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Adaptive Function (adaptive + function)
Selected AbstractsHemispheric Surgery in Children with Refractory Epilepsy: Seizure Outcome, Complications, and Adaptive FunctionEPILEPSIA, Issue 1 2007Sheikh Nigel Basheer Summary:,Purpose: To describe seizure control, complications, adaptive function and language skills following hemispheric surgery for epilepsy. Methods: Retrospective chart review of patients who underwent hemispheric surgery from July 1993 to June 2004 with a minimum follow-up of 12 months. Results: The study population comprised 24 children, median age at seizure onset six months and median age at surgery 41 months. Etiology included malformations of cortical development (7), infarction (7), Sturge-Weber Syndrome (6), and Rasmussen's encephalitis (4). The most frequent complication was intraoperative bleeding (17 transfused). Age <2 yr, weight <11 kg, and hemidecortication were risk factors for transfusion. Postoperative complications included aseptic meningitis (6), and hydrocephalus (3). At median follow-up of 7 yr, 79% of patients are seizure free. Children with malformations of cortical development and Rasmussen's encephalitis were more likely to have ongoing seizures. Overall adaptive function scores were low, but relative strengths in verbal abilities were observed. Shorter duration of epilepsy prior to surgery was related significantly to better adaptive functioning. Conclusions: Hemispheric surgery is an effective therapy for refractory epilepsy in children. The most common complication was bleeding. Duration of epilepsy prior to surgery is an important factor in determining adaptive outcome. [source] Development of learned flavor preferencesDEVELOPMENTAL PSYCHOBIOLOGY, Issue 5 2006Kevin P. Myers Abstract Rats, like humans, are born with only a few innate flavor preferences and aversions. Preferences retain great plasticity throughout the lifespan because they are sensitive to modification by experience. From an early age, rats can rapidly learn to prefer or avoid a flavor (conditioned stimulus, CS) that is associated with a positive or negative unconditioned stimulus (US). The US may be the mother's milk, social or thermotactile stimulation, or other food-related stimuli. Flavor-flavor learning occurs when the CS flavor is mixed with a naturally preferred (e.g., sweet) or avoided (e.g., bitter) US flavor. Flavor preferences and aversions are also produced by USs that have postoral positive (e.g., nutritious) or negative (e.g., toxic) actions. These types of learning appear to involve different behavioral and neural mechanisms as indicated by differences in conditioned responses, effective temporal parameters, resistance to extinction, and neurochemical mechanisms. New evidence indicates that flavor-nutrient preference learning can occur before weaning and influence food selection after weaning. Flavor conditioning not only affects food choice, but can also significantly increase food acceptance, that is, total consumption. Thus, from an early age, learning processes shape the feeding behavior of animals. While primarily serving an adaptive function, learning may play a role in biasing individuals towards excessive intake and weight gain. © 2006 Wiley Periodicals, Inc. Dev Psychobiol 48: 380,388, 2006. [source] Hemispheric Surgery in Children with Refractory Epilepsy: Seizure Outcome, Complications, and Adaptive FunctionEPILEPSIA, Issue 1 2007Sheikh Nigel Basheer Summary:,Purpose: To describe seizure control, complications, adaptive function and language skills following hemispheric surgery for epilepsy. Methods: Retrospective chart review of patients who underwent hemispheric surgery from July 1993 to June 2004 with a minimum follow-up of 12 months. Results: The study population comprised 24 children, median age at seizure onset six months and median age at surgery 41 months. Etiology included malformations of cortical development (7), infarction (7), Sturge-Weber Syndrome (6), and Rasmussen's encephalitis (4). The most frequent complication was intraoperative bleeding (17 transfused). Age <2 yr, weight <11 kg, and hemidecortication were risk factors for transfusion. Postoperative complications included aseptic meningitis (6), and hydrocephalus (3). At median follow-up of 7 yr, 79% of patients are seizure free. Children with malformations of cortical development and Rasmussen's encephalitis were more likely to have ongoing seizures. Overall adaptive function scores were low, but relative strengths in verbal abilities were observed. Shorter duration of epilepsy prior to surgery was related significantly to better adaptive functioning. Conclusions: Hemispheric surgery is an effective therapy for refractory epilepsy in children. The most common complication was bleeding. Duration of epilepsy prior to surgery is an important factor in determining adaptive outcome. [source] CONCORDANCE OF THE CIRCADIAN CLOCK WITH THE ENVIRONMENT IS NECESSARY TO MAXIMIZE FITNESS IN NATURAL POPULATIONSEVOLUTION, Issue 4 2008Kevin J. Emerson The ubiquity of endogenous, circadian (daily) clocks among eukaryotes has long been held as evidence that they serve an adaptive function, usually cited as the ability to properly time biological events in concordance with the daily cycling