Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 38
Filtrar
1.
Cogn Res Princ Implic ; 8(1): 68, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37930437

RESUMO

When selecting fillers to include in a police lineup, one must consider the level of similarity between the suspect and potential fillers. In order to reduce misidentifications, an innocent suspect should not stand out. Therefore, it is important that the fillers share some degree of similarity. Importantly, increasing suspect-filler similarity too much will render the task too difficult reducing correct identifications of a guilty suspect. Determining how much similarity yields optimal identification performance is the focus of the proposed study. Extant research on lineup construction has provided somewhat mixed results. In part, this is likely due to the subjective nature of similarity, which forces researchers to define similarity in relative terms. In the current study, we manipulate suspect-filler similarity via a multidimensional scaling model constructed using objective facial measurements. In doing so, we test the "propitious heterogeneity" and the diagnostic-feature-detection hypotheses which predict an advantage of lineups with low-similarity fillers in terms of discriminability. We found that filler similarity did not affect discriminability. We discuss limitations and future directions.


Assuntos
Excipientes , Face , Humanos , Culpa , Análise de Escalonamento Multidimensional , Polícia
2.
Mem Cognit ; 51(6): 1404-1415, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36849759

RESUMO

Prior research has shown that searching for multiple targets in a visual search task enhances distractor memory in a subsequent recognition test. Three non-mutually exclusive accounts have been offered to explain this phenomenon. The mental comparison hypothesis states that searching for multiple targets requires participants to make more mental comparisons between the targets and the distractors, which enhances distractor memory. The attention allocation hypothesis states that participants allocate more attention to distractors because a multiple-target search cue leads them to expect a more difficult search. Finally, the partial match hypothesis states that searching for multiple targets increases the amount of featural overlap between targets and distractors, which necessitates greater attention in order to reject each distractor. In two experiments, we examined these hypotheses by manipulating visual working memory (VWM) load and target-distractor similarity of AI-generated faces in a visual search (i.e., RSVP) task. Distractor similarity was manipulated using a multidimensional scaling model constructed from facial landmarks and other metadata of each face. In both experiments, distractors from multiple-target searches were recognized better than distractors from single-target searches. Experiment 2 additionally revealed that increased target-distractor similarity during search improved distractor recognition memory, consistent with the partial match hypothesis.


Assuntos
Face , Reconhecimento Facial , Memória , Modelos Neurológicos , Reconhecimento Facial/fisiologia , Face/anatomia & histologia , Humanos , Masculino , Feminino , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Modelos Psicológicos , Atenção/fisiologia , Reconhecimento Psicológico/fisiologia , Memória/fisiologia , Reprodutibilidade dos Testes
3.
Cogn Res Princ Implic ; 7(1): 95, 2022 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-36271974

RESUMO

When selecting fillers to include in a police lineup, one must consider the level of similarity between the suspect and potential fillers. In order to reduce misidentifications, an innocent suspect should not stand out. Therefore, it is important that the fillers share some degree of similarity. Importantly, increasing suspect-filler similarity too much will render the task too difficult reducing correct identifications of a guilty suspect. Determining how much similarity yields optimal identification performance is the focus of the proposed study. Extant research on lineup construction has provided somewhat mixed results. In part, this is likely because similarity is often defined in relative terms due to the subjective nature of similarity. In the current study, we propose an experiment in which we manipulate suspect-filler similarity via a multidimensional scaling model constructed using objective facial measurements. In doing so, we test the "propitious heterogeneity" and the diagnostic-feature-detection hypotheses which predict an advantage of lineups with low similarity fillers in terms of discriminability.


