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1.
Psychiatry Res ; 293: 113477, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33198048

RESUMO

The aim of the present study was to examine the relationship between sensory processing sensitivity (SPS) and symptoms of Attention Deficit Hyperactivity Disorder (ADHD) in adults. The Highly Sensitive Person Scale (HSPS) scale and the Adult ADHD Self-Report Scale (ASRS) were administered to a non-clinical group of 274 participants recruited from a university volunteers list. We found a highly significant positive correlation between number of self-reported ADHD traits and sensory sensitivity. Furthermore, ADHD traits and age were predictors of SPS and exploratory factor analysis revealed a factor that combined ADHD traits and items from the HSPS. The psychometric properties of the HSPS were also examined supporting the unidimensional nature of the concept. To our knowledge, this is the first study to identify a positive relationship between HSPS and ADHD traits in the general population. Our results further support recent findings suggesting abnormal sensory processing in ADHD.

2.
Front Psychol ; 11: 559883, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33192823

RESUMO

In the present study, we examined, for the first time, the association between self-disgust, loneliness, and mental health difficulties in war veterans diagnosed with PTSD. For this purpose, we used a mixed methods design, incorporating surveys and a novel eye-tracking paradigm, and compared the findings from the PTSD veteran group (n = 19) to those from a general population group (n = 22). Our results showed that the PTSD veteran group reported almost three times higher scores in self-disgust, and significantly higher scores in loneliness and mental health difficulties (anxiety and depression), compared to the general population. Furthermore, self-disgust mediated the association between loneliness and anxiety symptoms in both groups. The results from the eye-tracking paradigm further showed that veterans with PTSD displayed a self-avoidance gaze pattern, by looking significantly more toward pictures of faces of unknown others and away from their own face-a pattern that was not replicated in the general population group. Higher self-disgust scores were significantly associated with longer total gaze to the pictures of others (vs. the self). Our findings have implications for the role of self-disgust in the mental health of war veterans.

3.
Med Hypotheses ; 144: 110048, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32758886

RESUMO

Evidence suggests that 24.5%-46.7% (mean 31%) of patients with Parkinson's disease experience an anxiety disorder, a much higher prevalence than in controls. Anxiety does not appear to be a consequence of diagnosis or the motoric symptoms of the disorder and can manifest as Generalised Anxiety Disorder, phobias or panic attacks. At present, the neural underpinnings of anxiety disorders in Parkinson's disease is unknown. Here, we make the novel proposal that the superior colliculus (SC), one component of a rapid, reflexive threat detection system in the brain, consisting of the colliculus, pulvinar and amygdala, becomes hyper-responsive to sensory stimuli following dopamine denervation of the striatum in Parkinson's disease. This in turn leads to heightened responses to existing threat-related stimuli (giving rise to phobias and panic attacks), and heightened responses to anticipated threats (giving rise to Generalised Anxiety Disorder). This proposal is supported by a range of evidence, in particular elevated visual responses in the SC in an animal model of Parkinson's disease and in Parkinson's disease itself. Also facilitated saccadic eye movements (prosaccades, express saccades and fixational saccades) and increased distractibility in Parkinson's disease, both of which involve the SC. Identifying one potential locus of change in the brain in Parkinson's disease relevant to anxiety gives a potential target for interventions to combat a non-motor symptom that has a substantial negative effect on quality of life in the disorder.

4.
J Affect Disord ; 266: 646-654, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32056941

RESUMO

BACKGROUND: Self-disgust has been associated with loneliness and mental health difficulties in clinical and non-clinical populations, but there is limited research on the role of self-disgust in loneliness and mental health outcomes in older adults. METHODS: In Study 1 (N = 102; M age = 68.4 years, SD = 10.9, 68% females) we used a cross-sectional survey to explore the association between loneliness, self-disgust and mental health outcomes. In Study 2 (N = 80; M age = 68.8 years, SD = 11.4, 57% females) we used eye-tracking to investigate attentional vigilance, maintenance and avoidance in individuals with high (vs. low) self-disgust. RESULTS: In study 1 we found that self-disgust mediated the associations of loneliness with anxiety and depressive symptoms, and in study 2 it was demonstrated that older adults with high (vs. low) self-disgust displayed attentional avoidance to their own faces, compared to the faces of unknown others, a process that may perpetuate loneliness. LIMITATIONS: The cross-sectional design used in Study 1 limits our potential to make causal inferences. Additionally, both studies included a wide age range of older adults. CONCLUSIONS: Our findings are novel and highlight the importance of self-disgust experiences in the context of loneliness and mental health outcomes in older adults. Implications for practice and interventions against loneliness in this age group are discussed.