of the environment. Herein we test directly whether fitness is a function of the matching of the period of an organism's circadian clock with that of its environment. We find that fitness, measured as the per capita expectation of future offspring, a composite measure of fitness incorporating both survivorship and reproduction, is maximized in environments that are integral multiples of the period of the organism's circadian clock. Hence, we show that organisms require temporal concordance between their internal circadian clocks and their external environment to maximize fitness and thus the long-held assumption is true that, having evolved in a 24-h world, circadian clocks are adaptive. [source] Comparison of Adaptive Behavior in Children With Heavy Prenatal Alcohol Exposure or Attention-Deficit/Hyperactivity DisorderALCOHOLISM, Issue 11 2009Nicole Crocker Background:, Adaptive behavior, the ability to respond successfully to everyday demands, may be especially sensitive to the effects of heavy prenatal alcohol exposure. Similar adaptive dysfunction is common in other developmental disorders including attention-deficit/hyperactivity disorder (ADHD). ADHD is frequently present in alcohol-exposed children and this overlap in clinical presentation makes identification of alcohol-exposed children difficult. Direct comparison of children with prenatal alcohol exposure and ADHD may yield distinct patterns of cognitive and behavioral performance and add to growing knowledge of the neuropsychological and behavioral profile of prenatal alcohol exposure. Therefore, the aim of the current study was to compare adaptive behavior in children with histories of heavy prenatal alcohol exposure (ALC), nonexposed children with ADHD (ADHD), and typically developing controls (CON). Methods:, Sixty-five children (ALC = 22, ADHD = 23, CON = 20) were selected from a larger ongoing study of the behavioral teratogenicity of alcohol. Alcohol-exposed and control participants were selected to match the ADHD subjects on age, sex, socioeconomic status, and race/ethnicity. Caregivers were administered the Vineland Adaptive Behavior Scales, a semi-structured interview, and were asked to rate their child's behavior on 3 domains of adaptive function. Data were analyzed using regression techniques. Results:, Relative to controls, children in both the ALC and ADHD groups showed adaptive behavior deficits on all 3 domains and children in the ALC group were significantly more impaired than the ADHD group on the daily living skills domain. Within the ALC group, socialization standard scores were lower at older ages. This negative relationship between age and standard scores in the ALC group was also observed on the communication domain, a finding not previously reported. Conclusions:, This study suggests that both children with prenatal alcohol exposure and children with ADHD show impairments in adaptive function relative to controls, but that the pattern of impairment differs between these clinical groups. Adaptive ability in children with prenatal alcohol exposure is characterized by an arrest in development, as evidenced by a lack of improvement with age in socialization and communication scores. In contrast, children with ADHD exhibit a developmental delay in adaptive ability as their scores continued to improve with age, albeit not to the level of control children. Continued research focused on elucidating the patterns of deficits that exist in alcohol-exposed children ultimately will lead to improved differential diagnosis and effective interventions. [source] Daily oscillations in liver function: diurnal vs circadian rhythmicityLIVER INTERNATIONAL, Issue 3 2004Alec J. Davidson Abstract: The rodent suprachiasmatic nucleus (SCN), a site in the brain that contains a light-entrained biological (circadian) clock, has been thought of as the master oscillator, regulating processes as diverse as cell division, reproductive cycles, sleep, and feeding. However, a second circadian system exists that can be entrained by meal feeding and has an influence over metabolism and behavior. Recent advances in the molecular genetics of circadian clocks are revealing clock characteristics such as rhythmic clock gene expression in a variety of non-neural tissues such as liver. Although little is known regarding the function of these clock genes in the liver, there is a large literature that addresses the capabilities of this organ to keep time. This time-keeping capability may be an adaptive function allowing for the prediction of mealtime and therefore improved digestion and energy usage. Consequently, an understanding of these rhythms is of great importance. This review summarizes the results of studies on diurnal and circadian rhythmicity in the rodent liver. We hope to lend support to the hypothesis that there are functionally important circadian clocks outside of the brain that are not light- or SCN-dependent. Rather, these clocks are largely responsive to stimuli involved in nutrient intake. The interaction between these two systems may be very important for the ability of organisms to synchronize their internal physiology. [source] Extra pair paternity in birds: a review of interspecific variation and adaptive functionMOLECULAR ECOLOGY, Issue 11 2002Simon C. Griffith Abstract