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1.
Psychol Sport Exerc ; 71: 102588, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38159711

RESUMO

This study explored the experiences and perceptions of coaches, athletes, and integrated support teams towards the management of three Paralympic teams across North America and Europe. Six focus groups with athletes, three interviews with head coaches, and 10 interviews with support team members were conducted and analyzed using a reflexive thematic analysis. Our analysis resulted in three overarching themes to portray the coaches' role and behaviours in managing their (1) athletes, (2) integrated support teams, and (3) team as a collective unit. All teams were made up of a diverse group of athletes that required individualized considerations regarding age, finances, and disability. Coaches were successful when they fostered autonomy and managed interpersonal conflict by utilizing their integrated support teams to foster cohesiveness. This study provides an in-depth view of the role of the coach in managing national parasport teams by incorporating multiple perspectives from three teams around the world.


Assuntos
Atletas , Pessoas com Deficiência , Humanos , Relações Interpessoais , Europa (Continente) , Grupos Focais
2.
Psychol Sport Exerc ; 64: 102303, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-37665803

RESUMO

Partnering with a provincial coaching association in Canada, we explored the experiences and perceptions of 15 mentor and 29 mentee coaches who participated in a formal virtual parasport coach mentorship program. Data were gathered via focus groups and individual interviews and analyzed using a reflexive thematic analysis. Mentor coaches built a virtual relationship through mutual trust and respect and were perceived by their mentees as supportive, motivating, and knowledgeable. Mentee coaches valued conversations with their mentors surrounding disability-specific knowledge that enhanced their coaching efficacy. Coaches highlighted the need for a greater sense of community within parasport and recommended keeping a virtual component of the program to foster accessibility and learning. Findings provide insight into effective mentorship in parasport for researchers, practitioners, and organizations overseeing this important initiative. Our results will contribute to higher quality experiences for Canadian parasport coaches and athletes and work to progress the growth of parasport worldwide.


Assuntos
Tutoria , Mentores , Humanos , Canadá , Atletas , Comunicação
3.
Adapt Phys Activ Q ; 40(1): 105-125, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36220142

RESUMO

The majority of research on the coach-athlete relationship has been explored from the perspective of able-bodied athletes. The purpose of this study was to explore wheelchair basketball athletes' perceptions of the coach-athlete relationship. Timelining and semistructured interviews were conducted with six wheelchair basketball athletes, and data were analyzed using a reflexive thematic analysis. Athletes highlighted the important role that parasport coaches played in fostering an enjoyable wheelchair basketball environment and valued coaches who displayed expertise regarding their athletes' equipment and had personal parasport athletic experiences. Additionally, athletes identified personal preferences, including coaches who addressed sex differences and maintained professional relationships at the national level as contributing factors to the coach-athlete relationship. The current results benefit both parasport coaches and athletes by providing a portrayal of coaching behaviors, characteristics, and expertise that not only influence the parasport coach-athlete dyad but also affect the well-being and athletic development of parasport athletes.


Assuntos
Basquetebol , Tutoria , Paratletas , Humanos , Masculino , Feminino , Atletas
4.
Disabil Rehabil ; 44(22): 6824-6832, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-34613859

RESUMO

PURPOSE: Spinal cord injury (SCI) peer mentors are individuals who, through their lived experiences, offer emotional support and empathetic understanding to others living with SCI to foster positive health, independence, and well-being. This study explored SCI peer mentors' perceptions of their roles and experiences. MATERIALS AND METHODS: Six paid or volunteer peer mentors participated in semi-structured interviews. We first explored the data using thematic narrative analysis to identify patterns, themes, and narrative types. Next, we analyzed the narrative types using creative analytical practices to construct and refine the stories. RESULTS: Based on our analysis, we developed two stories from a storyteller perspective to present a snapshot of SCI peer mentors' experiences. The first story focuses on a "discovery" narrative from the point of view of Casey who adopted a person-centered approach to mentoring, focusing their attention on the needs of the mentee. The second story focuses on Taylor's experiences with the "dark" side of peer mentorship, which focuses on the psychological toll of being a SCI peer mentor, from discussions about suicidal thoughts with clients to struggling with burnout. CONCLUSIONS: Results provided insights for support services regarding the importance of supporting the mental health of mentors to ensure they continue delivering high quality mentorship.Implications for rehabilitationPeer mentors need to be educated on the significance of their role in the rehabilitation process and how their interpersonal behaviours can influence their mentees, both positively and negatively.Peer mentors should receive formalized and accessible training to ensure they are equipped with effective mentoring skills, but also providing them with tools to cope with physical, mental, and emotional stressors they may encounter as mentors.There is a need to continue diversifying and improving the types of services provided to SCI peer mentors in addition to one-on-one counselling, such as interactive educational workshops, for peer mentors to learn and practice coping skills, including mindfulness, meditation, and action-planning.As with other paid employees, SCI peer mentors should be trained to recognize when they are feeling depleted and be supported in seeking appropriate care from a health professional to provide quality psychosocial services to others.


