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Accurate assessments of sea turtle populations are essential for determining population trends and formulating conservation plans for the recovery of these imperiled species. Although counting nesting females and nests has been widely used to assess abundance, surveys of in-water populations can provide a more effective means of measuring the success of recovery actions. An in-water survey within the Pamlico-Albemarle Estuarine Complex of North Carolina, USA, was begun in 1995 to monitor trends in sea turtle populations, and 3 sampling periods were established: 1995-1997, 2001-2003, and 2007-2009. A significant increase in loggerhead Caretta caretta captures was detected among the 3 sampling periods, while the addition of sampling in 2007-2009 (n = 887 unique individuals) revealed significant increases in capture rates of green Chelonia mydas and Kemp’s ridley Lepidochelys kempii sea turtles. Species composition also changed from a dominance of loggerheads in the early sampling periods to an equivalent proportion of green and loggerhead sea turtles in 2007-2009; North Carolina stranding data displayed similar changes in species composition during 2007-2009. Though logistically difficult, long-term in-water studies are critical for monitoring trends in sea turtle populations and implementing effective conservation plans.

Monitoring animal populations is essential to conservation, and complex monitoring goals require complex resources. Variable detection probabilities can create uncertainty in trends and abundances estimated from point count surveys (e.g. nest counts), as well as from more expensive monitoring methods such as line transect surveys (e.g. aerial surveys). Point count surveys in the form of nest counts are the most common form of sea turtle population monitoring, although in-water aerial surveys are also conducted. We used a loggerhead sea turtle Caretta caretta population model to generate stochastic ‘known’ populations from which we mimicked the information we would obtain from nest counts and from in-water aerial surveys. We subjected the populations to environmental or anthropogenic impacts and compared trends in each monitoring metric with the trend in simulated turtle population size in terms of adult equivalents. Over long time frames, either monitoring scheme performed equally well (mean population growth rates λ over 50 yr were within 1% of the growth rate estimated from simulated adult equivalents). Over shorter time frames, total adult females estimated from simulated nest counts generally tracked closer to adult equivalents than did abundance estimated from simulated aerial surveys; and λ for the nest count metric generally had a lower median absolute relative error. Aerial surveys added value if population impacts affected young turtles (which can take 20-30 yr to become nesters) or if impacts changed the population structure (e.g. changed the stable age distribution). For effective monitoring over short time frames, both monitoring schemes might be warranted.

Multiple populations of green sea turtles Chelonia mydas show signs of population recovery. In Hawaii (USA), green turtles have increased 5.4% yr-1 since 1973, but fluctuations in census counts of nesting females make recovery diagnosis difficult. Evaluating demographic rates for temporal change and in relation to population density, and indicators of recruitment to sea turtle nesting populations, will ultimately improve population assessments. Using linear mixed and multistate open robust design models, we estimated the demographic indicators (DIs) of size at maturity, nester carapace length, breeding probability, and adult female survival using 3677 tagged nesting green turtles from 1973 to 2010 in Hawaii. To evaluate changes with density, we correlated the DIs with nesting female counts. We estimated size at maturity, assuming that newly tagged nesters are new recruits and that first-time nesters have statistically significant smaller carapace length than recaptures, but the difference in size was only ~0.5 cm. Mean nester carapace length (range: 89.21-91.69 cm) and breeding probability (range: 0.0766-0.444 yr-1) showed directional changes over time, suggesting shifts in age structure that could be due to recruitment. The top-ranked model predicted constant female survival over time (S = 0.929 yr-1, 95% CI: 0.924-0.933, model likelihood = 1.00). Counter to our hypothesis based on density-dependence, breeding probability increases with increasing nester abundance. This work contributes to a growing set of studies evaluating sea turtle demography for temporal variability and is the first for Hawaiian green turtles. Our study demonstrates that some easily monitored demographic variables may serve as indicators of population change.

Understanding the drivers of fisheries bycatch is essential for limiting its impacts on vulnerable species. Here we present a model to estimate the relative magnitude of sea turtle bycatch in major coastal fisheries across the southeastern US based on spatiotemporal variation in fishing effort and the simulated distributions of juvenile Kemp's ridley ( Lepidochelys kempii ) and green ( Chelonia mydas ) sea turtles recruiting from oceanic to nearshore habitats. Over the period modeled (1996-2017), bycatch in recreational fisheries was estimated to be greater than the sum of bycatch that occurred in commercial fisheries that have historically been considered high risks to turtles (e.g., those using trawls, gillnets, and bottom longlines). Prioritizing engagement with recreational anglers to reduce bycatch could be especially beneficial to sea turtle populations. Applying lessons learned from efforts to protect turtles in commercial fisheries may help meet the challenges that arise from the large, diffuse recreational fishing sector., Competing Interests: We declare we have no competing interests., (© 2023 The Author(s).)