The application of molecular genetic techniques has revolutionized our view of avian mating systems. Contrary to prior expectations, birds are only very rarely sexually monogamous, with ,extra-pair offspring' found in approximately 90% of species. Even among socially monogamous species, over 11% of offspring are, on average, the result of extra-pair paternity (EPP). Based on over 150 molecular genetic studies of EPP in birds, we review two topical areas: (i) ecological explanations for interspecific variation in the rate of EPP; and (ii) evidence bearing on the adaptive function of EPP. We highlight the remaining challenges of understanding the relative roles of genes and ecology in determining variation between taxa in the rate of extra paternity, and testing for differences between extra-pair offspring and those sired within-pair. [source] Child Development and Evolutionary PsychologyCHILD DEVELOPMENT, Issue 6 2000David F. Bjorklund Evolutionary developmental psychology involves the expression of evolved, epigenetic programs, as described by the developmental systems approach, over the course of ontogeny. There have been different selection pressures on organisms at different times in ontogeny, and some characteristics of infants and children were selected in evolution to serve an adaptive function at that time in their life history rather than to prepare individuals for later adulthood. Examples of such adaptive functions of immaturity are provided from infancy, play, and cognitive development. Most evolved psychological mechanisms are proposed to be domain specific in nature and have been identified for various aspects of children's cognitive and social development, most notably for the acquisition of language and for theory of mind. Differences in the quality and quantity of parental investment affect children's development and influence their subsequent reproductive and childcare strategies. Some sex differences observed in childhood, particularly as expressed during play, are seen as antecedents and preparations for adult sex differences. Because evolved mechanisms were adaptive to ancestral environments, they are not always adaptive for contemporary people, and this mismatch of evolved mechanisms with modern environments is seen in children's maladjustment to some aspects of formal schooling. We argue that an evolutionary perspective can be valuable for developing a better understanding of human ontogeny in contemporary society and that a developmental perspective is important for a better understanding of evolutionary psychology. [source] Differentiating normal, abnormal, and disordered personalityEUROPEAN JOURNAL OF PERSONALITY, Issue 4 2005W. John Livesley Interest in the interface between normality and psychopathology was renewed with the publication of DSM-III more than 20 years ago. The use of a separate axis to classify disorders of personality brought increased attention to these conditions. At the same time, the definition of personality disorder as inflexible and maladaptive traits stimulated interest in the relationship between normal and disordered personality structure and functioning. The evidence suggests that the traits delineating personality disorder are continuous with normal variation and that the structural relationships among these traits resemble the structures described by normative trait theories. Recognition that personality disorder represents the extremes of trait dimensions emphasizes the importance of differentiating normal, abnormal, and disordered personality. It is argued that while abnormal personality may be considered extreme variation, personality disorder is more than statistical variation. A definition of personality disorder is suggested based on accounts of the adaptive functions of personality. Copyright © 2005 John Wiley & Sons, Ltd. [source] Colour polymorphism in birds: causes and functionsJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 4 2003P. Galeotti Abstract We studied polymorphism in all species of birds that are presently known to show intraspecific variation in plumage colour. At least three main mechanisms have been put forward to explain the maintenance of polymorphism: apostatic, disruptive and sexual selection. All of them make partly different predictions. Our aims were to investigate evolutionary causes and adaptive functions of colour polymorphism by taking into account a number of ecological and morphological features of polymorphic species. Overall, we found 334 species showing colour polymorphism, which is 3.5% of all bird species. The occurrence of colour polymorphism was very high in Strigiformes, Ciconiiformes, Cuculiformes and Galliformes. Phylogenetically corrected analysis using independent contrasts revealed that colour polymorphism was maximally expressed in species showing a daily activity rhythm extended to day/night, living in both open and closed habitats. All these findings support the hypothesis that colour polymorphism probably evolved under selective pressures linked to bird detectability as affected by variable light conditions during activity period. Thus, we conclude that selective agents may be prey, predators and competitors, and that colour polymorphism in birds may be maintained by disruptive selection. [source] Diagnostic