The role of syllables in anagram solution: a Rasch analysis.

Anagrams are frequently used by experimental psychologists interested in how the mental lexicon is organized. Until very recently, research has overlooked the importance of syllable structure in solving anagrams and assumed that solution difficulty was mainly due to frequency factors (e.g., bigram statistics). The present study uses Rasch analysis to demonstrate that the number of syllables is a very important factor influencing anagram solution difficulty for both good and poor problem solvers, with polysyllabic words being harder to solve. Furthermore, it suggests that syllable frequency may have an impact on solution times for polysyllabic words, with more frequent syllables being more difficult to solve. The study illustrates the advantages of Rasch analysis for reliable and unidimensional measurement of item difficulty.

A Simulation Toolkit for Testing the Sensitivity and Accuracy of Corticometry Pipelines.

In recent years, the replicability of neuroimaging findings has become an important concern to the research community. Neuroimaging pipelines consist of myriad numerical procedures, which can have a cumulative effect on the accuracy of findings. To address this problem, we propose a method for simulating artificial lesions in the brain in order to estimate the sensitivity and specificity of lesion detection, using different automated corticometry pipelines. We have applied this method to different versions of two widely used neuroimaging pipelines (CIVET and FreeSurfer), in terms of coefficients of variation; sensitivity and specificity of detecting lesions in 4 different regions of interest in the cortex, while introducing variations to the lesion size, the blurring kernel used prior to statistical analyses, and different thickness metrics (in CIVET). These variations are tested in a between-subject design (in two random groups, with and without lesions, using T1-weigted MRIs of 152 individuals from the International Consortium of Brain Mapping (ICBM) dataset) and in a within-subject pre-/post-lesion design [using 21 T1-Weighted MRIs of a single adult individual, scanned in the Infant Brain Imaging Study (IBIS)]. The simulation method is sensitive to partial volume effect and lesion size. Comparisons between pipelines illustrate the ability of this method to uncover differences in sensitivity and specificity of lesion detection. We propose that this method be adopted in the workflow of software development and release.

Change in smoking and drinking after september 11, 2001, in a national sample of ever smokers and ever drinkers.

Telephone survey methodology was used to examine smoking and drinking after the September 11 terrorist attacks in a representative national sample. Most ever smokers and ever drinkers reported no change in substance use after the attacks. Smokers and drinkers who increased substance use were significantly more likely than those who did not to endorse a number of emotional reactions and functional difficulties. The pattern of associations of decreased use with emotional reactions and functional difficulties differed between smokers and drinkers. In general, decreased smoking was associated with denial of emotional reactions and functional difficulties whereas decreased drinking was associated with endorsement of these reactions and difficulties. The results have implications for research, clinical practice, and public health.

Soft palate perforation during orotracheal intubation facilitated by the GlideScope videolaryngoscope.

We report a case in which a videolaryngoscope was used to facilitate endotracheal intubation in a patient with a large exophytic mass involving the right supraglottis. After intubation, it was noted that the soft palate had been perforated by the styletted endotracheal tube. The defect closed spontaneously postoperatively within 9 days.

MINC 2.0: A Flexible Format for Multi-Modal Images.

It is often useful that an imaging data format can afford rich metadata, be flexible, scale to very large file sizes, support multi-modal data, and have strong inbuilt mechanisms for data provenance. Beginning in 1992, MINC was developed as a system for flexible, self-documenting representation of neuroscientific imaging data with arbitrary orientation and dimensionality. The MINC system incorporates three broad components: a file format specification, a programming library, and a growing set of tools. In the early 2000's the MINC developers created MINC 2.0, which added support for 64-bit file sizes, internal compression, and a number of other modern features. Because of its extensible design, it has been easy to incorporate details of provenance in the header metadata, including an explicit processing history, unique identifiers, and vendor-specific scanner settings. This makes MINC ideal for use in large scale imaging studies and databases. It also makes it easy to adapt to new scanning sequences and modalities.

A randomized trial of intrapartum analgesia in women with severe preeclampsia.