Vinyl chloride (VC) is a common groundwater pollutant generated during anaerobic biodegradation of chlorinated solvents (e.g., trichloroethene (TCE) or tetrachloroethene (PCE)). Aerobic VC biodegradation by etheneotrophs can support anaerobic PCE and TCE bioremediation to achieve complete removal in situ. However, anaerobic bioremediation strategies necessitate biostimulation with electron donors that are fermented in situ, generating organic acids that could influence aerobic VC biodegradation processes. We examined the effect of organic acids (lactate, acetate, propionate, and butyrate) on aerobic VC biodegradation by VC-assimilating etheneotrophs Mycobacterium strain JS60 and Nocardioides strain JS614. Strain JS60 grew on all organic acids tested, while strain JS614 did not respond to lactate. VC-grown strain JS60 fed VC and one or more organic acids showed carbon catabolite repression (CCR) behavior where VC biodegradation occurred only after organic acids were depleted. In contrast, CCR was not evident in VC-grown strain JS614, which degraded VC and organic acids simultaneously. Acetate-grown JS60 showed similar CCR behavior when fed VC and a single organic acid, except that extended lag periods (5-12 days) occurred before VC oxidation ensued. Acetate-grown JS614 fed VC and either acetate or butyrate displayed 5-8 day lag periods before simultaneous VC and organic acid biodegradation. In contrast, acetate-grown JS614 degraded VC and propionate without a significant lag, suggesting a regulatory link between propionate and VC oxidation in JS614. Different global regulatory mechanisms controlling VC biodegradation in the presence of organic acids in etheneotrophs have implications for developing combined anaerobic-aerobic bioremediation strategies at chlorinated ethene-contaminated sites. KEY POINTS: • With organic acids present, VC utilization was repressed in JS60, but not in JS614 • Strain JS60 grew readily on lactate, while strain JS614 did not • Propionate alleviated lag periods for VC utilization in acetate-grown JS614., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Chlorinated ethene (CE) groundwater contamination is commonly treated through anaerobic biodegradation (i.e., reductive dechlorination) either as part of an engineered system or through natural attenuation. Aerobic biodegradation has also been recognized as a potentially significant pathway for the removal of the lower CEs cis-1,2-dichloroethene (cDCE) and vinyl chloride (VC). However, the role of aerobic biodegradation under low oxygen conditions typical of contaminated groundwater is unclear. Bacteria capable of aerobic VC biodegradation appear to be common in the environment, while aerobic biodegradation of cDCE is less common and little is known regarding the organisms responsible. In this study, we investigate the role of aerobic cDCE and VC biodegradation in a mixed contaminant plume (including CEs, BTEX, and ketones) at Naval Air Station North Island, Installation Restoration Site 9. Sediment and groundwater collected from the plume source area, mid-plume, and shoreline were used to prepare microcosms under fully aerobic (8 mg/L dissolved oxygen (DO)) and suboxic (< 1 mg/L DO) conditions. In the shoreline microcosms, VC and cDCE were rapidly degraded under suboxic conditions (100% and 77% removal in < 62 days). In the suboxic VC microcosms, biodegradation was associated with a > 5 order of magnitude increase in the abundance of functional gene etnE, part of the aerobic VC utilization pathway. VC and cDCE were degraded more slowly under fully aerobic conditions (74% and 30% removal) in 110 days. High-throughput 16S rRNA and etnE sequencing suggest the presence of novel VC- and cDCE-degrading bacteria. These results suggest that natural aerobic biodegradation of cDCE and VC is occurring at the site and provide new evidence that low (< 1 mg/L) DO levels play a significant role in natural attenuation of cDCE and VC., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Fluorescence in situ hybridization (FISH) can provide information on the morphology, spatial arrangement, and local environment of individual cells enabling the investigation of intact microbial communities. GeneFISH uses polynucleotide probes and enzymatic signal amplification to detect genes that are present in low copy numbers. Previously, this technique has only been applied in a small number of closely related organisms. However, many important functional genes, such as those involved in xenobiotic degradation or pathogenesis, are present in diverse microbial strains. Here, we present a geneFISH method for the detection of the functional gene etnC, which encodes the alpha subunit of an alkene monooxygenase used by aerobic ethene and vinyl chloride oxidizing bacteria (etheneotrophs). The probe concentration was optimized and found to be 100 pg/μl, similar to previous geneFISH reports. Permeabilization was necessary for successful geneFISH labeling of Mycobacteria; sequential treatment with lysozyme and achromopeptidase was the most effective treatment. This method was able to detect etnC in several organisms including Mycobacteria and Nocardioides, demonstrating for the first time that a single geneFISH probe can detect a variety of alleles (>80% sequence similarity) across multiple species. Detection of etnC with geneFISH has practical applications for bioremediation. This method can be readily adapted for other functional genes and has broad applications for investigating microbial communities in natural and engineered systems., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Population monitoring must be accurate and reliable to correctly classify population status. For sea turtles, nesting beach surveys are often the only population-level surveys that are accessible. However, process and observation errors, compounded by delayed maturity, obscure the relationship between trends on the nesting beach and the population. We present a simulation-based tool, monitoring strategy evaluation (MoSE), to test the relationships between monitoring data and assessment accuracy, using green sea turtles, Chelonia mydas, as a case study. To explore this first application of MoSE, we apply different treatments of population impacts to virtual true populations, and sample the nests or nesters, with observation error, to test if the observation data can be used to diagnose population status accurately. Based on the observed data, we examine population trend and compare it to the known values from the operating model. We ran a series of scenarios including harvest impacts, cyclical breeding probability, and sampling biases, to see how these factors impact accuracy in estimating population trend. We explored the necessary duration of monitoring for accurate trend estimation and the probability of a false trend diagnosis. Our results suggest that disturbance type and severity can have important and persistent effects on the accuracy of population assessments drawn from monitoring nesting beaches. The underlying population phase, age classes disturbed, and impact severity influenced the accuracy of estimating population trend. At least 10 yr of monitoring data is necessary to estimate population trend accurately, and >20 yr if juvenile age classes were disturbed and the population is recovering. In general, there is a greater probability of making a false positive trend diagnosis than a false negative, but this depends on impact type and severity, population phase, and sampling duration. Improving detection rates to 90% does little to lower probability of a false trend diagnosis with shorter monitoring spans. Altogether, monitoring strategies for specific populations may be tailored based on the impact history, population phase, and environmental drivers. The MoSE is an important framework for analysis through simulation that can comprehensively test population assessments for accuracy and inform policy recommendations regarding the best monitoring strategies., (Published 2019. This article has been contributed by U.S. Government employees and their work is in the public domain in the USA.)