Assuntos
Tutoria , Traumatismos da Medula Espinal , Humanos , Mentores/psicologia , Tutoria/métodos , Grupo Associado , Traumatismos da Medula Espinal/reabilitação
5.
Adapt Phys Activ Q ; 38(1): 109-137, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33296870

RESUMO

The purpose of this scoping review was to provide a broad overview of the literature pertaining to parasport coaches, including information regarding the size and scope of research, the populations and perspectives obtained, and the type of methods used to conduct the research. Data were collected and analyzed using a six-stage framework for conducting scoping reviews. The results revealed that the majority of articles were based on interviews, and an overwhelming majority of the participants were men coaching at the high-performance level in North America. Three of the most frequent topics were becoming a parasport coach, being a parasport coach, and having general parasport coaching knowledge. Articles ranged in date from 1991 to 2018, with 70% of empirical articles published from 2014 onward, indicating an emerging interest in this field of research. This review has the potential to advance the science and practice of parasport coaching at all levels.


Assuntos
Tutoria , Feminino , Humanos , Masculino
6.
Brain Res Bull ; 138: 88-95, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28899796

RESUMO

Evidence suggests that the addiction process may begin immediately in some vulnerable subjects. Specifically, some rats have been shown to exhibit aversive taste reactivity (gapes) following the intraoral delivery of a cocaine-predictive taste cue after as few as 1-2 taste-drug pairings. After only 3-4 trials, the number of gapes becomes a reliable predictor of later cocaine self-administration. Given that escalation of drug-taking behavior over time is recognized as a key feature of substance use disorder (SUD) and addiction, the present study examined the relationship between early aversion to the cocaine-predictive flavor cue and later escalation of cocaine self-administration in an extended-access paradigm. The data show that rats who exhibit the greatest conditioned aversion early in training to the intraorally delivered cocaine-paired cue exhibit the greatest escalation of cocaine self-administration over 15 extended-access trials. This finding suggests that early onset of the conditioned opponent process (i.e., the near immediate shift from ingestion to rejection of the drug-paired cue) is a reliable predictor of future vulnerability and resilience to cocaine addiction-like behavior. Future studies must determine the underlying neural mechanisms associated with this early transition and, hence, with early vulnerability to the later development of SUD and addiction. In so doing, we shall be in position to discover novel diagnostics and novel avenues of prevention and treatment.


Assuntos
Anestésicos Locais/administração & dosagem , Cocaína/administração & dosagem , Autoadministração , Paladar/efeitos dos fármacos , Administração Oral , Análise de Variância , Animais , Masculino , Ratos , Ratos Sprague-Dawley , Tempo de Reação/efeitos dos fármacos , Reflexo de Endireitamento/efeitos dos fármacos , Fatores de Tempo
7.
Brain Res Bull ; 138: 73-79, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28939474