5.
Front Behav Neurosci ; 14: 7, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32082128

RESUMO

There is a current dispute over the origins, incidence, and development of Positivity Bias, i.e., preferential processing of positive relative to negative information. We addressed this question using a multi-method technique of behavioral, psychometric and event-related potential (ERP) measures in a lexical decision task (LDT). Twenty-four university students (11 female) participated (age range 18-26), but four were omitted owing to data issues. Participants were classified as Positivity Biased (PB) if their LDT responses to positive words were faster than negative words, and vice versa for those classified as Negativity Biased (NB), leading to a group of 11 PB participants and a group of 9 NB participants. Interestingly, the PB group was significantly faster overall than the NB group and had significantly shorter P2 component ERP latencies in the left occipital region. Furthermore, the PB group had significantly higher scores for expressive suppression (ES), together with higher scores for Crystallized Knowledge and for cognitive reappraisal (CR). These results suggest that around 55% of the students had Positivity Bias, and these were more efficient in processing information and had better emotion regulation abilities than those with a Negativity Bias.

6.
J Behav Med ; 43(3): 377-390, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31865486

RESUMO

Disgust-driven stigma may be motivated by an assumption that a stigmatized target presents a disease threat, even in the absence of objective proof. Accordingly, even non-contagious diseases, such as cancer, can become stigmatized by eliciting disgust. This study had two parts: a survey (n = 272), assessing the association between disgust traits and cancer stigma; and an experiment, in which participants were exposed to a cancer surgery (n = 73) or neutral video (n = 68), in order to test a causal mechanism for the abovementioned association. Having a higher proneness to disgust was associated with an increased tendency to stigmatize people with cancer. Further, a significant causal pathway was observed between disgust propensity and awkwardness- and avoidance-based cancer stigma via elevated disgust following cancer surgery exposure. In contrast, those exposed to cancer surgery not experiencing elevated disgust reported less stigma than controls. Exposure-based interventions, which do not elicit disgust, may be profitable in reducing cancer stigma.

7.
Med Hypotheses ; 133: 109407, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31586811

RESUMO

Attention Deficit Hyperactivity Disorder (ADHD) is one of the most common childhood behavioural disorders, the frontline treatments for which are drugs with abuse potential. As a consequence, there is an urgent need to develop non addictive drug treatments with equivalent efficacy. Preclinical evidence suggests that selective serotonin uptake inhibitors (SSRIs) are likely to be effective in ADHD, however clinical reports suggest that SSRIs are of limited therapeutic value for the treatment of ADHD. We propose that this disconnect can be explained by the pattern of drug administration in existing clinical trials (administration for short periods of time, or intermittently) leading to inadequate control of the autoregulatory processes which control 5-HT release, most notably at the level of inhibitory 5-HT1A somatodendritic autoreceptors. These autoreceptors reduce the firing rate of 5-HT neurons (limiting release) unless they are desensitised by a long term, frequent pattern of drug administration. As such, we argue that the participants in earlier trials were not administered SSRIs in a manner which realises any potential benefits of targeting 5-HT in the pharmacotherapy of ADHD. In light of this, we hypothesise that there may be under-researched potential to exploit 5-HT transmission therapeutically in ADHD, either through changing the administration regime, or by pharmacological means. Recent pharmacological research has successfully potentiated the effects of SSRIs in acute animal preparations by antagonising inhibitory 5-HT1A autoreceptors prior to the administration of the SSRI fluoxetine. We suggest that combination therapies linking SSRIs and 5-HT1A antagonists are a potential way forward in the development of efficacious non-addictive pharmacotherapies for ADHD.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Inibidores de Captação de Serotonina/uso terapêutico , Colículos Superiores/fisiopatologia , Animais , Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Ensaios Clínicos como Assunto/métodos , Dioxanos/administração & dosagem , Dioxanos/uso terapêutico , Esquema de Medicação , Sinergismo Farmacológico , Quimioterapia Combinada , Humanos , Pindolol/farmacologia , Pindolol/uso terapêutico , Piperazinas/administração & dosagem , Piperazinas/uso terapêutico , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos , Receptor 5-HT1A de Serotonina/fisiologia , Movimentos Sacádicos/fisiologia , Neurônios Serotoninérgicos/efeitos dos fármacos , Neurônios Serotoninérgicos/fisiologia , Serotonina/fisiologia , Antagonistas do Receptor 5-HT1 de Serotonina/administração & dosagem , Antagonistas do Receptor 5-HT1 de Serotonina/farmacologia , Antagonistas do Receptor 5-HT1 de Serotonina/uso terapêutico , Inibidores de Captação de Serotonina/administração & dosagem , Inibidores de Captação de Serotonina/farmacologia , Colículos Superiores/efeitos dos fármacos
8.
PLoS One ; 14(10): e0223663, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31618239