Conservation planning for protected species often relies on estimates of life-history parameters. A commonly used parameter is the instantaneous maximum population growth rate ( r max ) that can be used to limit removals and design recovery targets. Estimation of r max can be challenging because of limited availability of species- and population-specific data and life-history information. We applied a method proposed by Neil and Lebreton, originally developed for birds, to loggerhead turtles. The method uses age-at-first-reproduction and adult survival to estimate r max . We used a variety of datasets and matrix population models to confirm an allometric assumption required by the method, and to generate estimates of age-at-first-reproduction and adult survival. A meta-analysis was applied to parameters from reported growth curves, which were then combined with the size distribution of neophyte nesters to derive estimates of age-at-first-reproduction. Adult survival rates were obtained from an existing matrix population model. Monte Carlo simulation was then used to combine the estimates of the allometric coefficients, age-at-first-reproduction, and adult survival to obtain a probability distribution of approximate r max values. Estimated annual maximum population growth rates averaged 0.024, with a mode of 0.017 and a 95% highest density interval of 0.006-0.047. These estimates were similar to values reported by others using different methods and captured the variability in positive, annual change estimates across nesting beach sites for the northwest Atlantic loggerhead population. The use of life-history parameters has a long history in wildlife and fisheries management and conservation planning. Our estimates of r max , while having some biases and uncertainty, encompassed values presently used in recovery planning for loggerhead turtles and offer additional information for the management of endangered and threatened species., Competing Interests: None declared.