RESUMO

The single nucleotide polymorphism of the µ-opioid receptor, OPRM1 A118G, has been associated with greater drug and alcohol use, increased sensitivity to pain, and reduced sensitivity to the antinociceptive effects of opiates. In the present studies, we employed a 'humanized' mouse model containing the wild-type (118AA) or variant (118GG) allele to examine behavior in a model of heroin-induced devaluation of an otherwise palatable saccharin cue when repeated saccharin-heroin pairings occurred every 24h (Experiment 1) or every 48h (Experiment 2). The results showed that, while both the 118AA and 118GG mice demonstrated robust avoidance of the heroin-paired saccharin cue following daily taste-drug pairings, only the 118AA mice suppressed intake of the heroin-paired saccharin cue when 48h elapsed between each taste-drug pairing. Humanized 118GG mice, then, defend their intake of the sweet cue despite saccharin-heroin pairings and this effect is illuminated by the use of spaced, rather than massed, trials. Given that this pattern of strain difference is not evident with saccharin-cocaine pairings (Freet et al., 2015), reduced avoidance of the heroin-paired saccharin cue by the 118GG mice may be due to an interaction between the opiate and the subjects' drive for the sweet or, alternatively, to differential downstream sensitivity to the aversive kappa mediated properties of the drug. These alternative hypotheses are addressed.


Assuntos
Analgésicos Opioides/farmacologia , Heroína/farmacologia , Polimorfismo de Nucleotídeo Único/genética , Receptores Opioides mu/genética , Sacarina/administração & dosagem , Edulcorantes/administração & dosagem , Análise de Variância , Animais , Aprendizagem por Associação/efeitos dos fármacos , Aprendizagem da Esquiva/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Peso Corporal/genética , Comportamento de Escolha/efeitos dos fármacos , Ritmo Circadiano/efeitos dos fármacos , Ritmo Circadiano/genética , Sinais (Psicologia) , Ingestão de Líquidos/efeitos dos fármacos , Ingestão de Líquidos/genética , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Receptores Opioides mu/metabolismo , Recompensa , Paladar
8.
Physiol Behav ; 167: 282-288, 2016 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-27640134

RESUMO

Iron deficiency (ID) is the most prevalent single-nutrient deficiency worldwide. There is evidence that ID early in development (preweaning in rat) causes irreversible neurologic, behavioral, and motor development deficits. Many of these effects have been attributed to damage to dopamine systems, including ID-induced changes in transporter and receptor numbers in the striatum and nucleus accumbens. These mesolimbic dopaminergic neurons are, in part, responsible for mediating reward and thus play a key role in addiction. However, there has been relatively little investigation into the behavioral effects of ID on drug addiction. In 2002, we found that rats made ID from weaning (postnatal day 21) and throughout the experiment acquired cocaine self-administration significantly more slowly than controls and failed to increase responding when the dose of the drug was decreased. In the present study, we assessed addiction for self-administered cocaine in rats with a history of preweaning ID only during postnatal days 4 through 21, and iron replete thereafter. The results showed that while ID did not affect the number of cocaine infusions or the overall addiction-like behavior score, ID rats scored higher on a measure of continued responding for drug than did iron replete controls. This increase in responding, however, was less goal-directed as ID rats also responded more quickly to the non-rewarded manipulandum than did control rats. Thus, while ID early in infancy did not significantly increase addiction-like behaviors for cocaine in this small study, the pattern of data suggests a possible underlying learning or performance impairment. Future studies will be needed to elucidate the exact neuro-behavioral deficits that lead to the increase in indiscriminate responding for drug in rats with a history of perinatal ID.


Assuntos
Comportamento Aditivo/fisiopatologia , Cocaína/administração & dosagem , Inibidores da Captação de Dopamina/administração & dosagem , Deficiências de Ferro , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Análise de Variância , Animais , Comportamento Aditivo/induzido quimicamente , Condicionamento Operante/efeitos dos fármacos , Condicionamento Operante/fisiologia , Relação Dose-Resposta a Droga , Feminino , Hemoglobinas/metabolismo , Masculino , Gravidez , Ratos , Ratos Sprague-Dawley , Tempo de Reação/efeitos dos fármacos , Tempo de Reação/fisiologia , Esquema de Reforço , Autoadministração
9.
Brain Res Bull ; 123: 53-60, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26562520