RESUMO

Parkinson's disease (PD) is associated with deficits in the recognition and expression of basic emotions, although self-reported levels of the self-conscious emotions shame and embarrassment are higher. However, one self-conscious emotion-self-disgust-which has been shown to have a negative impact on psychological wellbeing, has not been investigated in PD before. Here we employed self-report measures of self-conscious emotions, and an emotion induction paradigm involving images of the self, and narrated personal vignettes of instances when patients with PD (and controls) found themselves disgusting. We found that self-reported and induced levels of self-disgust were higher in PD patients than in matched controls, and that trait self-disgust was specifically related to disorders of impulse control in PD patients. Given the link between self-disgust and impaired psychological wellbeing, and the prevalence of anxiety and depression in PD, self-disgust might make a useful therapeutic target for psychological interventions in the condition.


Assuntos
Asco , Doença de Parkinson/psicologia , Autorrelato , Estudos de Casos e Controles , Emoções , Feminino , Humanos , Masculino , Estimulação Luminosa , Reconhecimento Psicológico , Análise de Regressão
9.
J Atten Disord ; 23(12): 1407-1415, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28800716

RESUMO

Objective: ADHD and autism spectrum disorder (ASD) can be viewed as the extreme end of traits found in the general population. Clinical and genetic studies suggest that ADHD and ASD often co-occur and share genetic susceptibility. The aim of this study was to examine co-occurrence of ADHD and ASD traits in the general population. Method: In total, 334 participants were recruited from a population-based sample. Four questionnaires assessing current and retrospective ADHD and ASD traits were administered online: the Adult ADHD Self-Report Scale (ASRS) Symptom Checklist, the Wender Utah Rating Scale (WURS-25), the Broad Autism Phenotype Questionnaire (BAPQ), and the Autism Spectrum Quotient (AQ). Results: A significant correlation was found between ADHD and autistic traits. In particular, higher inattention and overall ADHD scores were associated with self-reported deficits in communication and social skills. Conclusion: Our findings are similar to results from studies on clinical populations, suggesting that ADHD and ASD might share common etiology.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Transtorno do Espectro Autista , Adulto , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Transtorno do Espectro Autista/epidemiologia , Comorbidade , Humanos , Fenótipo , Estudos Retrospectivos , Utah
10.
Body Image ; 27: 109-117, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30243123

RESUMO

Self-disgust is an emotion schema negatively affecting people's body image and is triggered by bodily imperfections and deviations from the "normal" body envelope. In this study, we explore the idea that "normalising" the body in those with limb amputations via the prosthesis would be linked to reduced self-directed disgust. An international clinical community sample (N = 83) with mostly lower limb amputations completed measures about their demographics, prosthesis, adjustment, body image disturbance, psychological distress, and self-directed disgust in a survey design. Consistent with the "normalising" hypothesis, correlation and bootstrapped regression models revealed, first, that frequency of prosthesis use was significantly and negatively associated with physical self-disgust. Second, prosthesis use significantly mediated the exogenous effect of time since amputation on physical self-disgust. These results emphasise the psychological value of the prosthesis beyond its functional use, and stress its importance in normalising the body envelope in those with limb amputations, which may in turn promote psychological well-being.