Vinyl chloride (VC) is a common groundwater contaminant and known human carcinogen. Three major bacterial guilds are known to participate in VC biodegradation: aerobic etheneotrophs and methanotrophs, and anaerobic organohalide-respiring VC-dechlorinators. We investigated the spatial relationships between functional genes representing these three groups of bacteria (as determined by qPCR) with chlorinated ethene concentrations in a surficial aquifer at a contaminated site. We used cryogenic soil coring to collect high-resolution aquifer sediment samples and to preserve sample geochemistry and nucleic acids under field conditions. All samples appeared to be anaerobic (i.e., contained little to no dissolved oxygen). VC biodegradation associated functional genes from etheneotrophs (etnC and/or etnE), methanotrophs (mmoX and/or pmoA), and anaerobic VC-dechlorinators (bvcA and/or vcrA) coexisted in 48% of the samples. Transcripts of etnC/etnE and bvcA/vcrA were quantified in contemporaneous groundwater samples, indicating co-located gene expression. Functional genes from etheneotrophs and anaerobic VC-dechlorinators were correlated to VC concentrations in the lower surficial aquifer (p < 0.05). Methanotroph functional genes were not correlated to VC concentrations. Cryogenic soil coring proved to be a powerful tool for capturing high-spatial resolution trends in geochemical and nucleic acid data in aquifer sediments. We conclude that both aerobic etheneotrophs and anaerobic VC-dechlorinators may play a significant role in VC biodegradation in aquifers that have little dissolved oxygen., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Variation in the shell coiling, or chirality, of land snails provides an opportunity to investigate the potential for "single-gene" speciation, because mating between individuals of opposite chirality is believed not possible if the snails mate in a face-to-face position. However, the evidence in support of single-gene speciation is sparse, mostly based upon single-gene mitochondrial studies and patterns of chiral variation between species. Previously, we used a theoretical model to show that as the chiral phenotype of offspring is determined by the maternal genotype, occasional chiral reversals may take place and enable gene flow between mirror image morphs, preventing speciation. Here, we show empirically that there is recent or ongoing gene flow between the different chiral types of Japanese Euhadra species. We also report evidence of mating between mirror-image morphs, directly showing the potential for gene flow. Thus, theoretical models are suggestive of gene flow between oppositely coiled snails, and our empirical study shows that they can mate and that there is gene flow in Euhadra . More than a single gene is required before chiral variation in shell coiling can be considered to have created a new species.

(E)-2-alkenals are aldehydes containing an unsaturated bond between the alpha and beta carbons. 2-alkenals are produced by many organisms for defense against predators and secretions containing (E)-2-alkenals cause predators to stop attacking and allow the prey to escape. Chemical ecologists have described many alkenal compounds with 3-20 carbons common, having varied positions of double bonds and substitutions. How do these defensive alkenals act to deter predators? We have tested the effects of (E)-2-alkenals with 6-12 carbons on transient receptor potential channels (TRP) commonly found in sensory neurons. We find that (E)-2-alkenals activate transient receptor potential ankyrin subtype 1 (TRPA1) at low concentrations-EC50s 10-100 µM (in 0 added Ca(2+) external solutions). Other TRP channels were either weakly activated (TRPV1, TRPV3) or insensitive (TRPV2, TRPV4, TRPM8). (E)-2-alkenals may activate TRPA1 by modifying cysteine side chains. However, target cysteines include others beyond the 3 in the amino-terminus implicated in activation, as a channel with cysteines at 621, 641, 665 mutated to serine responded robustly. Related chemicals, including the aldehydes hexanal and decanal, and (E)-2-hexen-1-ol also activated TRPA1, but with weaker potency. Rat trigeminal nerve recordings and behavioral experiments showed (E)-2-hexenal was aversive. Our results suggest that TRPA1 is likely a major target of these commonly used defensive chemicals., (© The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

We investigated the extent that the 2010 Deepwater Horizon oil spill potentially affected oceanic-stage sea turtles from populations across the Atlantic. Within an ocean-circulation model, particles were backtracked from the Gulf of Mexico spill site to determine the probability of young turtles arriving in this area from major nesting beaches. The abundance of turtles in the vicinity of the oil spill was derived by forward-tracking particles from focal beaches and integrating population size, oceanic-stage duration and stage-specific survival rates. Simulations indicated that 321 401 (66 199-397 864) green (Chelonia mydas), loggerhead (Caretta caretta) and Kemp's ridley (Lepidochelys kempii) turtles were likely within the spill site. These predictions compared favourably with estimates from in-water observations recently made available to the public (though our initial predictions for Kemp's ridley were substantially lower than in-water estimates, better agreement was obtained with modifications to mimic behaviour of young Kemp's ridley turtles in the northern Gulf). Simulations predicted 75.2% (71.9-76.3%) of turtles came from Mexico, 14.8% (11-18%) from Costa Rica, 5.9% (4.8-7.9%) from countries in northern South America, 3.4% (2.4-3.5%) from the United States and 1.6% (0.6-2.0%) from West African countries. Thus, the spill's impacts may extend far beyond the current focus on the northern Gulf of Mexico., (© 2015 The Authors.)