Assuntos
Rememoração Mental , Reconhecimento Psicológico , Humanos , Crime , Culpa , Polícia
4.
Cogn Res Princ Implic ; 7(1): 55, 2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35763165

RESUMO

There is an increasing need in eyewitness identification research to identify factors that not only influence identification accuracy but may also impact the confidence-accuracy (CA) relationship. One such variable that has a notable impact on memory for faces is viewing distance, with faces encoded from a shorter distance remembered better than faces encoded at longer differences. In four pre-registered experiments, using both laboratory and online samples, we compared faces viewed at a simulated viewing distance at two different levels (medium and far) to faces that were viewed at a very near-simulated distance. Distance was simulated using a Gaussian blur function with higher levels of blur corresponding to greater simulated distance. We found that both medium and far simulated distances impaired memory performance overall relative to no simulated distance, with increased distance resulting in poorer memory. However, only far simulated distances impaired the CA relationship. In a fourth experiment, we found that a pre-test warning did not ameliorate this impairment of the CA relationship for faces viewed at a far simulated distance. These findings suggest that even high-confidence identifications made for faces viewed from long distances should be disregarded, and that estimator variables that impact memory may degrade the CA relationship when memory is reduced to critical levels.


Assuntos
Cognição , Rememoração Mental , Humanos , Hiperplasia
5.
Br J Radiol ; 94(1118): 20201000, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33180553

RESUMO

OBJECTIVES: To evaluate segmented diffusion tensor imaging (DTI) white matter tract fractional anisotropy (FA) and mean diffusivity (MD) values in acute cervical spinal cord injury (CSCI). METHODS: 15 patients with acute CSCI and 12 control subjects were prospectively recruited and underwent axial DTI as part of the spine trauma MRI. Datasets were put through a semi-automated probabilistic segmentation algorithm that analyzed white matter, motor and sensory tracts. FA and MD values were calculated for white matter, sensory (spinal lemniscal) and motor tracts (ventral/lateral corticospinal) at the level of clinical injury, levels remote from injury and in normal controls. RESULTS: There were significant differences in FA between the level of injury and controls for total white matter (0.65 ± .09 vs 0.68 ± .07; p = .044), motor tracts (0.64 ± .07 vs 0.7 ± .09; p = .006), and combined motor/sensory tracts (0.63 ± .09 vs 0.69 ± .08; p = .022). In addition, there were significant FA differences between the level of injury and one level caudal to the injury for combined motor tracts (0.64 ± .07 vs 0.69 ± .05; p = .002) and combined motor/sensory tracts (0.63 ± .09 vs 0.7 ± .07; p = .011). There were no significant differences for MD between the level of injury and one level caudal to the injury or normal controls. CONCLUSION: Abnormalities in DTI metrics of DTI-segmented white matter tracts were detected at the neurological level of injury relative to normal controls and levels remote from the injury site, confirming its value in CSCI assessment. ADVANCES IN KNOWLEDGE: Segmented DTI analysis can help identify microstructural spinal cord abnormalities in the setting of traumatic cervical spinal cord injury.


Assuntos
Imagem de Tensor de Difusão/métodos , Traumatismos da Medula Espinal/diagnóstico por imagem , Doença Aguda , Adulto , Medula Cervical/diagnóstico por imagem , Estudos de Avaliação como Assunto , Feminino , Humanos , Masculino , Estudos Prospectivos
6.
J Immunol Methods ; 488: 112904, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33121975

RESUMO

BACKGROUND: Indirect immunofluorescence (IIF) is the most prevalent screening antinuclear antibody test for systemic autoimmune rheumatic disease (SARD). Certain IIF patterns have known antibody and disease associations, but the dense fine speckled (ANA-DFS) pattern has no confirmed clinical associations. Our objective was to determine the prevalence of SARD among a group of ANA-DFS positive individuals and to identify final diagnoses among non-SARD individuals in order to determine possible clinical associations with the ANA-DFS pattern. METHODS: A retrospective study of 425 patients from a university health care system with a positive ANA-DFS pattern consecutively between August 2017 and September 2018. Sera samples underwent ANA testing by IIF on HEp-2 cell substrates (Euroimmun, Germany). Clinical information was retrieved from electronic health records and stored in a de-identified database. RESULTS: The prevalence of SARD was 24%. Undetermined diagnosis (17%), skin disorders (12.1%), and fibromyalgia/chronic pain syndrome/chronic fatigue syndrome (11.8%) were the most common non-SARD diagnoses. Taking into account past medical history, the most common non-SARD were atopic disorders (21.2%), fibromyalgia/chronic pain syndrome/chronic fatigue syndrome (17.6%), and skin disorders (16.7%). CONCLUSIONS: The ANA-DFS pattern may be indicative of an underlying antigen-antibody interaction that plays a role in either the initiation or propagation of immunologic reactions. DFS70/LEDGF is a transcription factor involved in cell survival and stress protection, and autoantibodies may inhibit its function. It is likely that there are other antibodies producing the ANA-DFS pattern besides anti-DFS70/LEDGF, and more research is necessary to identify additional antibody specificities. The ANA-DFS pattern may be an indicator of a proinflammatory microenvironment given the high frequency of symptomatic patients and disease processes with an immunologic basis (including SARD).


