On trend estimation under monotone Gaussian subordination with long-memory: application to fossil pollen series

Fossil pollen data from stratigraphic cores are irregularly spaced in time due to non-linear age-depth relations. Moreover, their marginal distributions may vary over time. We address these features in a nonparametric regression model with errors that are monotone transformations of a latent continuous-time Gaussian process Z(T). Although Z(T) is unobserved, due to monotonicity, under suitable regularity conditions, it can be recovered facilitating further computations such as estimation of the long-memory parameter and the Hermite coefficients. The estimation of Z(T) itself involves estimation of the marginal distribution function of the regression errors. These issues are considered in proposing a plug-in algorithm for optimal bandwidth selection and construction of confidence bands for the trend function. Some high-resolution time series of pollen records from Lago di Origlio in Switzerland, which go back ca. 20,000 years are used to illustrate the methods.

Eluding oblivion with smart stochastic selection of synaptic updates

The variables involved in the equations that describe realistic synaptic dynamics always vary in a limited range. Their boundedness makes the synapses forgetful, not for the mere passage of time, but because new experiences overwrite old memories. The forgetting rate depends on how many synapses are modified by each new experience: many changes means fast learning and fast forgetting, whereas few changes means slow learning and long memory retention. Reducing the average number of modified synapses can extend the memory span at the price of a reduced amount of information stored when a new experience is memorized. Every trick which allows to slow down the learning process in a smart way can improve the memory performance. We review some of the tricks that allow to elude fast forgetting (oblivion). They are based on the stochastic selection of the synapses whose modifications are actually consolidated following each new experience. In practice only a randomly selected, small fraction of the synapses eligible for an update are actually modified. This allows to acquire the amount of information necessary to retrieve the memory without compromising the retention of old experiences. The fraction of modified synapses can be further reduced in a smart way by changing synapses only when it is really necessary, i.e. when the post-synaptic neuron does not respond as desired. Finally we show that such a stochastic selection emerges naturally from spike driven synaptic dynamics which read noisy pre and post-synaptic neural activities. These activities can actually be generated by a chaotic system.

Predictors of depressed mood 12 months after injury. Contribution of self-efficacy and social support

Abstract Purpose: There is evidence that depressed mood and perception of pain are related in patients with chronic illness. However, how individual resources such as self-efficacy and social support play a role in this association remains unclear. The aim of this study was to investigate the influence of both variables as either moderator or mediator. Method: In a longitudinal study, 274 injured workers (M = 43.24 years) were investigated. Data were collected on sociodemographics, depressed mood, pain, social support, and self-efficacy at three months post-injury, and depressed mood one year post-injury. Results: Hierarchical multiple linear regression analyses revealed that pain (β = 0.14; p < 0.01) and social support (β = -0.18; p < 0.001) were significant predictors of depressed mood. Self-efficacy moderated the relationship of pain (β = -0.12; p < 0.05) and depressed mood after one year. Lower self-efficacy in combination with pain had a stronger impact than higher self-efficacy and pain on depressed mood. Social support did not moderate the association. Conclusions: Self-efficacy for managing pain is important in the development of depressed mood. According to the results of this study, we suggest that the detection of low social support and low self-efficacy might be important in long-term rehabilitation process. Implications for Rehabilitation Risk for depressed mood one year after an accident is high: One in five workers report depressed mood. Protective factors for depressed mood in injured workers needs to be considered in the rehabilitation. Focusing on resources like social support and self-efficacy could be protective against depressed mood. The early detection of low social support and low self-efficacy might be important in long-term rehabilitation processes

Motive-Oriented Psychotherapeutic Relationship Facing a Patient Presenting with Narcissistic Personality Disorder: A Case Study

Motive-oriented therapeutic relationship (MOTHER), a prescriptive concept based on an integrative form of case formulation, the Plan Analysis (PA) method (Caspar, in: Eells (ed.), Handbook of psychotherapy case formulations, 2007), has shown to be of particular relevance for the treatment of patients presenting with personality disorders, in particular contributing to better therapeutic outcome and to a more constructive development of the therapeutic alliance over time (Kramer et al., J Nerv Ment Dis 199:244–250, 2011). Several therapy models refer to MOTHER as intervention principle with regard to borderline and Narcissistic Personality Disorder (NPD) (Sachse et al., Clarification-oriented psychotherapy of narcissistic personality disorder, 2011; Caspar and Berger, in: Dulz et al. (eds.), Handbuch der Borderline-Störungen, 2011). The present case study discusses the case of Mark, a 40-year-old patient presenting with NPD, along with anxious, depressive and anger problems. This patient underwent a seven-session long pre-therapy process, based on psychiatric and psychotherapeutic principles complemented with PA and MOTHER, in preparation for further treatment. MOTHER will be illustrated with patient–therapist verbatim from session 4 and the links between MOTHER and confrontation techniques will be discussed in the context of process-outcome hypotheses, in particular the effect of MOTHER on symptom reduction.

Optimal Confidence Bands for Shape-Restricted Curves

Let Y be a stochastic process on [0,1] satisfying dY(t)=n 1/2 f(t)dt+dW(t) , where n≥1 is a given scale parameter (`sample size'), W is standard Brownian motion and f is an unknown function. Utilizing suitable multiscale tests, we construct confidence bands for f with guaranteed given coverage probability, assuming that f is isotonic or convex. These confidence bands are computationally feasible and shown to be asymptotically sharp optimal in an appropriate sense.