Mental health professionals who provide medicolegal services need to be aware of the very important differences between clinical and retained expert/forensic roles. This column offers a distinction between clinical and forensic roles in terms of responsibilities, objectives, and guiding ethical principles. Existing professional guidelines and other views from the medical literature that discourage the mixing of such roles are reviewed. The conflation of clinical and forensic roles and the attendant risks are considered, in terms of both competing interests and the possible ethical threat associated with assuming a dual role. Knowingly or unwittingly assuming a dual role is potentially harmful to the therapeutic alliance, threatens the expert's objectivity, and may jeopardize a patient's legal case. Guidance is offered as to how to avoid conflating clinical and forensic roles when compelled to provide medicolegal services.

The Gulf of Mexico is one of the most ecologically and economically valuable marine ecosystems in the world and is affected by a variety of natural and anthropogenic phenomena including climate, hurricanes, coastal development, agricultural runoff, oil spills, and fishing. These complex and interacting stressors, together with the highly dynamic nature of this ecosystem, present challenges for the effective management of its resources. We analyze a compilation of over 100 indicators representing physical, biological, and economic aspects of the Gulf of Mexico and find that an ecosystem-wide reorganization occurred in the mid-1990s. Further analysis of fishery landings composition data indicates a major shift in the late 1970s coincident with the advent of US national fisheries management policy, as well as significant shifts in the mid-1960s and the mid-1990s. These latter shifts are aligned temporally with changes in a major climate mode in the Atlantic Ocean: the Atlantic Multidecadal Oscillation (AMO). We provide an explanation for how the AMO may drive physical changes in the Gulf of Mexico, thus altering higher-level ecosystem dynamics. The hypotheses presented here should provide focus for further targeted studies, particularly in regard to whether and how management should adjust to different climate regimes or states of nature. Our study highlights the challenges in understanding the effects of climatic drivers against a background of multiple anthropogenic pressures, particularly in a system where these forces interact in complex and nonlinear ways., (© 2015 John Wiley & Sons Ltd.)

Studies on the classic shell colour and banding polymorphism of the land snail Cepaea played a crucial role in establishing the importance of natural selection in maintaining morphological variation. Cepaea is also a pre-eminent model for ecological genetics because the outward colour and banding phenotype is entirely genetically determined, primarily by a 'supergene' of at least five loci. Unfortunately, progress in understanding the evolution and maintenance of the Cepaea polymorphism stalled, partly because of a lack of genetic markers. With a view to re-establish Cepaea as a prominent model of molecular ecology, we made six laboratory crosses of Cepaea nemoralis, five of which segregated for shell ground colour (C) and the presence or absence of bands (B). First, scoring of colour and banding in 323 individuals found no recombination between the C and B loci of the supergene. Second, using restriction site-associated DNA sequencing (RAD-Seq) of two parents and 22 offspring, we identified 44 anonymous markers putatively linked to the colour (C) and banding (B) loci. The genotype of eleven of the most promising RAD-Seq markers was independently validated in the same 22 offspring, then up to a further 146 offspring were genotyped. The closest RAD-Seq markers scored are within ~0.6 centimorgan (cM) of the C-B supergene linkage group, with the combined loci together forming a 35.8 cM linkage map of markers that flank both sides of the Cepaea C-B supergene., (© 2013 John Wiley & Sons Ltd.)

New islands present the perfect opportunity for a species to get a fresh start and undergo adaptive radiation. For Galápagos land snails, both competition and resource diversity have together led to opportunity knocking twice., (Copyright 2010 Elsevier Ltd. All rights reserved.)

A model of species interactions based on their use of shared resources was proposed in 1972 by Robert MacArthur and later expanded in an article (1980) and a book (1982) by David Tilman. This "resource-ratio theory" has been used to make a number of testable predictions about competition and community patterns. We reviewed 1,333 papers that cite Tilman's two publications to determine whether predictions of the resource-ratio theory have been adequately tested and to summarize their general conclusions. Most of the citations do not directly test the theory: only 26 studies provide well-designed tests of one or more predictions, resulting in 42 individual tests of predictions. Most of these tests were conducted in the laboratory or experimental microcosms and used primary producers in freshwater systems. Overall, the predictions of the resource-ratio theory were supported 75% of the time. One of the primary predictions of the model, that species dominance varies with the ratio of resource availabilities, was supported by 13 of 16 tests, but most other predictions have been insufficiently tested. We suggest that more experimental work in a variety of natural systems is seriously needed, especially studies designed to test predictions related to resource supply and consumption rates.