RESUMO

Chronic exposure to drugs and alcohol leads to damage to dopaminergic neurons and their projections in the 'reward pathway' that originate in the ventral tegmental area (VTA) and terminate in the nucleus accumbens (NAc). This damage is thought to contribute to the signature symptom of addiction: chronic relapse. In this study we show that bilateral transplants of human retinal pigment epithelial cells (RPECs), a cell mediated dopaminergic and trophic neuromodulator, into the medial shell of the NAc, rescue rats with a history of high rates of cocaine self-administration from drug-seeking when returned, after 2 weeks of abstinence, to the drug-associated chamber under extinction conditions (i.e., with no drug available). Excellent survival was noted for the transplant of RPECs in the shell and/or the core of the NAc bilaterally in all rats that showed behavioral recovery from cocaine seeking. Design based unbiased stereology of tyrosine hydroxylase (TH) positive cell bodies in the VTA showed better preservation (p<0.035) in transplanted animals compared to control animals. This experiment shows that the RPEC graft provides beneficial effects to prevent drug seeking in drug addiction via its effects directly on the NAc and its neural network with the VTA.


Assuntos
Transtornos Relacionados ao Uso de Cocaína/prevenção & controle , Epitélio Pigmentado da Retina/transplante , Transtornos Relacionados ao Uso de Substâncias/prevenção & controle , Animais , Cocaína/farmacologia , Condicionamento Operante/fisiologia , Dopamina/farmacologia , Neurônios Dopaminérgicos , Comportamento de Procura de Droga/fisiologia , Células Epiteliais , Extinção Psicológica/fisiologia , Humanos , Masculino , Núcleo Accumbens/metabolismo , Córtex Pré-Frontal/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Epitélio Pigmentado da Retina/metabolismo , Pigmentos da Retina , Recompensa , Autoadministração , Área Tegmentar Ventral/efeitos dos fármacos
10.
Brain Res Bull ; 123: 61-70, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26494018

RESUMO

The ability to predict individual vulnerability to substance abuse would allow for a better understanding of the progression of the disease and development of better methods for prevention and/or early intervention. Here we use drug-induced devaluation of a saccharin cue in an effort to predict later addiction-like behavior in a model akin to that used by Deroche-Gamonet et al. (2004) and seek to link such vulnerability to changes in expression of various mu opioid receptor and D2 receptor-interacting proteins in brain. The results show that the greatest heroin-induced suppression of intake of a saccharin cue is associated with the greatest vulnerability to later addiction-like behavior and to differences in the expression of WLS, ß-catenin, and NCS-1 in brain compared to rats that exhibited the least suppression of intake of the heroin-paired cue and/or saline controls. Finally, because the self-administration model employed produced no significant differences in drug intake between groups, overall, the resultant changes in protein expression can be more closely linked to individual differences in motivation for drug.


Assuntos
Dependência de Heroína/metabolismo , Dependência de Heroína/prevenção & controle , Heroína/metabolismo , Animais , Comportamento Animal/efeitos dos fármacos , Sinais (Psicologia) , Heroína/farmacologia , Masculino , Ratos , Ratos Sprague-Dawley , Receptores Opioides mu/metabolismo , Sacarina/administração & dosagem , Autoadministração , Paladar/fisiologia , Percepção Gustatória/fisiologia , beta Catenina/metabolismo
11.
Behav Neurosci ; 130(1): 103-13, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26653714

RESUMO

Rats suppress intake of a palatable taste cue when paired with a rewarding or an aversive stimulus in appetitive or aversive conditioning, respectively. A similar phenomenon occurs with drugs of abuse, but the nature of this conditioning has been subject for debate. While relatively little is known about the underlying neural circuitry, we recently reported bilateral lesions of the thalamic trigeminal orosensory area isolate drug-induced suppression of intake of a taste cue. The lesion blocks avoidance of the taste cue when paired with experimenter delivered drugs of abuse, yet has no effect on avoidance of the same cue when paired with an aversive agent or when it predicts access to a highly palatable sucrose solution. We hypothesize the lesion may blunt the rewarding properties of the drug. To test this, we used a runway apparatus, as running speed has been shown to increase with increasing reward value. Our hypothesis was supported by failure of the lesioned rats to increase running speed for morphine. Interestingly, lesioned rats did avoid intake of the drug-paired cue when presented in the runway apparatus and displayed naloxone-precipitated withdrawal. Using a partial crossover design, the lesion prevented avoidance of a cocaine-paired cue when presented in the home cage. We conclude that the lesion disrupts avoidance of a taste cue in anticipation of the rewarding properties of a drug but, at least in the presence of contextual cues, allows for avoidance of a taste cue as it elicits the onset of an aversive conditioned state of withdrawal.


