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The goal of the present study was to investigate whether hippocampal contribution to episodic memory retrieval varies as a function of age (8–9 versus 10–11 versus adults), performance levels (high versus low) and hippocampal sub-region (head, body, tail). We examined fMRI data collected during episodic retrieval from a large sample (N = 126). Participants judged whether a stimulus had been encoded previously, and, if so, which of three scenes it had been paired with (i.e., source judgment). For 8- to 9-years-olds as well as low-performing 10- to 11-year-olds, hippocampal activations did not reliably differentiate between trials on which item-scene associations were correctly recalled (correct source), incorrectly recalled (incorrect source), or trials on which the item was forgotten (miss trials). For high-performing 10–11-year olds and low-performing adults, selective hippocampal activation was observed for correct source relative to incorrect source and miss trials; this effect was observed across the entire hippocampus. For high-performing adults, hippocampal activation also distinguished between correct and incorrect source trialsl, but only in the hippocampal head, suggesting that good performance in adults is associated with more focal hippocampal recruitment. Thus, both age and performance are important factors for understanding the development of memory and hippocampal function.

We have reported previously that intensive preparation for a standardized test that taxes reasoning leads to changes in structural and functional connectivity within the frontoparietal network. Here, we investigated whether reasoning instruction transfers to improvement on unpracticed tests of reasoning, and whether these improvements are associated with changes in neural recruitment during reasoning task performance. We found behavioral evidence for transfer to a transitive inference task, but no evidence for transfer to a rule generation task. Across both tasks, we observed reduced lateral prefrontal activation in the trained group relative to the control group, consistent with other studies of practice-related changes in brain activation. In the transitive inference task, we observed enhanced suppression of task-negative, or default-mode, regions, consistent with work suggesting that better cognitive skills are associated with more efficient switching between networks. In the rule generation task, we found a pattern consistent with a training-related shift in the balance between phonological and visuospatial processing. Broadly, we discuss general methodological considerations related to the analysis and interpretation of training-related changes in brain activation. In summary, we present preliminary evidence for changes in brain activation associated with practice of high-level cognitive skills.

Purpose: To compare recovery experienced during inpatient rehabilitation among individuals with traumatic brain injury (TBI) based on whether their acute care included the Clinical Institute Withdrawal Assessment for Alcohol (CIWA) protocol., Design: Participants included 234 individuals with TBI who completed inpatient rehabilitation at a TBI Model Systems site. Of these, 67 patients were treated using the CIWA protocol (TBI + CIWA); 167 patients were treated for TBI alone (TBI only). Demographic, injury, and treatment variables between the 2 groups were compared. A repeated-measures analysis of variance (ANOVA) compared Disability Rating Scale (DRS) scores between the groups at admission and discharge from inpatient rehabilitation., Results: The 2 groups did not significantly differ on DRS scores at admission to inpatient rehabilitation: TBI + CIWA, M = 9.6 (SD = 3.5) vs. TBI only, M = 10.1 (SD = 4.2). There was a significant difference in DRS scores at discharge, with the TBI + CIWA group having lower scores: TBI + CIWA, M = 6.4 ( SD = 1.9) vs. TBI only, M = 7.0 (SD = 2.2). A repeated-measures ANOVA of DRS scores from admission to discharge revealed a significant between-subjects effect based on patients' Mississippi categorization of posttraumatic amnesia (PTA) duration ( p < .001) and age ( p = .016) but not based on their CIWA status ( p = .068). A post hoc comparison including age as a covariate revealed a significant difference based on CIWA status ( p = .013) within the "moderate" injury group at discharge, with the TBI + CIWA group having lower discharge DRS scores., Conclusions: Given the significant symptom overlap between alcohol withdrawal and PTA, it is likely that these 2 delirium presentations are confounded during the initial recovery from TBI, leading to "overestimation" of injury severity-particularly among individuals with moderate TBI. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Survivability characteristics after cardiopulmonary resuscitation in the population with spinal cord injury (SCI) are unclear but may be useful for advanced care planning discussions with patients. Retrospective evaluation from records of all SCI patients over 10 yr at a Department of Veterans Affairs medical center who experienced in-hospital cardiac arrest was performed. Demographic data and other common measurements were recorded. Thirty-six male subjects were identified, and only two patients survived to discharge (5.5% survival rate), both of whom were admitted for nonacute issues and were asymptomatic shortly before the cardiac arrest. The mean age at the time of cardiopulmonary arrest was 62.4 yr, with a mean time from cardiac arrest to death of 3.02 d. No significant demographic parameters were identified. Overall, SCI likely portends worse outcome for acutely ill patients in the situation of a cardiac arrest. Conclusions are limited by sample size.