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/imunologia , Anticorpos Antinucleares/sangue , Doenças Autoimunes/diagnóstico , Microambiente Celular , Técnica Indireta de Fluorescência para Anticorpo , Doenças Reumáticas/diagnóstico , Testes Sorológicos , Fatores de Transcrição/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças Autoimunes/sangue , Doenças Autoimunes/epidemiologia , Doenças Autoimunes/imunologia , Biomarcadores/sangue , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prevalência , Reprodutibilidade dos Testes , Estudos Retrospectivos , Doenças Reumáticas/sangue , Doenças Reumáticas/epidemiologia , Doenças Reumáticas/imunologia , Estudos Soroepidemiológicos , Adulto Jovem
7.
Memory ; 28(8): 957-967, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32723219

RESUMO

Do students learn better with material that is perceptually hard to process? While evidence is mixed, recent claims suggest that placing materials in Sans Forgetica, a perceptually difficult-to-process typeface, has positive impacts on student learning. Given the weak evidence for other similar perceptual disfluency effects, we examined the mnemonic effects of Sans Forgetica more closely in comparison to other learning strategies across three preregistered experiments. In Experiment 1, participants studied weakly related cue-target pairs with targets presented in either Sans Forgetica or with missing letters (e.g., cue: G_RL, the generation effect). Cued recall performance showed a robust effect of generation, but no Sans Forgetica memory benefit. In Experiment 2, participants read an educational passage about ground water with select sentences presented in either Sans Forgetica typeface, yellow pre-highlighting, or unmodified. Cued recall for select words was better for pre-highlighted information than an unmodified pure reading condition. Critically, presenting sentences in Sans Forgetica did not elevate cued recall compared to an unmodified pure reading condition or a pre-highlighted condition. In Experiment 3, individuals did not have better discriminability for Sans Forgetica relative to a fluent condition in an old-new recognition test. Our findings suggest that Sans Forgetica really is forgettable.


Assuntos
Sinais (Psicologia) , Aprendizagem , Rememoração Mental , Leitura , Humanos
8.
Memory ; 28(4): 582-587, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32270739

RESUMO

Research suggests testing improves the retention of previously learned information. Here, we examined whether this might be due (in part) to the fact that tests help learners stay on task during the review stages of learning. In two experiments, participants encoded a list of words and later had an opportunity to review the material via a free recall test or re-reading the words. During review, participants provided self-reports as to whether their minds were on or off task. Results from both experiments show testing decreased mind-wandering. Importantly, this reduction in mind-wandering was associated with improved performance on a final memory test. These results suggest the mnemonic benefits associated with testing may stem not only from act of retrieval itself, but also from the fact that taking tests encourages a more efficient and engaged review of the material.


Assuntos
Atenção , Aprendizagem , Humanos , Memória , Rememoração Mental , Autorrelato
9.
Memory ; 26(10): 1460-1466, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29938582

RESUMO

Researchers generally agree that retrieval practice of previously learned material facilitates subsequent recall of same material, a phenomenon known as the testing effect. There is debate, however, about when such benefits transfer to related (though not identical) material. The current study examines the phenomenon of transfer in the domain of analogical problem-solving. In Experiments 1 and 2, learners were presented a source text describing a problem and solution to read which was subsequently either restudied or recalled. Following a short (Experiment 1) or long (Experiment 2) delay, learners were given a new target text and asked to solve a problem. The two texts shared a common structure such that the provided solution for the source text could be applied to solve the problem in the target text. In a combined analysis of both experiments, learners in the retrieval practice condition were more successful at solving the problem than those in the restudy condition. Experiment 3 explored the degree to which retrieval practice promotes cued versus spontaneous transfer by manipulating whether participants were provided with an explicit hint that the source and target texts were related. Results revealed no effect of retrieval practice.


