Demonstration of nondeclarative sequence learning in mice: development of an animal analog of the human serial reaction time task

In this paper, we demonstrate nondeclarative sequence learning in mice using an animal analog of the human serial reaction time task (SRT) that uses a within-group comparison of behavior in response to a repeating sequence versus a random sequence. Ten female B6CBA mice performed eleven 96-trial sessions containing 24 repetitions of a 4-trial sequence. During the 12th session, the repeating sequence was replaced with the random sequence halfway through the session. Reaction time (RT) to respond to an illuminated nose-poke was recorded, and performance was compared at the halfway point in each session to test for any change in behavior. For learning effect, RTs decreased over the no-switch repeating-sequence sessions. For interference effect, behavior did not change appreciably at the halfway point during the last repeating-sequence session. However, RTs deteriorated significantly after the switch from repeating to random sequences halfway through session 12. The mice demonstrated a robust interference effect when switched from repeating to random sequences. This pattern of behavior in humans performing the SRT is interpreted as evidence of nondeclarative sequence learning. The similarity between the human and mouse SRTs will enable more direct comparisons of mouse-human nondeclarative memory behavior and will provide a useful behavioral end-point in mouse-models of basal ganglia dysfunction.     

What, if anything, is the medial temporal lobe, and how can the amygdala be part of it if there is no such thing?

Should the medial temporal lobe (MTL) of primates--which includes allocortical structures such as the hippocampus, neocortical structures such as the parahippocampal cortex, and nuclear structures such as the basolateral amygdala--be considered a single "thing"? According to the prevailing view, here termed the reification theory, the answer is yes. According to this theory, the MTL functions as an amalgamated entity that provides the neuronal mechanisms for declarative memory; the greater the damage to the MTL or any of its components, the greater the deleterious effects on declarative memory. A countervailing view, here called the balkanization theory, holds that the various components of the MTL process and store different kinds of information. According to this theory, damage to each part of the MTL causes a unique set of behavioral deficits-some involving memory, others involving perception, and yet others involving response selection. The empirical neuropsychological evidence favors the balkanization theory, as do some new concepts in theoretical neuroanatomy.     

<Emphasis Type="Italic">Commentary</Emphasis>: Implementing Empirically Supported Treatments in the Schools: What Are We Asking?

The research reported in this special issue addresses important areas for the continued development of empirically supported school-based treatments. Although advances in the development and evaluation of treatment services have occurred, there is little public demand for the widespread dissemination of these treatments. In this commentary, the authors draw data from historical examples, related research, and personal experience to demonstrate the need to create a societal mandate for change. They present specific implications for future areas of research and the type of public education and marketing campaign that will be needed to create a demand for empirically supported school-based treatments.     

Speech and sensibility: Levinas and Habermas on the constitution of the moral point of view

For Habermas, a moral point of view is based in the procedural requirements of our linguistic competence. For Levinas, it is the way in which we find ourselves related in speech to the face of the other that we find ourselves obliged to the other. But these differing conceptions of the moral significance of language need not be seen as opposed to each other. Rather, they can be conceptualized as complimentary accounts of the ways in which a moral point of view onto life is inextricably bound up for us with our capacities as linguistic creatures. While Habermas enables us to see the importance of language as a rule-governed social practice for the constitution of a moral point of view, Levinas draws our attention to the way in which the moral significance of language so conceived lies in a form of sensibility, a sensible “exposure” or “vulnerability” to the other person, older than language itself. Appropriately coordinated, these two perspectives give us a more adequate understanding than either can on its own of the central place of language in our lives as moral agents.     

Convergence of biological and psychological perspectives on cognitive coordination in schizophrenia

The concept of locally specialized functions dominates research on higher brain function and its disorders. Locally specialized functions must be complemented by processes that coordinate those functions, however, and impairment of coordinating processes may be central to some psychotic conditions. Evidence for processes that coordinate activity is provided by neurobiological and psychological studies of contextual disambiguation and dynamic grouping. Mechanisms by which this important class of cognitive functions could be achieved include those long-range connections within and between cortical regions that activate synaptic channels via NMDA-receptors, and which control gain through their voltage-dependent mode of operation. An impairment of these mechanisms is central to PCP-psychosis, and the cognitive capabilities that they could provide are impaired in some forms of schizophrenia. We conclude that impaired cognitive coordination due to reduced ion flow through NMDA-channels is involved in schizophrenia, and we suggest that it may also be involved in other disorders. This perspective suggests several ways in which further research could enhance our understanding of cognitive coordination, its neural basis, and its relevance to psychopathology.     

A four-component model of procedural justice: defining the meaning of a "fair" process

Two studies test the prediction of the four-component model of procedural justice that people evaluate the fairness of group procedures using four distinct types of judgment. The model hypothesizes that people are influenced by two aspects of the formal procedures of the group: those aspects that relate to decision making and those that relate to the quality of treatment that group members are entitled to receive under the rules. In addition, people are hypothesized to be separately influenced by two aspects of the authorities with whom they personally deal: the quality of decision making by those authorities and the quality of the treatment that they receive from them. The results of two studies support the hypothesis of the four-component model by finding that all four of the procedural judgments identified by the model contribute to overall evaluations of the fairness of group procedures.     