Across the medical literature, delayed diagnosis and treatment leads to more costly and worse outcomes. Rehabilitation patients, especially those with polytrauma, often have a complex mixture of medical, social, and psychological health problems that can impair effective diagnosis and treatment. The case presentation describes the procession toward the diagnosis of ulcerative colitis in a preinjury asymptomatic male, suggesting a potential mechanism for its emergence and describing the effect of delayed diagnosis on the efficiency of rehabilitative care. As such, the differential diagnosis for early posttraumatic diarrhea should remain broad, particularly if unexplained or ineffectively controlled.

The past decade has seen an explosive increase in the number of peer reviewed papers reporting new scientific findings in geomorphology (including fans, channels, floodplains and landscape evolution), geologic mapping, tectonics and faulting, coastal processes, lava flows, hydrology (especially snow and runoff routing), glaciers and geo-archaeology. A common genesis of such findings is often newly available decimeter resolution 'bare Earth' geodetic images, derived from airborne laser swath mapping, a.k.a. airborne LiDAR, observations. In this paper we trace nearly a half century of advances in geodetic science made possible by space age technology, such as the invention of short-pulse-length high-pulse-rate lasers, solid state inertial measurement units, chip-based high speed electronics and the GPS satellite navigation system, that today make it possible to map hundreds of square kilometers of terrain in hours, even in areas covered with dense vegetation or shallow water. To illustrate the impact of the LiDAR observations we present examples of geodetic images that are not only stunning to the eye, but help researchers to develop quantitative models explaining how terrain evolved to its present form, and how it will likely change with time. Airborne LiDAR technology continues to develop quickly, promising ever more scientific discoveries in the years ahead.

Myelogenous leukaemia was found in a Russell's viper, a Honduran milk snake, a marine toad, a Byrne's marsupial mouse and an African hedgehog. Lymphocytic leukaemia was present in a broad banded copperhead and an Indian lion. Visceral lymphomatosis was observed in a snowy owl.

An important bound on the accuracy of modern techniques for monitoring polar motion is established by intercomparison of measurement series from two different observing techniques, very long baseline interferometry and satellite laser ranging. The root-mean-square differences between the estimates of the pole position from both techniques are shown to be only 2 milliseconds of arc (about 6 centimeters at one Earth radius). In the absence of common systematic errors, these differences bound the total errors in both sets of estimates. An initial investigation did not reveal any clear signature in the pole position that seems to be associated with major earthquakes. Continued measurements at this level of accuracy hold promise for resolving long-standing arguments over such questions as the nature of the excitation mechanism required to maintain the motion of the pole.

The estimated median accuracy of 194 single-day determinations of the earth's angular position in space is 0.7 millisecond (0.01 arc second). Comparison with classical astronomical results gives agreement to about the expected 2-millisecond uncertainty of the 5-day averages obtained by the Bureau International de l'Heure. Little evidence for very rapid variations in the earth's rotation is present in the data.

Sixty-eight heroin addicts maintained for 40 weeks on a regimen of methadyl acetate or methadone hydrochloride in a double-blind study were transferred to a uniform dose of 60 mg of methadone daily at the end of their tenure in the study. They were observed for the ensuing six weeks, during which their daily methadone doses were adjusted according to their clinical needs. Patients were observed for symptoms and signs of discomfort and for the amount of illicit drug use during this period of transition. The results indicate that patients maintained on a regimen of methadyl acetate can be readily restabilized with methadone and that sudden decrease of the methadone dose tends to result in the patient's supplementing with illicit heroin. Conversely, increasing methadone doses resulted in a corresponding reduction in illicit drug use. It is suggested that a chronic covert abstinence syndrome may exist in some patients receiving long-term methadone maintenance therapy, and that while it may contribute to their continued illicit drug use, it may have a different pathophysiologic basis and require different therapeutic considerations.

Variations in the earth's rotation (UT1) and length of day have been tracked at the submillisecond level by astronomical radio interferometry and laser ranging to the LAGEOS satellite. Three years of regular measurements reveal complex patterns of variations including UT1 fluctuations as large as 5 milliseconds in a few weeks. Comparison of the observed changes in length of day with variations in the global atmospheric angular momentum indicates that the dominant cause of changes in the earth's spin rate, on time scales from a week to several years, is the exchange of angular momentum between the atmosphere and the mantle. The unusually intense El Niño of 1982-1983 was marked by a strong peak in the length of day.