Assuntos
Aprendizagem/fisiologia , Rememoração Mental/fisiologia , Resolução de Problemas , Transferência de Experiência , Adulto , Sinais (Psicologia) , Feminino , Humanos , Masculino
10.
Curr Probl Diagn Radiol ; 47(4): 257-269, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28869104

RESUMO

Although diffusion-weighted imaging (DWI) has become a mainstay in modern brain imaging, it remains less utilized in the evaluation of the spinal cord. Many studies have shown promise in using DWI and diffusion-tensor imaging (DTI) for evaluation of the spinal cord; however, application has been stalled by technical obstacles and artifacts, and questions remain regarding its clinical utility on an individual examination level. This review discusses the background, concepts, and technical aspects of DWI and DTI, specifically for imaging of the spinal cord. The clinical and investigational applications of spinal cord DTI, as well as the practical difficulties and limitations of DWI and DTI for the evaluation of the spinal cord are examined.


Assuntos
Imagem de Tensor de Difusão/métodos , Doenças da Medula Espinal/diagnóstico por imagem , Medula Espinal/diagnóstico por imagem , Anisotropia , Humanos , Aumento da Imagem , Interpretação de Imagem Assistida por Computador
11.
J Exp Psychol Learn Mem Cogn ; 44(5): 752-763, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29094992

RESUMO

Although memory retrieval often enhances subsequent memory, Peterson and Mulligan (2013) reported conditions under which retrieval produces poorer subsequent recall-the negative testing effect. The item-specific-relational account proposes that the effect occurs when retrieval disrupts interitem organizational processing relative to the restudy condition. Rawson et al. (2015), in contrast, failed to replicate the negative testing effect despite repeated high-powered attempts. This article examines the discrepant results, ruling out differences in procedures, and concludes that differences in participant population produced the varying outcome. Specifically, participants from the University of North Carolina (UNC) and Kent State University (KSU) completed the same version of the negative-testing paradigm and were assessed on several measures of cognitive ability (working memory capacity, Raven's progressive matrices, and SAT or ACT score). For the UNC sample, free recall scores and the amount of category clustering (a measure of organizational processing) was greater in the restudy than retrieval condition (i.e., the negative testing effect was found); for the KSU sample, there was no difference on either measure. Furthermore, in the restudy condition, recall and clustering was greater for UNC than KSU students whereas in the retrieval condition, there was no effect of site on either measure. As expected, measures of cognitive ability were greater for the UNC than KSU sample. The results indicate that the negative testing effect is replicable but is subject to limitation related to the participant population. An analysis in terms of the relationship between cognitive ability and memory predicted this pattern of results. (PsycINFO Database Record


Assuntos
Aprendizagem por Associação/fisiologia , Sinais (Psicologia) , Rememoração Mental/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Prática Psicológica , Psicologia Experimental/métodos , Leitura , Projetos de Pesquisa , Adulto , Humanos , Adulto Jovem
12.
Front Neuroinform ; 11: 63, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29163119

RESUMO

The contribution of this paper is to identify and describe current best practices for using Amazon Web Services (AWS) to execute neuroimaging workflows "in the cloud." Neuroimaging offers a vast set of techniques by which to interrogate the structure and function of the living brain. However, many of the scientists for whom neuroimaging is an extremely important tool have limited training in parallel computation. At the same time, the field is experiencing a surge in computational demands, driven by a combination of data-sharing efforts, improvements in scanner technology that allow acquisition of images with higher image resolution, and by the desire to use statistical techniques that stress processing requirements. Most neuroimaging workflows can be executed as independent parallel jobs and are therefore excellent candidates for running on AWS, but the overhead of learning to do so and determining whether it is worth the cost can be prohibitive. In this paper we describe how to identify neuroimaging workloads that are appropriate for running on AWS, how to benchmark execution time, and how to estimate cost of running on AWS. By benchmarking common neuroimaging applications, we show that cloud computing can be a viable alternative to on-premises hardware. We present guidelines that neuroimaging labs can use to provide a cluster-on-demand type of service that should be familiar to users, and scripts to estimate cost and create such a cluster.