Memory of childbirth in the second year: the long-term effect of a negative birth experience and its modulation by the perceived intranatal relationship with caregivers

OBJECTIVE: To assess the memory of various subdimensions of the birth experience in the second year postpartum, and to identify women in the first weeks postpartum at risk of developing a long-term negative memory. DESIGN, METHOD, OUTCOME MEASURES: New mothers' birth experience (BE) was assessed 48-96 hours postpartum (T1) by means of the SIL-Ger and the BBCI (perception of intranatal relationships); early postnatal adjustment (week 3 pp: T1(bis)) was also assessed. Then, four subgroups of women were defined by means of a cluster-analysis, integrating the T1/T1(bis) variables. To evaluate the memory of the BE, the SIL-Ger was again applied in the second year after childbirth (T2). First, the ratings of the SIL-Ger dimensions of T1 were compared to those at T2 in the whole sample. Then, the four subgroups were compared with respect to their ratings of the birth experience at T2 (correlations, ANOVAs and t-tests). RESULTS: In general, fulfillment, emotional adaptation, physical discomfort, and anxiety improve spontaneously over the first year postpartum, whereas in negative emotional experience, control, and time-going-slowly no shift over time is observed. However, women with a negative overall birth experience and a low level of perceived intranatal relationship at T1 run a high risk of retaining a negative memory in all of the seven subdimensions of the birth experience. CONCLUSIONS: Women at risk of developing a negative long-term memory of the BE can be identified at the time of early postpartum, when the overall birth experience and the perceived intranatal relationship are taken into account.

Information processing in long delay memory-guided saccades: further insights from TMS

The performance of memory-guided saccades with two different delays (3 s and 30 s of memorisation) was studied in eight subjects. Single pulse transcranial magnetic stimulation (TMS) was applied simultaneously over the left and right dorsolateral prefrontal cortex (DLPFC) 1 s after target presentation. In both delays, stimulation significantly increased the percentage of error in amplitude of memory-guided saccades. Furthermore, the interfering effect of TMS was significantly higher in the short delay compared to that of the long delay paradigm. The results are discussed in the context of a mixed model of spatial working memory control including two components: First, serial information processing with a predominant role of the DLPFC during the early period of memorisation and, second, parallel information processing, which is independent from the DLPFC, operating during longer delays.

Long-Term outcome in patients with mild traumatic brain injury: A prospective observational study

Mild traumatic brain injury (MTBI) is common; up to 37% of adult men have a history of MTBI. Complaints after MTBI are persistent headaches, memory impairment, depressive mood disorders, and disability. The reported short- and long-term outcomes of patients with MTBI have been inconsistent. We have now investigated long-term clinical and neurocognitive outcomes in patients with MTBI (at admission, and after 1 and 10 years).

Dopaminergic modulation of rapid reality adaptation in thinking

Dopamine has long held a prominent role in the interpretation of schizophrenia and other psychoses. Clinical studies on confabulation and disorientation, disorders marked by a confusion of reality in thinking, indicated that the ability to keep thinking in phase with reality depends on a process suppressing the interference of upcoming memories that do not refer to ongoing reality. A host of animal studies and a recent clinical study suggested that this suppression might correspond to the phasic inhibition of dopaminergic neurons in response to the absence of expected outcomes. In this study, we tested healthy subjects with a difficult version of a memory paradigm on which confabulating patients had failed. Subjects participated in three test sessions, in which they received in double-blind, randomized fashion L-dopa, risperidone, or placebo. We found that l-dopa, in comparison with risperidone, impaired performance in a highly specific way, which corresponded to the pattern of patients with reality confusion. Specifically, they had an increase of false positive responses, while overall memory performance and reaction times were unaffected. We conclude that dopaminergic transmission influences the ability to rapidly adapt thinking to ongoing reality.

Structural aspects of redox-mediated electron tunneling (Dedicated to the memory of professor Alexander M. Kuznetsov)

We investigated structural aspects of electron transfer (ET) in tunneling junctions (Au(1 1 1)vertical bar FcN vertical bar solution gap vertical bar Au STM tip) with four different redox-active N-thioalk(ano)ylferrocenes (FcN) embedded. The investigated molecules consist of a redox-active ferrocene (Fc) moiety connected via alkyl spacers with N = 4, 6, 8 and 11 carbon atoms to a thiol anchoring group. We found that for short FcNs (N = 4, 6,8) the redox-mediated ET response increases with the increase of the alkyl chain length, while no enhancement of the ET was observed for Fc1 1. The model of two-step ET with partial vibrational relaxation by Kuznetsov and Ulstrup was used to rationalize these results. The theoretical ET steps were assigned to two processes: (1) electron tunneling from the Fc group to the Au tip through the electrolyte layer and (2) electron transport from the Au(1 1 1) substrate to the Fc group through the organic adlayer. We argue that for the three short FcNs, the first process represents the rate-limiting step. The increase of the length of the alkyl chain leads to an approach of the Fc group to the STM tip, and consequently accelerates the first El' step. In case of the Fcl 1 junctions the rather high thickness of the organic layer leads to a decrease of the rate of the second ET step. In consequence, the contribution of the redox-mediated current enhancement to the total tunneling current appears to be insignificant. Our work demonstrates the importance of combined structural and transport approaches for the understanding of Er processes in electrochemical nanosystems. (C) 2010 Elsevier B.V. All rights reserved.