Background: Head injury is an important cause of morbidity and mortality in pediatrics. Comprehensive studies on outcome are scarce despite significant clinical concern that multiple areas of functioning may be impaired following moderate to severe head injury. The literature suggests that sequelae include not only medical problems but also impairments in cognitive functioning., Methods: A retrospective medical and psychology chart review of patients, age 1-18 years, admitted to the Children's Hospital of Eastern Ontario with moderate (Glasgow Coma Scale [GCS] 9-12) or severe head injury (GCS < or = 8) from November 1, 1993 until December 31, 1998 was conducted. Correlations were performed between medical variables (i.e., GCS, Pediatric Risk of Mortality [PRISM] III score, duration of ICU and hospital stay) and measures of intelligence and memory functioning., Results: Eighty-three children age 1 to 18 were included. Seventy percent of the children were classified as having a severe head injury. There was a mortality rate of thirteen percent. Younger age at injury, lower GCS, and higher PRISM III scores predicted higher mortality. Medical complications were documented systematically. Forty-four patients underwent at least one cognitive assessment and 17 of these children had intelligence testing at three points in time: baseline (< four months), early recovery (five to 15 months) and follow-up (16 to 38 months). The mean intelligence and memory scores fell within the average range at the latest point in follow-up. For those children who underwent three serial assessments, the mean verbal and performance IQ fell within the low average range at baseline improving significantly to fall within the average range by early recovery. Continued improvements were apparent in verbal memory beyond early recovery, with the mean obtained at follow-up falling within 1 SD of the normative mean. Despite the return to normal ranges for the group means the proportion of scores falling below 1.5 standard deviations from the mean was greater than population norms for verbal IQ, performance IQ and verbal memory. Lower GCS scores and longer duration of stay in ICU or hospital were predictive of lower nonverbal intelligence. Lower GCS was also predictive of lower visual memory scores., Conclusions: This study describes a population of Canadian children who suffered moderate or severe traumatic brain injury. Initial GCS was the best predictor of mortality and cognitive outcome. These children demonstrated a temporal improvement in intelligence and memory functioning, with their mean performance on these cognitive measures falling within the average range at 16 to 38 months postinjury, although there was considerable variability in the outcomes between individuals.

The differential representation of the toes/feet and fingers/hands along the medial and lateral surfaces of the cerebral cortices, respectively, may have diagnostic utility. Normative data for errors for toe and finger graphaesthesia and gnosis, as well as foot and finger agility, were collected for 86 children (ages 7 to 14). The fingers were more agile than the feet, and the right side of the body was more agile than the left side, regardless of age. A marked improvement in toe gnosis, but not in finger gnosis occurred in children after 11-12 years of age. A statistically significant interaction between laterality and gender was due to the greater numbers of errors for both toe and finger gnosis, displayed by girls for the left sides of their bodies compared to their right sides. This discrepancy was not significant for boys.

Late effects of radiotherapy on intellectual functioning have been well documented in children treated for posterior fossa tumors. Other aspects of cognitive functioning, such as memory, have not been adequately assessed in this population. This retrospective review reports on 15 children diagnosed with medulloblastoma or cerebellar astrocytoma who were administered a norm-referenced standardized test of memory functioning (i.e., Wide Range Assessment of Memory and Learning) an average of 3.5 years after treatment. Analyses revealed that sample means of IQ and memory were significantly lower than those of the normative population. No significant differences were found between the verbal and nonverbal IQ, or verbal and visual memory. Age at diagnosis accounted for a significant proportion of variability in the intelligence ratings but not in the memory indexes. The IQ scores of children less than 6 years of age at diagnosis were significantly lower than those of children diagnosed when over 6 years of age. Given the substantial variability within the older age group, there was insufficient power to detect true differences between memory index means for children by age at diagnosis. Follow-up assessments over 5 years may better identify the long-term effects of radiotherapy on memory functioning.

Materials and Methods: A retrospective review of the neuropsychological and medical variables of 26 children who underwent a cortical resection as part of the management of their medically refractory epilepsy was conducted. Neuropsychological variables included pre- and postoperative measures of intelligence (Wechsler Scales) and memory functioning (Wide Range Assessment of Memory and Learning). Medical variables included age at onset of seizures, age at surgery, site of resection, and degree of seizure control postoperatively., Results: Twenty patients had temporal resections (13 left-sided). Six had extratemporal resections. In this series, cortical resection as treatment of epilepsy in children did not result in a significant change in performance on measures of intelligence or memory functioning. No significant correlation was found between the medical variables and the neuropsychological outcome.