13.
J Nat Sci ; 3(4)2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28670621

RESUMO

Before and after computerized writing instruction, participants completed assessment with normed measures and DTI and fMRI connectivity scanning. Evidence-based differential diagnosis was used at time 1 to assign them to diagnostic groups: typical oral and written language (n=6), dysgraphia (impaired handwriting, n=10), dyslexia (impaired word spelling and reading, n=20), and OWL LD (impaired syntax construction, n=6). The instruction was aimed at subword letter writing, word spelling, and syntax composing. With p <.001 to control for multiple comparisons, the following significant findings were observed in academic achievement, DTI (radial diffusivity RD, axial diffusivity AD, and mean diffusivity MD), and graph cluster coefficients for fMRI connectivity. A time effect (pre-post intervention increase) in handwriting and oral construction of sentence syntax was significant; but diagnostic group effects were significant for dictated spelling and creation of word-specific spellings, with the dyslexia and OWL LD groups scoring lower than the typical control or dysgraphia groups. For RD a time effect occurred in anterior corona radiata and superior frontal. For AD a time effect occurred in superior corona radiata, superior frontal region, middle frontal gyrus, and superior longitudinal fasciculus. For MD a time effect occurred in the same regions as AD and also anterior coronal radiata. A diagnostic group effect occurred for graph cluster coefficients in fMRI connectivity while writing the next letter in alphabet from memory; but the diagnostic group × time interaction was not significant. The only significant time × treatment interaction occurred in right inferior frontal gyrus associated with orthographic coding. Compared to time 1, cluster coefficients increased at time 2 in all groups except in the dysgraphia group in which they decreased. Implications of results are discussed for response to instruction (RTI) versus evidence-based differential diagnosis for identifying students with SLDs in writing which may be best understood at both the behavioral and brain levels of analysis.

14.
Front Neurol ; 8: 118, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28424656

RESUMO

As diffusion tensor imaging gains widespread use, many researchers have been motivated to go beyond the tensor model and fit more complex diffusion models, to gain a more complete description of white matter microstructure and associated pathology. Two such models are diffusion kurtosis imaging (DKI) and diffusion basis spectrum imaging (DBSI). It is not clear which DKI parameters are most closely related to DBSI parameters, so in the interest of enabling comparisons between DKI and DBSI studies, we conducted an empirical survey of the interrelation of these models in 12 healthy volunteers using the same diffusion acquisition. We found that mean kurtosis is positively associated with the DBSI fiber ratio and negatively associated with the hindered ratio. This was primarily driven by the radial component of kurtosis. The axial component of kurtosis was strongly and specifically correlated with the restricted ratio. The joint spatial distributions of DBSI and DKI parameters are tissue-dependent and stable across healthy individuals. Our contribution is a better understanding of the biological interpretability of the parameters generated by the two models in healthy individuals.

15.
Front Neuroinform ; 11: 17, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28270762

RESUMO

Correction of echo planar imaging (EPI)-induced distortions (called "unwarping") improves anatomical fidelity for diffusion magnetic resonance imaging (MRI) and functional imaging investigations. Commonly used unwarping methods require the acquisition of supplementary images during the scanning session. Alternatively, distortions can be corrected by nonlinear registration to a non-EPI acquired structural image. In this study, we compared reliability using two methods of unwarping: (1) nonlinear registration to a structural image using symmetric normalization (SyN) implemented in Advanced Normalization Tools (ANTs); and (2) unwarping using an acquired field map. We performed this comparison in two different test-retest data sets acquired at differing sites (N = 39 and N = 32). In both data sets, nonlinear registration provided higher test-retest reliability of the output fractional anisotropy (FA) maps than field map-based unwarping, even when accounting for the effect of interpolation on the smoothness of the images. In general, field map-based unwarping was preferable if and only if the field maps were acquired optimally.