Stressor exposure produces long-term reductions in antigen-specific T and B cell responses

Exposure to an acute laboratory stressor at the time of keyhole limpet hemocyanin (KLH) immunization results in a long-term suppression in circulating anti-KLH antibody. The mechanism for the stress-induced reduction in anti-KLH immunoglobulin (Ig) remains unknown. Given that the generation of anti-KLH antibody requires T cell help, we hypothesize that stress reduces the proliferation of anti-KLH T cells, thus leading to a reduction in anti-KLH antibody. The present studies examined the effect of tail shock stress (100, 1.6 mA, 5-s, 60 s ITI) on the KLH specific T cell response. Fischer F344 rats were immunized either intraperitoneally (i.p.) or subcutaneously (s.c.) at the base of the tail with 200 microg KLH, and exposed to inescapable tail shock (IS) or remained in their home cages (HCC). T cell proliferation after KLH restimulation, but not ConA, was markedly suppressed in IS animals in both the spleen after i.p. immunization and the draining lymph nodes after s.c. immunization. Other secondary lymphoid cells did not differ in their proliferative capacity. Anti-KLH IgG, IgG1 and IgG2a, but not anti-KLH IgM serum levels were significantly suppressed. These data support the conclusion that stress suppresses the generation of antigen specific T cells. In addition, the methods employed in the current study allow the isolation of the site of the acquired T cell immune response, making it possible to further elucidate the cellular mechanisms that contribute to stress-induced modulation of the antigen-specific acquired immune response.     

Trauma: the seductive hypothesis

In much of contemporary culture, "trauma" signifies not so much terrible experience as a particular context for understanding and responding to a terrible experience. In therapy, in the media, and in international interventions, the traumatized are seen not simply as people who suffer and so are deserving of concern and aid; they are seen also as people who suffer for us, who are given special dispensation. They are treated with awe if they tell a certain kind of trauma story, and are ignored or vilified if they tell another. Trauma has become not simply a story of pain and its treatment, but a host of sub-stories involving the commodification of altruism, the justification of violence and revenge, the entry point into "true experience," and the place where voyeurism and witnessing intersect. Trauma is today the stuff not only of suffering but of fantasy. Historically, trauma theory and treatment have shown a tension, exemplified in the writings of Freud and Janet, between those who view trauma as formative and those who view it as exceptional. The latter view, that trauma confers exceptional status deserving of special privilege, has gained ground in recent years and has helped to shape the way charitable dollars are distributed, how the traumatized are presented in the media, how governments justify and carry out international responses to trauma, and how therapists attend to their traumatized patients. This response to trauma reflects an underlying, unarticulated belief system derived from narcissism; indeed, trauma has increasingly become the venue, in society and in treatment, where narcissism is permitted to prevail.     

Adult attachment,the transition to parenthood,and depressive symptoms

Testing a model suggested by J. Bowlby (1988), this study investigated how a personal vulnerability (attachment ambivalence) interacts with perceptions of deficient spousal support before and during a major life stressor (the transition to parenthood) to predict pre-to-postnatal increases in depressive symptoms. Highly ambivalent women who entered parenthood perceiving either less support or greater anger from their husbands experienced pre-to-postnatal increases in depressive symptoms at 6 months postpartum. The associations between these 2 prenatal interaction terms and pre-to-postnatal increases in depressive symptoms were mediated by perceptions of declining spousal support across the transition period. Moreover, for highly ambivalent women, the association between prenatal and postnatal depression scores was mediated by perceptions of the amount of support available from their husbands.     

Bimanual cross-talk during reaching movements is primarily related to response selection,not the specification of motor parameters

Simultaneous reaching movements made with the two hands can show a considerable increase in reaction time (RT) when they differ in terms of direction or extent, compared to when the movements involve the same direction and extent. This cost has been attributed to cross-talk in the specification of the motor parameters for the two hands. However, a recent study [Diedrichsen, Hazeltine, Kennerley, & Ivry, (2001). Psychological Science, 12, 493-498] indicates that when reaching movements are cued by the onset of the target endpoint, no compatibility effects are observed. To determine why directly cued movements are immune from interference, we varied the stimulus onset asynchrony for the two movements and used different combinations of directly cued and symbolically cued movements. In two experiments, compatibility effects were only observed when both movements were symbolically cued. No difference was found between compatible and incompatible movements when both movements were directly cued or when one was directly cued and the other was symbolically cued. These results indicate that interference is not related to the specification of movement parameters but instead emerges from processes associated with response selection. Moreover, the data suggest that cross-talk, when present, primarily shortens the RT of the second movement on compatible trials rather than lengthening this RT on incompatible trials.