Assuntos
Comportamento de Procura de Droga/fisiologia , Motivação/fisiologia , Percepção Gustatória/fisiologia , Paladar/fisiologia , Tálamo/lesões , Análise de Variância , Anestésicos Locais/farmacologia , Animais , Peso Corporal/efeitos dos fármacos , Cocaína/farmacologia , Condicionamento Psicológico , Comportamento de Procura de Droga/efeitos dos fármacos , Masculino , Motivação/efeitos dos fármacos , Naloxona/farmacologia , Antagonistas de Entorpecentes/farmacologia , Ratos , Ratos Sprague-Dawley , Recompensa , Sacarina/administração & dosagem , Estatística como Assunto , Edulcorantes/administração & dosagem , Paladar/efeitos dos fármacos , Percepção Gustatória/efeitos dos fármacos , Tálamo/efeitos dos fármacos
12.
Behav Neurosci ; 129(6): 744-55, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26501177

RESUMO

Drug overdose now exceeds car accidents as the leading cause of accidental death in the United States. Of those drug overdoses, a large percentage of the deaths are due to heroin and/or pharmaceutical overdose, specifically misuse of prescription opioid analgesics. It is imperative, then, that we understand the mechanisms that lead to opioid abuse and addiction. The rewarding actions of opioids are mediated largely by the mu-opioid receptor (MOR), and signaling by this receptor is modulated by various interacting proteins. The neurotransmitter dopamine also contributes to opioid reward, and opioid addiction has been linked to reduced expression of dopamine D2 receptors (D2R) in the brain. That said, it is not known if alterations in the expression of these proteins relate to drug exposure and/or to the "addiction-like" behavior exhibited for the drug. Here, we held total drug self-administration constant across acquisition and showed that reduced expression of the D2R and the MOR interacting protein, Wntless, in the medial prefrontal cortex was associated with greater addiction-like behavior for heroin in general and with a greater willingness to work for the drug in particular. In contrast, reduced expression of the D2R in the nucleus accumbens and hippocampus was correlated with greater seeking during signaled nonavailability of the drug. Taken together, these data link reduced expression of both the D2R and Wntless to the explicit motivation for the drug rather than to differences in total drug intake per se.


Assuntos
Comportamento de Procura de Droga/fisiologia , Heroína/administração & dosagem , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Motivação/efeitos dos fármacos , Entorpecentes/administração & dosagem , Receptores de Dopamina D2/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Animais , Comportamento Aditivo/metabolismo , Expressão Gênica/efeitos dos fármacos , Dependência de Heroína/metabolismo , Dependência de Heroína/psicologia , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Motivação/fisiologia , Núcleo Accumbens/efeitos dos fármacos , Núcleo Accumbens/metabolismo , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Ratos Sprague-Dawley , Recompensa , Autoadministração
13.
Physiol Behav ; 139: 216-23, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25449401

RESUMO

Several studies have shown that human carriers of the single nucleotide polymorphism of the µ-opioid receptor, OPRM1 A118G, exhibit greater drug and alcohol use, increased sensitivity to pain, and reduced sensitivity to the antinociceptive effects of opiates. In the present study, we employed a 'humanized' mouse model containing the wild-type (118AA) or variant (118GG) allele to examine behavior in our model of drug-induced suppression of a natural reward cue and to compare the morphine pharmacological profile in acutely isolated sensory neurons. Compared with 118AA mice, our results demonstrate that homozygous 118GG mice exhibit greater avoidance of the cocaine-paired saccharin cue, a behavior linked to an aversive withdrawal-like state. Electrophysiological recordings confirmed the reduced modulation of Ca(2+) channels by morphine in trigeminal ganglion (TG) neurons from 118GG mice compared to the 118AA control cells. However, repeated cocaine exposure in 118GG mice led to a leftward shift of the morphine concentration-response relationship when compared with 118GG control mice, while a rightward shift was observed in 118AA mice. These results suggest that cocaine exposure of mice carrying the 118G allele leads to a heightened sensitivity of the reward system and a blunted modulation of Ca(2+) channels by morphine in sensory neurons.