16.
Behav Brain Res ; 325(Pt A): 17-24, 2017 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-28235586

RESUMO

Neonatal quinpirole (NQ) treatment to rats increases dopamine D2 receptor sensitivity persistent throughout the animal's lifetime. In Experiment 1, we analyzed the role of α7 and α4ß2 nicotinic receptors (nAChRs) in nicotine behavioral sensitization and on the brain-derived neurotrophic factor (BDNF) response to nicotine in NQ- and neonatally saline (NS)-treated rats. In Experiment 2, we analyzed changes in α7 and α4ß2 nAChR density in the nucleus accumbens (NAcc) and dorsal striatum in NQ and NS animals sensitized to nicotine. Male and female Sprague-Dawley rats were neonatally treated with quinpirole (1mg/kg) or saline from postnatal days (P)1-21. Animals were given ip injections of either saline or nicotine (0.5mg/kg free base) every second day from P33 to P49 and tested on behavioral sensitization. Before each injection, animals were ip administered the α7 nAChR antagonist methyllycaconitine (MLA; 2 or 4mg/kg) or the α4ß2 nAChR antagonist dihydro beta erythroidine (DhßE; 1 or 3mg/kg). Results revealed NQ enhanced nicotine sensitization that was blocked by DhßE. MLA blocked the enhanced nicotine sensitization in NQ animals, but did not block nicotine sensitization. NQ enhanced the NAcc BDNF response to nicotine which was blocked by both antagonists. In Experiment 2, NQ enhanced nicotine sensitization and enhanced α4ß2, but not α7, nAChR upregulation in the NAcc. These results suggest a relationship between accumbal BDNF and α4ß2 nAChRs and their role in the behavioral response to nicotine in the NQ model which has relevance to schizophrenia, a behavioral disorder with high rates of tobacco smoking.


Assuntos
Plasticidade Neuronal/efeitos dos fármacos , Nicotina/administração & dosagem , Agonistas Nicotínicos/administração & dosagem , Transtornos Psicóticos/metabolismo , Quimpirol/administração & dosagem , Receptores Nicotínicos/metabolismo , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Corpo Estriado/metabolismo , Modelos Animais de Doenças , Feminino , Masculino , Atividade Motora/efeitos dos fármacos , Núcleo Accumbens/metabolismo , Ratos Sprague-Dawley
17.
J Psychopharmacol ; 31(1): 75-85, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27940499

RESUMO

This study analyzed the interaction of adolescent methylphenidate on the behavioral response to nicotine and the effects of these drug treatments on brain-derived neurotrophic factor in the nucleus accumbens and hippocampus in male and female Sprague-Dawley rats. Animals were intraperitoneal administered 1 mg/kg methylphenidate or saline using a "school day" regimen (five days on, two days off) beginning on postnatal day (P)28 and throughout behavioral testing. In Experiment 1, animals were intraperitoneal administered 0.5 mg/kg (free base) nicotine or saline every second day for 10 days from P45-P63 and tested after a three-day drug washout on the forced swim stress task on P67-P68. Results revealed that adolescent methylphenidate blunted nicotine behavioral sensitization. However, methylphenidate-treated rats given saline during sensitization demonstrated decreased latency to immobility and increased immobility time on the forced swim stress task in males that was reduced by nicotine. In Experiment 2, a different set of animals were conditioned to nicotine (0.6 mg/kg free base) or saline using the conditioned place preference behavioral paradigm from P44-P51, and given a preference test on P52. On P53, the nucleus accumbens and hippocampus were analyzed for brain-derived neurotrophic factor. Methylphenidate enhanced nicotine-conditioned place preference in females and nicotine produced conditioned place preference in males and females pre-exposed to saline in adolescence. In addition, methylphenidate and nicotine increased nucleus accumbens brain-derived neurotrophic factor in females and methylphenidate enhanced hippocampus brain-derived neurotrophic factor in males and females. Methylphenidate adolescent exposure using a clinically relevant dose and regimen results in changes in the behavioral and brain-derived neurotrophic factor responses to nicotine in adolescence that are sex-dependent.