Assuntos
Amputados/psicologia , Membros Artificiais , Imagem Corporal/psicologia , Asco , Adolescente , Adulto , Idoso , Amputação/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
11.
Elife ; 72018 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-30149836

RESUMO

Pain is a prevalent symptom of Parkinson's disease, and is effectively treated by deep brain stimulation of the subthalamic nucleus (STN). However, the link between pain and the STN remains unclear. In the present work, using in vivo electrophysiology in rats, we report that STN neurons exhibit complex tonic and phasic responses to noxious stimuli. We also show that nociception is altered following lesions of the STN, and characterize the role of the superior colliculus and the parabrachial nucleus in the transmission of nociceptive information to the STN, physiologically from both structures and anatomically in the case of the parabrachial nucleus. We show that STN nociceptive responses are abnormal in a rat model of PD, suggesting their dependence on the integrity of the nigrostriatal dopaminergic system. The STN-linked nociceptive network that we reveal is likely to be of considerable clinical importance in neurological diseases involving a dysfunction of the basal ganglia.


Assuntos
Rede Nervosa/fisiopatologia , Nociceptividade/fisiologia , Dor/fisiopatologia , Núcleo Subtalâmico/fisiopatologia , Animais , Biomarcadores/metabolismo , Modelos Animais de Doenças , Fenômenos Eletrofisiológicos , Masculino , Núcleos Parabraquiais/fisiopatologia , Doença de Parkinson/fisiopatologia , Tempo de Reação , Colículos Superiores
12.
Neuropharmacology ; 138: 118-129, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29879408

RESUMO

Heightened distractibility is a core symptom of Attention Deficit Hyperactivity Disorder (ADHD). Effective treatment is normally with chronic orally administered psychostimulants including amphetamine. Treatment prevents worsening of symptoms but the site of therapeutic processes, and their nature, is unknown. Mounting evidence suggests that the superior colliculus (SC) is a key substrate in distractibility and a therapeutic target, so we assessed whether therapeutically-relevant changes are induced in this structure by chronic oral amphetamine. We hypothesized that amphetamine would alter visual responses and morphological measures. Six-week old healthy male rats were treated with oral amphetamine (2, 5 or 10 mg/kg) or a vehicle for one month after which local field potential and multiunit recordings were made from the superficial layers of the SC in response to whole-field light flashes in withdrawal. Rapid Golgi staining was also used to assess dendritic spines, and synaptophysin staining was used to assess synaptic integrity. Chronic amphetamine increased local field potential responses at higher doses, and increased synaptophysin expression, suggesting enhanced visual input involving presynaptic remodelling. No comparable increases in multiunit activity were found suggesting amphetamine suppresses collicular output activity, counterbalancing the increased input. We also report, for the first time, five different dendritic spine types in the superficial layers and show these to be unaffected by amphetamine, indicating that suppression does not involve gross postsynaptic structural alterations. In conclusion, we suggest that amphetamine produces changes at the collicular level that potentially stabilise the structure and may prevent the worsening of symptoms in disorders like ADHD.


Assuntos
Anfetamina/farmacologia , Estimulantes do Sistema Nervoso Central/farmacologia , Colículos Superiores/efeitos dos fármacos , Percepção Visual/efeitos dos fármacos , Administração Oral , Animais , Atenção/efeitos dos fármacos , Atenção/fisiologia , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Espinhas Dendríticas/efeitos dos fármacos , Espinhas Dendríticas/fisiologia , Relação Dose-Resposta a Droga , Masculino , Ratos , Colículos Superiores/citologia , Colículos Superiores/fisiologia , Transmissão Sináptica/efeitos dos fármacos , Transmissão Sináptica/fisiologia , Sinaptofisina/metabolismo , Percepção Visual/fisiologia
13.
J Psychopharmacol ; 32(8): 949-954, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29580130