Assuntos
Cocaína/farmacologia , Inibidores da Captação de Dopamina/farmacologia , Ingestão de Alimentos/efeitos dos fármacos , Receptores Opioides mu/metabolismo , Sacarina/administração & dosagem , Células Receptoras Sensoriais/efeitos dos fármacos , Animais , Comportamento Aditivo/fisiopatologia , Canais de Cálcio/metabolismo , Células Cultivadas , Transtornos Relacionados ao Uso de Cocaína/fisiopatologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Ingestão de Alimentos/fisiologia , Humanos , Masculino , Camundongos Transgênicos , Polimorfismo de Nucleotídeo Único , Receptores Opioides mu/genética , Recompensa , Células Receptoras Sensoriais/fisiologia , Síndrome de Abstinência a Substâncias/fisiopatologia , Gânglio Trigeminal/efeitos dos fármacos , Gânglio Trigeminal/fisiologia
14.
Behav Neurosci ; 126(4): 538-50, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22687147

RESUMO

Substance abuse and addiction are associated with an apparent devaluation of, and inattention to, natural rewards. This consequence of addiction can be modeled using a reward comparison paradigm where rats avoid intake of a palatable taste cue that comes to predict access to a drug of abuse. Evidence suggests rats avoid intake following such pairings, at least in part, because the taste cue pales in comparison to the highly rewarding drug expected in the near future. In accordance, lesions of the gustatory thalamus or cortex eliminate avoidance of a taste cue when paired with either a drug of abuse or a rewarding sucrose solution, but not when paired with the aversive agent, LiCl. The present study used bilateral ibotenic acid lesions to evaluate the role of a neighboring thalamic structure, the trigeminal orosensory area (TOA), in avoidance of a gustatory cue when paired with sucrose (experiment 1), morphine (experiment 2), cocaine (experiment 3), or LiCl (experiment 4). The results show that the TOA lesion disrupts, but does not eliminate avoidance of a taste cue that predicts access to a preferred sucrose solution and leaves intact the development of a LiCl-induced conditioned taste aversion. The lesion does, however, eliminate the suppression of intake of a taste cue when paired with experimenter-administered morphine or cocaine using our standard parameters. As such, this is the first manipulation found to dissociate avoidance of a taste cue when mediated by a sweet or by a drug of abuse.


Assuntos
Aprendizagem por Associação/fisiologia , Aprendizagem da Esquiva/fisiologia , Recompensa , Paladar/fisiologia , Tálamo/lesões , Análise de Variância , Animais , Antimaníacos/farmacologia , Aprendizagem por Associação/efeitos dos fármacos , Aprendizagem da Esquiva/efeitos dos fármacos , Cocaína/administração & dosagem , Condicionamento Clássico/efeitos dos fármacos , Condicionamento Operante/efeitos dos fármacos , Condicionamento Operante/fisiologia , Inibidores da Captação de Dopamina/administração & dosagem , Ingestão de Alimentos/efeitos dos fármacos , Agonistas de Aminoácidos Excitatórios/toxicidade , Preferências Alimentares/efeitos dos fármacos , Ácido Ibotênico/toxicidade , Cloreto de Lítio/farmacologia , Masculino , Morfina/administração & dosagem , Ratos , Ratos Sprague-Dawley , Tempo de Reação/efeitos dos fármacos , Sacarina/administração & dosagem , Paladar/efeitos dos fármacos
15.
Sleep Med ; 11(3): 314-9, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20149726