Assuntos
Comportamento Animal/efeitos dos fármacos , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Metilfenidato/farmacologia , Nicotina/farmacologia , Fatores Etários , Animais , Feminino , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Núcleo Accumbens/efeitos dos fármacos , Núcleo Accumbens/metabolismo , Gravidez , Ratos , Ratos Sprague-Dawley , Caracteres Sexuais
18.
Front Neuroinform ; 10: 2, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26869916

RESUMO

The contribution of this paper is to describe how we can program neuroimaging workflow using Make, a software development tool designed for describing how to build executables from source files. A makefile (or a file of instructions for Make) consists of a set of rules that create or update target files if they have not been modified since their dependencies were last modified. These rules are processed to create a directed acyclic dependency graph that allows multiple entry points from which to execute the workflow. We show that using Make we can achieve many of the features of more sophisticated neuroimaging pipeline systems, including reproducibility, parallelization, fault tolerance, and quality assurance reports. We suggest that Make permits a large step toward these features with only a modest increase in programming demands over shell scripts. This approach reduces the technical skill and time required to write, debug, and maintain neuroimaging workflows in a dynamic environment, where pipelines are often modified to accommodate new best practices or to study the effect of alternative preprocessing steps, and where the underlying packages change frequently. This paper has a comprehensive accompanying manual with lab practicals and examples (see Supplemental Materials) and all data, scripts, and makefiles necessary to run the practicals and examples are available in the "makepipelines" project at NITRC.

19.
Curr Top Behav Neurosci ; 29: 387-402, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26472551

RESUMO

This mini review focuses on the importance of the dopamine D2-like receptor family and its importance in psychosis. Past findings from this laboratory along with collaborators have been that neonatal quinpirole (a dopamine D2-like receptor agonist) results in increases in dopamine D2 receptor sensitivity that persists throughout the animal's lifetime. Findings from this model have been shown to have particular application and validity to schizophrenia, but may have broader implications toward other psychoses, which is reviewed in the present manuscript. In the present review, we also highlight other models of psychoses that have been centered on the subchronic administration of quinpirole to rats in order to model certain psychoses, which has uncovered some interesting and valid behavioral findings. This review highlights the importance of the combination of behavioral findings and neurobiological mechanisms focusing on neural plasticity in discovering underlying pathologies in these disorders that may lead to treatment discoveries, as well as the value of animal models across all psychoses.

20.
J Am Acad Child Adolesc Psychiatry ; 54(11): 938-46, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26506584

RESUMO

OBJECTIVE: Sexual dimorphism is evident in attention-deficit/hyperactivity disorder (ADHD), including subtype prevalence, adverse outcomes, and neural phenotype. Neurobiological studies of ADHD suggest that boys show more abnormalities in motor and premotor structure and function, whereas girls differ from typically developing (TD) peers in prefrontal circuitry. We applied diffusion tensor imaging (DTI) to identify ADHD-related sex-specific differences in motor/premotor and prefrontal white matter (WM) microstructure in children. METHOD: DTI estimated differences in WM microstructure among 120 children 8 to 12 years of age, 60 with ADHD (30 boys and 30 girls) and 60 controls (30 boys and 30 girls), matched on age, IQ, and handedness. Effects of diagnosis and sex on fractional anisotropy (FA) were assessed in motor/premotor and prefrontal regions. Group differences in FA and associations with response control (e.g., reaction time variability [CVRT] and commission error rate) were examined separately within sex. RESULTS: Sex-by-diagnosis interactions were observed for FA in primary motor (M1) and medial orbitofrontal (MOFC) cortex. Post hoc tests revealed that boys with ADHD showed bilateral reductions in FA within M1, compared with TD peers; in contrast, girls with ADHD showed higher FA bilaterally within MOFC. Decreased M1 FA was associated with higher CVRT in boys and higher commission error rates in girls. For MOFC, lower FA was associated with greater CVRT and commission error rates across all participants with ADHD. CONCLUSION: ADHD affects the white matter of boys and girls differently; boys appear to be more affected in regions responsible for control of basic actions, whereas girls show more abnormalities in regions responsible for higher-level, top-down control.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Lobo Frontal/patologia , Caracteres Sexuais , Substância Branca/patologia , Anisotropia , Escala de Avaliação Comportamental , Estudos de Casos e Controles , Criança , Manual Diagnóstico e Estatístico de Transtornos Mentais , Imagem de Tensor de Difusão , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Escalas de Graduação Psiquiátrica , Tempo de Reação
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...