Injection of 30 mg/kg of pilocarpine 24 h after systemic injection of lithium (3 mEq/kg) results in overt limbic motor seizures within about 30 min. Results of several experiments indicated that whereas food deprivation or repeated nociceptive stimulation during the previous 24 h decreased seizure onset times (SOTs) by about 11 to 12 min, food restriction, continuous lighting, or, handling during the previous 7 to 14 days increased SOTs by comparable durations. Early handling before weaning but not injections of clomimpramine also decreased SOTs. A difference of 18 min in the means of SOTs was produced by injecting either 1.0 (increased SOT) or 1.5 mg/kg (decreased SOT) of dexamethasome during the previous 24 h. A strong (multiple r=.87) association between SOTs and the amount of damage within five specific thalamic-limbic nuclei was observed. These results, in conjunction with blood corticosterone levels taken before and after induction of the seizures, suggest the neurochemical mechanisms affecting the range in SOTs could involve the adrenocorticotropic hormone (ACTH)-corticosterone system and influence the amount of post-seizure-induced damage.

Analyses of the data from 212 boys and girls, aged 7-14 years, demonstrated a relatively abrupt and permanent decrease in the numbers of errors for dichotic (left ear) word listening and for toe gnosis after the ninth year. This pattern was not observed for right ear errors, finger gnosis, or indices of finger and foot agility. The results are compatible with the hypothesis that the final differentiation of the paracentral lobules and adjacent corpus callosum by the most distal portions of the Anterior Cerebral Artery occurs around 9 or 10 years of age. Implications for the development of the sense of self, enhanced apprehension, and "the sense of a presence" are discussed.

33 university students listened to a 5-min. ambiguous narrative about a young boy (The Billy Story) while another 33 students did not. At the end of the final examination for the course the students were promised a 2% bonus mark if they could reconstruct the details of the story. Whereas only one student who heard the story could not recall any details, 30% of the students (n = 9) who never heard the story generated a false one. The numbers of accurate details recalled by those who heard the story decreased linearly with the time (5 through 30 days). Five times the numbers of the women than men who heard the story attributed the young boy's anomalous experience to sexual abuse.

Accuracies of two-point discrimination (successive 2-min increments between 0 and 10 mm) for the middle fingers and the middle toes for 87 children from ages 7 through 15 years were measured to obtain normative data. The finer discriminative capacity for the fingers rather than the toes was evident. Whereas discriminative accuracy approached the asymptote with distances equal to or greater than 4 mm for the fingers, distances equal to or greater than 8 mm were required for the toes. For this ontogenetic range, the effects for toes vs fingers was much greater than the effect size for age.

The hypothesis was tested that compensatory susceptibility to electroencephalographic driving and entrainment by weak (1 microT) time-varying, externally applied complex magnetic fields would occur in normal subjects following successive stimulation by different patterns. 43% of the volunteers showed evidence of driving during the application of the complex magnetic fields and indications of resonance (entrainment) during the first 10 sec. following the cessation of the fields. The volunteers who exhibited driving and entrainment could be discriminated from those who did not by their more frequent reported experiences of fear and odd tastes during the stimulation. They were also more likely to have a preexposure history of a sense of presence and to experience intense meaningfulness when reading or writing prose or poetry.

The intensity of reported vestibular experiences by normal volunteers (n = 127, over a 4-year period) increased significantly in a step-like manner during partial sensory deprivation when the daily geomagnetic activity exceeded about 15 nT; the effect size was equivalent to a correlation of about 0.33. Post hoc analyses indicated that the geomagnetic activity during the 3-h period at the beginning of the previous sleep cycle was the single greatest contributor. The enhanced occurrences of experiences that are similar to those associated with complex partial epileptic seizures suggests that specific stimuli associated with geomagnetic activity above about 15 nT affects specific regions of the human brain; the vulnerability occurs during the subsequent 24 h. However, in non-epileptic individuals these experiences must be amplified neurocognitively by removing input from auditory and visual modalities.

A protocol was designed to identify quantitative indicators of the function of the medial surfaces of the cerebral hemispheres. Normative data were collected from 40 volunteers for foot agility, toe gnosis, and toe graphaesthesia. A total of 100 patients (most of whom had been referred for possible closed-head injuries) completed thorough neuropsychological and cognitive assessments. Deficits for toe graphaesthesia were most consistently correlated with general brain impairment and with scores for tasks whose normal performance requires the integrity of structures within the dorsal half of the medial cerebral hemispheres.

A total of 20 men and 20 women listened to a 5-min. ambiguous narrative (the "Billy" story). When the subjects were asked (unexpectedly) to reconstruct the details of the story as a written narrative 30 min. later, women employed about 50% more words and comparably more accurate detail than the men. Covariance for pre-experimental experiences suggested that the women's proficiency could be related to the greater representation of linguistic processes within the right (non-dominant) hemisphere. The hypothesis that the classic deficit of reconstructional accuracy for events during the middle of a story is related to right-hemispheric inhibition was also supported. Subjects who recalled the fewest details reported more vivid dreaming during the subsequent two days.