RESUMO

BACKGROUND: Restless legs syndrome (RLS) is characterized by abnormal leg sensations and an uncontrollable urge to move the lower extremities during rest periods. Evidence suggests that reflex tasks that involve sensory-motor integration may be altered in RLS patients. This led us to determine if RLS patients show alterations in a sensory-motor reflex conditioning task called differential eyeblink conditioning. METHODS: RLS subjects were washed out of treatment medication for 7 days prior to testing. Subjects (20 RLS and 19 Control) received 120 discrimination conditioning trials consisting of 60 CS+ trials (i.e., an auditory stimulus paired with the airpuff-US separated by a silent 900 ms trace interval) and 60 CS- trials (i.e., a different auditory stimulus that was NOT paired with the US). RESULTS: Control subjects showed normal differential responding to the CS+ and CS-, but the RLS patients showed little or no differential responding. A post-test questionnaire provides evidence that symptomatic interference was not responsible for the eyeblink conditioning deficits in the RLS subjects, and further suggests that neurophysiological factors were responsible for these deficits. CONCLUSIONS: Together these results suggest that deficits in eyeblink conditioning are related to the pathophysiology of RLS. The eyeblink conditioning test may also be useful for supporting a clinical diagnosis or treatment strategy for RLS.


Assuntos
Condicionamento Palpebral/fisiologia , Síndrome das Pernas Inquietas/fisiopatologia , Adulto , Idoso , Análise de Variância , Estudos de Casos e Controles , Eletromiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tempo de Reação/fisiologia , Índice de Gravidade de Doença , Estatísticas não Paramétricas , Adulto Jovem
16.
J Nutr ; 140(3): 642-7, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20089786

RESUMO

Many studies have shown that perinatal nutritional iron deficiency (ID) produces learning impairments in children. Research has also shown that catecholamines like epinephrine and norepinephrine play a pivotal role in the consolidation of memories. In this study, we sought to determine if perinatal ID impairs the following: 1) noradrenergic synaptic function in the hippocampus; and 2) several forms of hippocampus-dependent fear learning. Electrophysiological brain slice methods were used to examine noradrenergic-mediated synaptic efficacy in the CA1-hippocampus of rats that were subjected to perinatal ID or control (CN) diets. Rats were fed ID (3 mg Fe/kg) or CN (45 mg Fe/kg) diets on gestational d 14. These diets were maintained until postnatal d (P) 12 after which all rats were switched to the CN diet. Hippocampal slices were prepared between P26 and P30. The noradrenergic agonist isoproterenol (ISO) (1, 2, or 4 micromol) was used to induce modulatory increases in synaptic efficacy in the hippocampal slices. CN slices showed a long-lasting increase in synaptic efficacy as the result of ISO perfusion in the slice bath, whereas ID slices did not show increases in synaptic efficacy as the result of ISO perfusion. ID and CN groups did not differ when ISO was perfused through slices from adult rats (P61). Both young and adult ID rats showed reduced levels of hippocampus-dependent fear learning compared with the young and adult CN rats. Together, these findings suggest that ID may impair early forms of noradrenergic-mediated synaptic plasticity, which may in turn play a role in adult learning deficits.


Assuntos
Hipocampo/fisiologia , Deficiências de Ferro , Ferro da Dieta , Animais , Dieta , Feminino , Memória , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Ratos
17.
Imagin Cogn Pers ; 29(4): 307-322, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-21031150

RESUMO

Studies have documented the negative effects of mental imagery on perception (also known as the Perky effect) in younger adults, but imagery-interference effects in older adults have never been assessed. Two experiments examined this issue directly. Experiment 1 demonstrated that visual mental images diminish visual acuity in younger adults (mean age = 19.0) but not older adults (mean age = 73.6). Experiment 2 obtained parallel results, showing that visual imagery interfered with performance on a visual detection task in younger (mean age = 18.7) but not older adults (mean age = 66.7). Processes underlying age-related differences in imagery-interference effects are discussed and implications of these results for changes in cognitive performance in older adults are considered.