RESUMO

BACKGROUND: The phenomenon of locomotor sensitization to injected amphetamine is well-characterised. The increased locomotor activity found acutely is enhanced with repeated intermittent treatment. This effect arises due to hypersensitization of the dopaminergic system and is linked to drug addiction. A clinical population exposed to chronic repeated intermittent amphetamine treatment, such as is found for attention deficit hyperactivity disorder (ADHD), may be expected to be more at risk of addiction following this treatment. However, evidence suggests the opposite may be true. This suggests the route of administration may determine the direction of effects. AIMS AND METHODS: We aimed to establish how an oral amphetamine treatment regimen, similar to that used in ADHD, impacts on locomotor activity, specifically whether tolerance or sensitization would arise. Healthy hooded Lister rats were given amphetamine (2 mg/kg, 5 mg/kg and 10 mg/kg) or a vehicle solution once daily for 4 weeks with a 5 day on, 2 day off schedule. Locomotor activity was measured on the first day of treatment to establish the acute effects and on the final day of treatment to examine the chronic effects. RESULTS: As expected, acute doses of amphetamine increased locomotor activity, although this only reached statistical significance for the 5 mg/kg and 10 mg/kg doses. By contrast, after chronic treatment, animals administered these doses showed reduced activity indicating drug tolerance rather than sensitization had occurred. CONCLUSION: We suggest that the route of administration used in ADHD, which results in more stable and longer duration drug levels in the blood, results in tolerance rather than sensitization and that this effect could explain the reduced likelihood of substance addiction in those treated with psychostimulants for ADHD.


Assuntos
Anfetamina/administração & dosagem , Estimulantes do Sistema Nervoso Central/administração & dosagem , Tolerância a Medicamentos/fisiologia , Locomoção/efeitos dos fármacos , Administração Oral , Animais , Dopamina/metabolismo , Masculino , Atividade Motora/efeitos dos fármacos , Ratos
14.
Behav Brain Res ; 343: 1-7, 2018 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-29407411

RESUMO

Distractibility can be defined as an attention deficit where orientation toward irrelevant targets cannot be inhibited. There is now mounting evidence that the superior colliculus is a key neural correlate of distractibility, with increased collicular-activity resulting in heightened distractibility. Heightened distractibility is reduced by amphetamine, which acutely suppresses collicular responsiveness. However, when amphetamine is used to treat distractibility, it is given chronically, yet no data exist on whether chronic amphetamine treatment affects the colliculus. Here, the effect of chronic amphetamine treatment was assessed in healthy hooded lister rats on two collicular dependent behaviours following a twenty-eight day treatment period: i) orienting to visual stimuli, and ii) height-dependent modulation of air-righting. We found no significant impact of amphetamine treatment on visual orienting despite showing dose-dependent decreases in orienting to repeated stimuli. However, we did find that treatment with amphetamine significantly reduced the ability to modulate righting according to the height the animal is dropped from - a function known to be dependent on the colliculus. We suggest that the results are in line with previous research showing acute amphetamine suppresses collicular activity and we speculate that the psychostimulant may increase receptive field size, altering time-to-impact calculations carried out by the colliculus during air-righting.


Assuntos
Transtornos Relacionados ao Uso de Anfetaminas/fisiopatologia , Anfetamina/toxicidade , Estimulantes do Sistema Nervoso Central/toxicidade , Orientação/efeitos dos fármacos , Teto do Mesencéfalo/efeitos dos fármacos , Percepção Visual/efeitos dos fármacos , Animais , Atenção/efeitos dos fármacos , Atenção/fisiologia , Masculino , Orientação/fisiologia , Ratos , Reflexo de Endireitamento/efeitos dos fármacos , Reflexo de Endireitamento/fisiologia , Método Simples-Cego , Teto do Mesencéfalo/fisiopatologia , Percepção Visual/fisiologia
15.
Compr Psychiatry ; 80: 179-185, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29121555