During a single 20-min. exposure to partial sensory deprivation, the average duration of alpha rhythms over the left temporal lobe (T3) increased significantly compared to that for the right homologous region (T4). The percentage changes (increase) over time in the duration of alpha rhythms over the left temporal lobe but not the right temporal lobe were significantly correlated (.64) with histories of automatic behaviors (cessation of awareness) while only the relative increases over time in the durations of alpha rhythms over the right temporal lobe were correlated with histories of vestibular-auditory experiences (.42). The results suggest construct validity for differential hemispheric sources of some specific clusters of complex partial epileptic-like experiences that have been inferred to reflect the continuum of temporal lobe lability.

A total of 40 normal men and women were exposed under double blind conditions for 20 min to either sham-conditions or to 1 microT (10 mG) electromagnetic fields (known to produce long-term potentiation within hippocampal slices) that were applied primarily over the right temporal lobe, over the left temporal lobe or over both temporal lobes homogeneously. The men and women who received the stimulation over the right hemisphere rated their experiences as significantly more pleasant than those who received the same stimulation over the left hemisphere [eta = 0.51]. Covariance for the variation in ambient geomagnetic activity, which was negatively correlated with pleasantness, increased the significance of the experimental treatment. The potential clinical utility of applying computer-generated local and penetrative but weak intensity complex magnetic fields over portions of the human brain is discussed.

Because the dorsomedial thalamus is a major input to the prefrontal cortices, the reconstruction of experience (episodic memory) that is maximally dependent upon this subcortical structure should be influenced by one of its major correlates, hedonistic tone. University men and women (ns = 20) were shown two brief video-tapes of muricide and copulation among male rats during a lecture concerning instinctual behaviors. Two weeks later the subjects were asked to recall (written narratives) all of the details of the videotapes when they were in either the same or a different context. Although both groups generated similar numbers of words and employed words with comparable activation scores, the group who reconstructed the experiences outside of the context used words with significantly lower (eta = 0.59) pleasantness scores relative to the group who remembered the videotapes within the same setting.

The hypothesis of vectorial hemisphericity predicts that left hemispheric intrusions of the right hemispheric equivalent of the sense of self should be associated with the experience of a "presence" of someone else. The neurophenomenological profile of a woman whose medical history satisfied these theoretical criteria (verified electrical anomalies that could encourage phasic discharges within the right temporal lobe and atrophy within the left temporoparietal region) is presented. In addition to interactions between electrical seizures and thinking, she reported a long history of sensed presences, ego-alien intrusions, and "sudden knowing of the subsequent sequences of seizures" before they occurred clinically. The existence of these neurocognitive processes demands a reevaluation of the psychiatric default explanations of "hysteria" and questions the belief that "awareness during seizures" or "premonition of subsequent somatosensory experience" contraindicates an epileptic process.

In two separate experiments a total of 71 volunteers were asked to generate spontaneous narratives that were scored automatically by the Whissell Dictionary of Affect. During the narratives, weak (1 microT; 10 mG) magnetic fields were applied briefly through the temporal planes. In Experiment I, subjects who were exposed to simple sine wave or pulsed fields generated more scorable words that indicated lower activation and evaluation than sham-field conditions. In Experiment II subjects exposed to a computer-generated wave form, designed to simulate neuronal burst firing, generated narratives dominated by more pleasantness and less activation than a reference group. The possibility that this approach could be utilized to study the affective dimension of language selection was indicated.

Limbic seizures (forepaw clonus) were induced in Lewis rats by subcutaneous injections of lithium (3 mEq/kg) followed 24 h later by a muscarinic agent. Either 7 days before, 7 days after, or on the day of seizures, rats were inoculated with a spinal cord preparation. Other groups received these preparations but served as treatment (no seizure) controls. In three separate experiments, rats in which seizures had been induced at the time of inoculation displayed significant increases in the severity of clinical symptoms 14-20 days later relative to controls while rats in which seizures had been induced 7 days after inoculation displayed less severe symptoms; the latter effect was partially simulated by multiple injections of 1 mg/kg dexamethasone. The immunofacilitation effect was much stronger than the immunosuppression and explained 25-30% of the variance in the clinical severity scores.

Intermittent bursts of weak magnetic fields whose patterns simulate normal amygdaloidal-hippocampal activity were generated by computer over the right or left temporal regions of men and women during partial sensory deprivation. As predicted, women but not men reported greater apprehension during right-hemispheric but not left-hemispheric stimulation. Intrusions of right-hemispheric processes have been hypothesized to affect self-esteem adversely. These results also support the role of the right parahippocampal region in the production of panic attacks.