18.
Dev Neurosci ; 30(4): 243-54, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-17962715

RESUMO

Studies show that iron deficient (ID) children are at risk for poor cognitive development. Research also shows that ID may impair the development of the skeletal motor abilities. The present study sought to determine if perinatal ID in rats impairs a motor learning task called eyeblink conditioning. This task used a hippocampus-dependent trace version or non-hippocampus-dependent delay version. Rats were placed on ID or control diets from gestational day (G) 12 to postnatal day (P) 12. Young rats (P32-29) subjected to perinatal ID showed severe impairments in trace eyeblink conditioning but only minor impairments in delay eyeblink conditioning. A young moderate ID group (ID from G12 to P2) was also impaired in trace eyeblink conditioning. The ID rats that became adults (P64-69) showed only minor impairments in trace eyeblink conditioning. Young ID rats showed no deficits in motoric ability on a separate rotorod learning test. This study suggests that perinatal ID impairs motoric learning by altering higher-order learning centers like the hippocampus more so than by altering the skeletal motor system.


Assuntos
Anemia Ferropriva/fisiopatologia , Piscadela/fisiologia , Hipocampo/fisiologia , Ferro da Dieta/farmacologia , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Reflexo Anormal/fisiologia , Fatores Etários , Animais , Peso Corporal , Condicionamento Palpebral/fisiologia , Ingestão de Alimentos , Feminino , Masculino , Leite , Atividade Motora/fisiologia , Gravidez , Ratos
19.
Br J Ophthalmol ; 91(2): 146-8, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17135337

RESUMO

BACKGROUND: Bupivacaine injected into animal muscles induces a cycle of myotoxicity, degeneration, regeneration and hypertrophy of muscle fibres, without adverse effects on other tissues. This induced hypertrophy can be harnessed to treat strabismus. METHODS: Bupivacaine, 4.5 ml of a 0.75% solution, was injected into the right lateral rectus (RLR) muscle of a patient who had diplopia and who showed 14-prism-dioptres oesotropia. RESULTS: RLR paresis persisted for 7 days. Then, the RLR regained its abducting ability, and progressive improvement of alignment to 4-prism-dioptres oesophoria occurred over the next 33 days, with the elimination of diplopia. Alignment remained the same at 54 days after injection. Magnetic resonance imaging showed a focal increase in the size of the injected RLR of 58% in the posterior area, with reduced change in anterior portions of the RLR. CONCLUSION: Injection of bupivacaine to induce hypertrophy of the injected muscle and thus alter eye alignment was effective in our patient. This approach can be a useful addition to the treatment of strabismus.


Assuntos
Anestésicos Locais/uso terapêutico , Bupivacaína/uso terapêutico , Estrabismo/tratamento farmacológico , Idoso , Diplopia/etiologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Músculos Oculomotores/patologia , Órbita/patologia , Estrabismo/complicações , Estrabismo/patologia
20.
J Vis ; 6(5): 616-24, 2006 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-16881792

RESUMO

Significant soft tissue features in the orbit and elsewhere are not resolved by MRI or any other imaging method. We describe a new method that uses tiny ( approximately 0.1 mm diameter) gold beads as markers to visualize movements of such tissues with high spatial resolution ( approximately 100 microm) and moderate temporal resolution ( approximately 100 ms). We describe bead fabrication, implantation, imaging, and image processing to extract three-dimensional bead coordinates. We then present results of an experiment to determine the stability of gold bead tissue markers (GBTMs) over time in normally moving orbital tissues. Most beads (76%) implanted in sclera, muscle, tendon, and connective tissue were highly stable over the 6-month measurement period. Beads that were judged unstable drifted only a few 100 microm. Bead flows with gaze suggested that posterior Tenon's capsule moves with the globe, that the lateral rectus belly may sideslip, producing "bridle forces," and that the posterior medial rectus pulley sling moves freely anteriorly and posteriorly, but hardly vertically, as required by the "coordinated active pulley" hypothesis. The GBTM method seems applicable to study such short time course phenomena as extraocular muscle (EOM) and connective tissue movement as a function of gaze and such long time course phenomena as myopic eye growth.


Assuntos
Ouro , Técnicas Histológicas , Microesferas , Animais , Tecido Conjuntivo , Estabilidade de Medicamentos , Desenho de Equipamento , Fixação Ocular/fisiologia , Ouro/administração & dosagem , Injeções/instrumentação , Macaca mulatta , Agulhas , Músculos Oculomotores/fisiologia , Órbita , Esclera , Tendões , Fatores de Tempo
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