RESUMO

Preliminary studies in children and adults with Attention Deficit Hyperactivity Disorder (ADHD) report both hypo-responsiveness and hyper-responsiveness to sensory stimuli, as well as problems modulating sensory input. As it has been suggested that those with ADHD exist at the extreme end of a continuum of ADHD traits, which are also evident in the general population, we investigated the link between ADHD and sensory sensitivity in the general population. Two online questionnaires measuring ADHD traits and sensory responsivity across various sensory domains were administered to 234 participants. Results showed a highly significant positive correlation between the number of ADHD traits and the frequency of reported sensory processing problems. An increased number of sensory difficulties across all modalities were associated with the level of ADHD. Furthermore, ADHD traits predicted sensory difficulties and exploratory factor analysis revealed a factor that combined ADHD trait and sensory processing items. This is the first study to identify a positive relationship between sensory processing and ADHD traits in the general population. Our results suggest that sensory difficulties could be part of the ADHD phenotype.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Vigilância da População , Transtornos das Sensações/diagnóstico , Transtornos das Sensações/epidemiologia , Adolescente , Adulto , Idoso , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Vigilância da População/métodos , Autorrelato , Sensação , Transtornos das Sensações/psicologia , Inquéritos e Questionários , Reino Unido/epidemiologia , Adulto Jovem
16.
J Clin Psychol Med Settings ; 24(3-4): 355-364, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29164511

RESUMO

The aim of this study was to explore quantitatively the relationship between disgust responses in cancer patients and their partners, and in turn their relationship to patients' psychological well-being. We recruited 50 participants with heterogeneous cancer diagnoses and their partners from cancer-related groups (e.g., charities). Patients completed questionnaires to determine levels of disgust propensity, disgust sensitivity, self-disgust, and symptoms of anxiety and depression. Disgust propensity and sensitivity were also assessed in their partners. Partners' disgust sensitivity was significantly positively correlated with cancer patients' self-disgust, disgust propensity, and depression. Path analyses suggested that patients' self-disgust plays a role in mediating the effect of partners' disgust sensitivity on patients' psychological well-being. This study provides the first quantitative evidence that psychological well-being in cancer patients is contingent on their partners' sensitivity to disgust, and that patients' self-disgust plays a mediating role. Focusing therapeutically on disgust responses could well be beneficial to people with cancer.


Assuntos
Emoções , Neoplasias/psicologia , Qualidade de Vida/psicologia , Cônjuges/psicologia , Adulto , Idoso , Transtornos de Ansiedade/diagnóstico , Transtornos de Ansiedade/psicologia , Transtorno Depressivo/diagnóstico , Transtorno Depressivo/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Autoimagem , Estatística como Assunto , Inquéritos e Questionários
17.
Acta Psychol (Amst) ; 181: 10-17, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29024843

RESUMO

Abnormalities in multimodal processing have been found in many developmental disorders such as autism and dyslexia. However, surprisingly little empirical work has been conducted to test the integrity of multisensory integration in Attention Deficit Hyperactivity Disorder (ADHD). The main aim of the present study was to examine links between symptoms of ADHD (as measured using a self-report scale in a healthy adult population) and the temporal aspects of multisensory processing. More specifically, a Simultaneity Judgement (SJ) and a Temporal Order Judgement (TOJ) task were used in participants with low and high levels of ADHD-like traits to measure the temporal integration window and Just-Noticeable Difference (JND) (respectively) between the timing of an auditory beep and a visual pattern presented over a broad range of stimulus onset asynchronies. The Point of Subjective Similarity (PSS) was also measured in both cases. In the SJ task, participants with high levels of ADHD-like traits considered significantly fewer stimuli to be simultaneous than participants with high levels of ADHD-like traits, and the former were found to have significantly smaller temporal windows of integration (although no difference was found in the PSS in the SJ or TOJ tasks, or the JND in the latter). This is the first study to identify an abnormal temporal integration window in individuals with ADHD-like traits. Perceived temporal misalignment of two or more modalities can lead to distractibility (e.g., when the stimulus components from different modalities occur separated by too large of a temporal gap). Hence, an abnormality in the perception of simultaneity could lead to the increased distractibility seen in ADHD.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Percepção Auditiva , Detecção de Sinal Psicológico , Percepção do Tempo , Percepção Visual , Adulto , Atenção , Feminino , Humanos , Julgamento , Masculino , Pessoa de Meia-Idade , Tempo de Reação , Autorrelato , Análise e Desempenho de Tarefas , Adulto Jovem
18.
Front Comput Neurosci ; 11: 62, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28798678