OBJECTIVE: To estimate whether the cesarean delivery rate differs between women with severe preeclampsia who receive intrapartum epidural analgesia versus patient-controlled intravenous opioid analgesia. METHODS: Women with severe preeclampsia at at least 24 weeks' gestation were randomly assigned to receive either intrapartum epidural (n = 56) versus patient-controlled intravenous opioid analgesia (n = 60), and each was administered by a standardized protocol. The sample size was selected to have 80% power to detect at least a 50% difference in the predicted intergroup cesarean delivery rates. Data were analyzed by intent to treat. RESULTS: Selected maternal characteristics and neonatal outcomes were similar in the two groups. The cesarean delivery rates in the epidural group (18%) and the patient-controlled analgesia group (12%) were similar (P =.35). Women who received epidural analgesia were more likely to require ephedrine for the treatment of hypotension (9% versus 0%, P =.02), but their infants were less likely to require naloxone at delivery (9% versus 54%, P <.001). Epidural analgesia provided significantly better pain relief as determined by a visual analogue intrapartum pain score (P <.001) and a postpartum pain management survey (P =.002). CONCLUSION: Compared with patient-controlled intravenous opioid analgesia, intrapartum epidural analgesia did not significantly increase the cesarean delivery rate in women with severe preeclampsia at our level III center, and it provided superior pain relief.

A bistable computational model of recurring epileptiform activity as observed in rodent slice preparations.

We describe a computational model of epileptiform activity mimicking the activity exhibited by an animal model of epilepsy in vitro. The computational model permits generation of synthetic data to assist in the evaluation of new algorithms for epilepsy treatment via adaptive neurostimulation. The model implements both single-compartment pyramidal neurons and fast-spiking interneurons, arranged in a one-dimensional network using both excitatory and inhibitory synapses. The model tracks changes in extracellular ion concentrations, which determine the reversal potentials of membrane currents. Changes in simulated ion concentration provide positive feedback which drives the system towards the epileptiform state. One mechanism of positive feedback explored by this model is the conversion of pyramidal cells from regular spiking to intrinsic bursting as extracellular potassium concentration increases. One of the main contributions of this work is the development of a slow depression mechanism that enforces seizure termination. The network spontaneously leaves the seizure-like state as the slow depression variable decreases. This is one of the first detailed computational models of epileptiform activity, which exhibits realistic transitions between inter-seizure and seizure states, and back, with state durations similar to the in vitro model. We validate the computational model by comparing its state durations to those of the biological model. We also show that electrical stimulation of the computational model achieves seizure suppression comparable to that observed in the in vitro model.

Anagram software for cognitive research that enables specification of psycholinguistic variables.

Anagram tasks are frequently used in cognitive research, and the generation of new scrambled letter combinations is a task well suited to a software solution. Most available programs, however, do not allow experimenters to generate new anagrams flexibly or to characterize existing anagrams using psycholinguistic criteria. They also do not provide detailed information on their source dictionaries. We present anagram software that interfaces with CELEX2, an internationallyrecognized psycholinguistic database. This software allows users to capitalize on lexical variables and thus enables direct control of psycholinguistic features that may influence the cognitive processes involved in anagram solution.

Posttetanic count revisited: are measurements more reliable using the TOF-Watch accelerographic peripheral nerve stimulator?

OBJECTIVE: Measurement of profound neuromuscular block using posttetanic count is among the most subjective measurements made in clinical anesthesia. The TOF-Watch accelerographic peripheral nerve stimulator provides objective measurements of neuromuscular block that may improve our ability to quantitate intense blockade. METHODS: The TOF-Watch and Digi Stim III peripheral nerve stimulators were used to monitor onset and early recovery of neuromuscular response induced by rocuronium 0.6 mg/kg i.v. in 30 patients anesthetized with general anesthesia. After induction, train-of-four count (when present) was measured at one-min intervals. Subsequently, posttetanic count was measured at three-min intervals until the first response to train-of-four stimulation reappeared. RESULTS: Posttetanic count and train-of-four count measurements were determined to be consistently unreliable throughout the study in seven (23%) patients with the TOF-Watch stimulator and three (10%) patients with the Digi Stim III stimulator (p = NS). Among stimulators yielding reliable measurements, decreases in train-of-four count to 0/4 were noted earlier with the Digi Stim III monitor (median = 2 min) as compared with the TOF-Watch device (median = 4 min) (p < 0.05). Also, posttetanic count decreased to zero in only 35% of patients with the TOF-Watch stimulator versus 67% of patients with the Digi Stim III stimulator (p < 0.05). CONCLUSIONS: Both monitors were similar in their ability to predict return to TOFC = 1 as a function of PTC measurements. The TOF-Watch monitor is easy to apply even in inexperienced hands. However, the device yielded erroneous data in 23% of patients.