Broad Age Range (broad + age_range)

Distribution by Scientific Domains


Selected Abstracts


Prolonged maturation of auditory perception and learning in gerbils

DEVELOPMENTAL NEUROBIOLOGY, Issue 9 2010
Emma C. Sarro
Abstract In humans, auditory perception reaches maturity over a broad age range, extending through adolescence. Despite this slow maturation, children are considered to be outstanding learners, suggesting that immature perceptual skills might actually be advantageous to improvement on an acoustic task as a result of training (perceptual learning). Previous non-human studies have not employed an identical task when comparing perceptual performance of young and mature subjects, making it difficult to assess learning. Here, we used an identical procedure on juvenile and adult gerbils to examine the perception of amplitude modulation (AM), a stimulus feature that is an important component of most natural sounds. On average, Adult animals could detect smaller fluctuations in amplitude (i.e., smaller modulation depths) than Juveniles, indicating immature perceptual skills in Juveniles. However, the population variance was much greater for Juveniles, a few animals displaying adult-like AM detection. To determine whether immature perceptual skills facilitated learning, we compared naïve performance on the AM detection task with the amount of improvement following additional training. The amount of improvement in Adults correlated with naïve performance: those with the poorest naïve performance improved the most. In contrast, the naïve performance of Juveniles did not predict the amount of learning. Those Juveniles with immature AM detection thresholds did not display greater learning than Adults. Furthermore, for several of the Juveniles with adult-like thresholds, AM detection deteriorated with repeated testing. Thus, immature perceptual skills in young animals were not associated with greater learning. © 2010 Wiley Periodicals, Inc. Develop Neurobiol 70: 636,648, 2010 [source]


Angiocentric glioma: A case report and review of the literature

DIAGNOSTIC CYTOPATHOLOGY, Issue 6 2010
Ryan T. Mott M.D.
Abstract Angiocentric glioma (AG) is a rare central nervous system (CNS) neoplasm that was only recently recognized by the World Health Organization (WHO). AG occurs in a broad age range, shows no gender predilection, and arises superficially in the cerebrum, usually resulting in medically intractable seizures. Most cases are cured by surgical excision alone, consistent with a WHO grade I neoplasm. We report a case of an AG in the right frontal lobe of a 57-year-old female, emphasizing the cytologic and immunohistochemical features, including confirmation and comparison with the surgical specimen. To our knowledge, this is the first report detailing the cytology of AG, including demonstration of important diagnostic findings that were only appreciated in the cytologic preparations and not in the smears or the surgical specimen. We also compare and contrast AG to other entities in the differential diagnosis and include a review of the literature. Diagn. Cytopathol. 2010. © 2009 Wiley-Liss, Inc. [source]


Trait anger and anger expression style in children's risky decisions

AGGRESSIVE BEHAVIOR, Issue 1 2009
Elisa Gambetti
Abstract In this study, 104 children completed a task, measuring risk decision-making, and the State-Trait Anger Expression Inventory for Children and Adolescents . Subjects were also asked to evaluate the degree of danger, benefit, fun and fear perceived for each risky choice. Analyses indicated that (a) risk decision-making was predicted by both trait anger and outward expression of anger; (b) appraisal of danger fully mediated the relationship between trait anger and risk; (c) perceptions of benefit, scare and fun partially mediated the relationship between trait anger and risk; and (d) appraisal of danger partially mediated the relationship between outward expression of anger and risk decision-making. The results provide evidence for a relationship between dispositional anger and risk decision-making during childhood, suggesting a possible explanation of the mechanisms below. In particular, risk decision-making can be viewed as the output of cognitive and emotive processes, linked to dispositional anger that leads children to be amused, optimistic and fearless in potentially risky situations. These findings substantiate the importance of incorporating cognitive and emotive factors in theories that seek to explain the relationship between personality traits and risk decision-making across a broad age range. Aggr. Behav. 35:14,23, 2009. © 2008 Wiley-Liss, Inc. [source]


Which duration of postsaccadic slowing identifies anticipatory saccades during smooth pursuit eye movements?

PSYCHOPHYSIOLOGY, Issue 2 2001
Randal G. Ross
Increased frequency of anticipatory saccades during smooth pursuit eye movements is a potential marker of genetic risk for schizophrenia. Postsaccadic slowing criteria are used to separate anticipatory from other types of saccades. However, the necessary duration of slowed pursuit required to identify an anticipatory saccade remains undetermined. We explored the effect of various postsaccadic slowing duration criteria on effect size in a comparison of younger and older schizophrenic and normal adults. For large anticipatory saccades, varying the duration of postsaccadic slowing criteria did not notably change effect size. For smaller leading saccades, a limited 50-ms duration postsaccadic slowing criterion produced the largest effect size (1.54), and maintained a similar effect size across a broad age range. Leading saccades with a limited duration postsaccadic slowing criteria are a possible marker of genetic risk for schizophrenia. [source]


Physiological determinants of the variation in left ventricular mass from early adolescence to late adulthood in healthy subjects

CLINICAL PHYSIOLOGY AND FUNCTIONAL IMAGING, Issue 4 2007
Peter A. Cain
Summary Background:, The physiological determinants of left ventricular mass (LVM) measured by cardiac magnetic resonance (CMR) imaging are not well defined as prior investigators have studied either adults or adolescents in isolation or have not strictly excluded hypertension or accounted for the effects of exercise habits, haemodynamic, demographic, or body shape characteristics. Methods:, Ninety-seven healthy volunteers (11,81 years, 51 males) underwent CMR. All parameters [unstandardized and adjusted for body surface area (BSA)] were analysed according to gender and by adolescence versus adulthood (adolescents <20 years, adults ,20 years). The influence of haemodynamic factors, exercise and demographic factors on LVM were determined with multivariate linear regression. Results:, Left ventricular mass rose during adolescence and declined in adulthood. LVM and LVMBSA were higher in males both in adults (LVM: 188 ± 22 versus 140 ± 21 g, P<0·001; LVMBSA: 94 ± 11 versus 80 ± 11 g m,2, P<0·001) and in adolescents when adjusted for BSA (LVM: 128 ± 29 versus 107 ± 20 g, P = 0·063; LVMBSA: 82 ± 8 versus 71 ± 10 g m,2, P = 0·025). In adults, systolic blood pressure (SBP) and self-reported physical activity increased while meridional and circumferential wall stress were constant with age. Multivariate regression analysis revealed age, gender and BSA as the major determinants of LVM (global R2 = 0·68). Conclusions:, Normal LVM shows variation over a broad age range in both genders with a rise in adolescence and subsequent decline with increasing age in adulthood despite an increase in SBP and physical activity. BSA, age and gender were found to be major contributors to the variation in LVM in healthy adults, while haemodynamic factors, exercise and wall stress were not. [source]