evaluation of developmental delay/mental retardation: An overviewAMERICAN JOURNAL OF MEDICAL GENETICS, Issue 1 2003Agatino Battaglia Abstract Mental retardation (MR) is one of the few clinically important disorders for which the etiopathogenesis is still poorly understood. It is a condition of great concern for public health and society. MR is currently defined as a significant impairment of cognitive and adaptive functions, with onset before age 18 years. It may become evident during infancy or early childhood as developmental delay (DD), but it is best diagnosed during the school years. MR is estimated to occur in 1,10% of the population, and research on its etiology has always been a challenge in medicine. The etiopathogenesis encompasses so many different entities that the attending physician can sometimes feel a "virtual panic," starting a wide-range diagnostic evaluation. The Consensus Conference of the American College of Medical Genetics has recently established guidelines regarding the evaluation of patients with MR [Curry et al., 1997], emphasizing the high diagnostic utility of cytogenetic studies and neuroimaging in certain clinical settings. However, since then there has been substantial progress in molecular cytogenetics and neuroimaging techniques, the use of which has allowed recognition and definition of new disorders, thus increasing the diagnostic yield. This review will focus on the most appropriate investigations shown to be, at present, necessary to define the etiology of DD/MR, in the context of recommendations for the clinical evaluation of the patient with undiagnosed MR. © 2003 Wiley-Liss, Inc. [source] Use of gene transfer technology for functional studies in grapevineAUSTRALIAN JOURNAL OF GRAPE AND WINE RESEARCH, Issue 2010J.R. VIDAL Abstract The understanding of the genetic determinism of plant phenotypes requires the functional annotation of genes governing specific traits including the characterisation of their regulatory networks. A striking feature of the grapevine genome and proteome lies in the existence of large families related to wine attributes that have a higher gene copy number than in other sequenced plants. During speciation, the appearance of new adaptive functions is often based on the evolution of orthologous genes eventually associated with duplication (paralogous sequences) leading to new proteins and expression profiles. The presence of original features in grapevine, including perennial status, vegetative architecture, inflorescence/tendril, flower organisation (corolla), and fleshy fruit of considerable acidity with various flavonoid compounds, makes functional genomics an essential approach to link a gene to a trait. For grapevine, the current lack of high throughput genetic techniques (e.g. induced mutant collections) and the difficulties associated with genetic mapping (allele diversity, chimerism, generation time) highlights the critical role of transgenic technology for characterising gene function. Different techniques are available to obtain information about gene functioning, but the choice of a particular approach depends on the process investigated (e.g. metabolism, developmental, pathogen response) and the experimental purpose (e.g. induction of ectopic functions, promoter studies, subcellular localisation). After a brief overview of the development of grapevine biotechnology, this paper reviews the state-of-the-art gene transfer technology for grapevine and detailed examples of where transgenic technology has proven useful for studying gene function. [source] Child Development and Evolutionary PsychologyCHILD DEVELOPMENT, Issue 6 2000David F. Bjorklund Evolutionary developmental psychology involves the expression of evolved, epigenetic programs, as described by the developmental systems approach, over the course of ontogeny. There have been different selection pressures on organisms at different times in ontogeny, and some characteristics of infants and children were selected in evolution to serve an adaptive function at that time in their life history rather than to prepare individuals for later adulthood. Examples of such adaptive functions of immaturity are provided from infancy, play, and cognitive development. Most evolved psychological mechanisms are proposed to be domain specific in nature and have been identified for various aspects of children's cognitive and social development, most notably for the acquisition of language and for theory of mind. Differences in the quality and quantity of parental investment affect children's development and influence their subsequent reproductive and childcare strategies. Some sex differences observed in childhood, particularly as expressed during play, are seen as antecedents and preparations for adult sex differences. Because evolved mechanisms were adaptive to ancestral environments, they are not always adaptive for contemporary people, and this mismatch of evolved mechanisms with modern environments is seen in children's maladjustment to some aspects of formal schooling. We argue that an evolutionary perspective can be valuable for developing a better understanding of human ontogeny in contemporary society and that a developmental perspective is important for a better understanding of evolutionary psychology. [source] |