Early versus delayed surgical treatment in open hand injuries: a paradigm revisited

To date it remains unclear if a delayed surgical treatment of open hand injuries after more than 6 h may be detrimental to outcome. Previous investigations by McLain et al. (J Hand Surg Am 16:108-112, 1980 9), Nylen and Carlsson (Scand J Plast Reconstr Surg 14:185-189, 1991 10) could not find statistical proof of correlation between infection rate and delayed surgical treatment after open hand injuries up to 18 h. The current study was designed to investigate the outcome of early versus delayed surgical treatment after open hand injury.

Orexin receptor antagonism, a new sleep-enabling paradigm: a proof-of-concept clinical trial

The orexin system is a key regulator of sleep and wakefulness. In a multicenter, double-blind, randomized, placebo-controlled, two-way crossover study, 161 primary insomnia patients received either the dual orexin receptor antagonist almorexant, at 400, 200, 100, or 50 mg in consecutive stages, or placebo on treatment nights at 1-week intervals. The primary end point was sleep efficiency (SE) measured by polysomnography; secondary end points were objective latency to persistent sleep (LPS), wake after sleep onset (WASO), safety, and tolerability. Dose-dependent almorexant effects were observed on SE , LPS , and WASO . SE improved significantly after almorexant 400 mg vs. placebo (mean treatment effect 14.4%; P < 0.001). LPS (–18 min (P = 0.02)) and WASO (–54 min (P < 0.001)) decreased significantly at 400 mg vs. placebo. Adverse-event incidence was dose-related. Almorexant consistently and dose-dependently improved sleep variables. The orexin system may offer a new treatment approach for primary insomnia.

Inhibitory control of the human dorsolateral prefrontal cortex during the anti-saccade paradigm--a transcranial magnetic stimulation study

In the anti-saccade paradigm, subjects are instructed not to make a reflexive saccade to an appearing lateral target but to make an intentional saccade to the opposite side instead. The inhibition of reflexive saccade triggering is under the control of the dorsolateral prefrontal cortex (DLPFC). The critical time interval at which this inhibition takes place during the paradigm, however, is not exactly known. In the present study, we used single-pulse transcranial magnetic stimulation (TMS) to interfere with DLPFC function in 15 healthy subjects. TMS was applied over the right DLPFC either 100 ms before the onset of the visual target (i.e. -100 ms), at target onset (i.e. 0 ms) or 100 ms after target onset (i.e. +100 ms). Stimulation 100 ms before target onset significantly increased the percentage of anti-saccade errors to both sides, while stimulation at, or after, target onset had no significant effect. All three stimulation conditions had no significant influence on saccade latency of correct or erroneous anti-saccades. These findings show that the critical time interval at which the DLPFC controls the suppression of a reflexive saccade in the anti-saccade paradigm is before target onset. In addition, the results suggest the view that the triggering of correct anti-saccades is not under direct control of the DLPFC.

Repeated measurements of learned irrelevance by a novel within-subject paradigm in humans

Learned irrelevance (LIrr) refers to the retardation of classical conditioning following preexposure of the to-be-associated stimuli. Healthy volunteers have been tested on three occasions with a new LIrr paradigm avoiding methodological problems which afflict traditional paradigms. A significant LIrr effect was demonstrated on each occasion. Thus, the new paradigm enables repeated measurements of LIrr and might be useful in evaluating long-term effects of medication in psychiatric disorders exhibiting aberrant LIrr.

Using a Prediction and Option Generation Paradigm to Understand Decision Making

In many complex and dynamic domains, the ability to generate and then select the appropriate course of action is based on the decision maker's "reading" of the situation--in other words, their ability to assess the situation and predict how it will evolve over the next few seconds. Current theories regarding option generation during the situation assessment and response phases of decision making offer contrasting views on the cognitive mechanisms that support superior performance. The Recognition-Primed Decision-making model (RPD; Klein, 1989) and Take-The-First heuristic (TTF; Johnson & Raab, 2003) suggest that superior decisions are made by generating few options, and then selecting the first option as the final one. Long-Term Working Memory theory (LTWM; Ericsson & Kintsch, 1995), on the other hand, posits that skilled decision makers construct rich, detailed situation models, and that as a result, skilled performers should have the ability to generate more of the available task-relevant options. The main goal of this dissertation was to use these theories about option generation as a way to further the understanding of how police officers anticipate a perpetrator's actions, and make decisions about how to respond, during dynamic law enforcement situations. An additional goal was to gather information that can be used, in the future, to design training based on the anticipation skills, decision strategies, and processes of experienced officers. Two studies were conducted to achieve these goals. Study 1 identified video-based law enforcement scenarios that could be used to discriminate between experienced and less-experienced police officers, in terms of their ability to anticipate the outcome. The discriminating scenarios were used as the stimuli in Study 2; 23 experienced and 26 less-experienced police officers observed temporally-occluded versions of the scenarios, and then completed assessment and response option-generation tasks. The results provided mixed support for the nature of option generation in these situations. Consistent with RPD and TTF, participants typically selected the first-generated option as their final one, and did so during both the assessment and response phases of decision making. Consistent with LTWM theory, participants--regardless of experience level--generated more task-relevant assessment options than task-irrelevant options. However, an expected interaction between experience level and option-relevance was not observed. Collectively, the two studies provide a deeper understanding of how police officers make decisions in dynamic situations. The methods developed and employed in the studies can be used to investigate anticipation and decision making in other critical domains (e.g., nursing, military). The results are discussed in relation to how they can inform future studies of option-generation performance, and how they could be applied to develop training for law enforcement officers.