an experiment with a probabilistic sequence learning procedure, both showing consistent effects of implicit sequence learning. Despite being implicit, the expression of learning was reduced or completely eliminated right after trials incongruent with the learned sequence, thus showing that sequential congruency effects can be obtained even when the source of congruency itself remains implicit.     

Predicting romantic relationship satisfaction from life history strategy

Attachment style and communication style have been shown in previous research to predict relationship satisfaction. We hypothesized that the ultimate cause underlying the relationship among attachment style, communication style, and relationship satisfaction is Life History Strategy (LHS). Furthermore, we hypothesized that LHS would not only predict relationship satisfaction indirectly through a couple’s attachment style and communication style, but would also predict relationship satisfaction directly. Two structural equation models were constructed to model and test each of these hypotheses. The first showed that the indirect causal pathways from LHS to attachment style, attachment style to communication style, and communication style to relationship satisfaction predicted 16% of the variance in relationship satisfaction. The second added a causal pathway directly from LHS to relationship satisfaction which reduced the estimate for the influence of communication style on relationship satisfaction and increased the total variance predicted in relationship satisfaction to 60%. These results challenge the notion that it is primarily the communication between two romantic partners which influences their relationship outcome by proposing that their LHS may be influential: (1) indirectly through their attachment style and communication style; and (2) directly upon relationship satisfaction.     

Building an Expanded Therapeutic Alliance: A Task Analysis with Families Trapped in Parental-Adolescent Conflict

Parental-adolescent conflict is part of the normal developmental cycle of families, but when it occurs in a dysfunctional way, it is associated with the appearance of various harmful conditions for the family system and for the adolescent in particular. Family therapy is one of the main options for psychotherapeutic intervention in these cases and has ample evidence of its effectiveness. The success of this intervention is conditioned to the construction of an adequate therapeutic alliance with the family, but the process of this task has not been clarified yet. The present study is a task analysis, the purpose of which was to create a heuristic model of how an expanded alliance may be built in these kinds of cases. The model was revised and improved from the intensive analysis of six cases. The resulting model can be a useful guide for family therapists in that it describes the specific client and therapist behaviors involved in balancing the alliance, as well as the potential obstacles and suggested ways to resolve them.     

The asymptotic bias of minimum trace factor analysis, with applications to the greatest lower bound to reliability

In theory, the greatest lower bound (g.l.b.) to reliability is the best possible lower bound to the reliability based on single test administration. Yet the practical use of the g.l.b. has been severely hindered by sampling bias problems. It is well known that the g.l.b. based on small samples (even a sample of one thousand subjects is not generally enough) may severely overestimate the population value, and statistical treatment of the bias has been badly missing. The only results obtained so far are concerned with the asymptotic variance of the g.l.b. and of its numerator (the maximum possible error variance of a test), based on first order derivatives and the asumption of multivariate normality. The present paper extends these results by offering explicit expressions for the second order derivatives. This yields a closed form expression for the asymptotic bias of both the g.l.b. and its numerator, under the assumptions that the rank of the reduced covariance matrix is at or above the Ledermann bound, and that the nonnegativity constraints on the diagonal elements of the matrix of unique variances are inactive. It is also shown that, when the reduced rank is at its highest possible value (i.e., the number of variables minus one), the numerator of the g.l.b. is asymptotically unbiased, and the asymptotic bias of the g.l.b. is negative. The latter results are contrary to common belief, but apply only to cases where the number of variables is small. The asymptotic results are illustrated by numerical examples.This research was supported by grant DMI-9713878 from the National Science Foundation.     

Genealogy of Morality and Law

In order to clarify the relationship between morality and law, it is necessary to define both concepts precisely. Cultural realities refer to concepts which are more specifically defined if we focus towards the genealogy of those realities, that is to say, their motivation, function and aim. Should we start from legal anthropology, comparative law and history of law, law arises as a social technique which coactively imposes ways of solving conflicts, protecting fundamental values for a society's co-existence. Values subject to being protected are proposed by morality, the latter making subordination of law to morality inevitable. This explains that a great number of modern constitutions include a reference to fundamental moral values, that is to say, they have explicitly positivised moral contents. Legal reasoning, at all levels and expressions, needs to appeal to the aforementioned values. Constitutional reasoning, international law, legislative activity and judicial practice are studied to verify the latter. This subordination of law to morality sets out a serious problem: moralities are cultural realities which are only valid for a specific society. In order for law not to fall in a not very rational legal relativism, law should not be subordinated to morality, but to ethics, the latter understood as cross-cultural morality. The Universal Declaration of Human Rights was a step forward in this sense.