RESUMO

The striatum is the primary input nucleus for the basal ganglia, and receives glutamatergic afferents from the cortex. Under the hypothesis that basal ganglia perform action selection, these cortical afferents encode potential "action requests." Previous studies have suggested the striatum may utilize a mutually inhibitory network of medium spiny neurons (MSNs) to filter these requests so that only those of high salience are selected. However, the mechanisms enabling the striatum to perform clean, rapid switching between distinct actions that form part of a learned action sequence are still poorly understood. Substance P (SP) and enkephalin are neuropeptides co-released with GABA in MSNs preferentially expressing D1 or D2 dopamine receptors respectively. SP has a facilitatory effect on subsequent glutamatergic inputs to target MSNs, while enkephalin has an inhibitory effect. Blocking the action of SP in the striatum is also known to affect behavioral transitions. We constructed phenomenological models of the effects of SP and enkephalin, and integrated these into a hybrid model of basal ganglia comprising a spiking striatal microcircuit and rate-coded populations representing other major structures. We demonstrated that diffuse neuropeptide connectivity enhanced the selection of unordered action requests, and that for true action sequences, where action semantics define a fixed structure, a patterning of the SP connectivity reflecting this ordering enhanced selection of actions presented in the correct sequential order and suppressed incorrect ordering. We also showed that selective pruning of SP connections allowed context-sensitive inhibition of specific undesirable requests that otherwise interfered with selection of an action group. Our model suggests that the interaction of SP and enkephalin enhances the contrast between selection and rejection of action requests, and that patterned SP connectivity in the striatum allows the "chunking" of actions and improves selection of sequences. Efficient execution of action sequences may therefore result from a combination of ordered cortical inputs and patterned neuropeptide connectivity within striatum.

19.
J Psychopharmacol ; 31(7): 861-872, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28675114

RESUMO

Nicotine is a psychoactive substance that is commonly consumed in the context of music. However, the reason why music and nicotine are co-consumed is uncertain. One possibility is that nicotine affects cognitive processes relevant to aspects of music appreciation in a beneficial way. Here we investigated this possibility using Event-Related Potentials. Participants underwent a simple decision-making task (to maintain attentional focus), responses to which were signalled by auditory stimuli. Unlike previous research looking at the effects of nicotine on auditory processing, we used complex tones that varied in pitch, a fundamental element of music. In addition, unlike most other studies, we tested non-smoking subjects to avoid withdrawal-related complications. We found that nicotine (4.0 mg, administered as gum) increased P2 amplitude in the frontal region. Since a decrease in P2 amplitude and latency is related to habituation processes, and an enhanced ability to disengage from irrelevant stimuli, our findings suggest that nicotine may cause a reduction in habituation, resulting in non-smokers being less able to adapt to repeated stimuli. A corollary of that decrease in adaptation may be that nicotine extends the temporal window during which a listener is able and willing to engage with a piece of music.


Assuntos
Córtex Cerebral/efeitos dos fármacos , Potenciais Evocados Auditivos/efeitos dos fármacos , Habituação Psicofisiológica/efeitos dos fármacos , Nicotina/farmacologia , Agonistas Nicotínicos/farmacologia , Nível de Percepção Sonora/efeitos dos fármacos , Adolescente , Adulto , Eletroencefalografia , Feminino , Humanos , Masculino , Música , Nicotina/administração & dosagem , Agonistas Nicotínicos/administração & dosagem , Adulto Jovem
20.
Psychol Health ; 32(1): 19-37, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27615058

RESUMO

OBJECTIVES: Evidence suggests that disgust responses, known to negatively affect psychological wellbeing, may differ in people with cancer. We performed the first quantitative investigation of three discrete types of disgust trait - disgust propensity, sensitivity and self-directed disgust - in people diagnosed with a broad range of cancers (versus cancer-free controls), and explored their associations with psychological wellbeing. DESIGN: In a cross-sectional survey design, 107 participants with heterogeneous cancer diagnoses, recruited from cancer charities and support groups, were matched with cancer-free controls by age and gender. OUTCOME MEASURES: Measures of the three disgust traits were taken alongside measures of anxiety and depression. RESULTS: Disgust sensitivity and physical self-disgust were significantly higher in the cancer than control sample, while disgust propensity and behavioural self-disgust were lower. The disgust traits had a different pattern of associations to psychological wellbeing across the two groups, with disgust sensitivity predicting depressive symptoms to a significantly greater extent in the cancer than control group. CONCLUSIONS: People with cancer differ from matched controls in their disgust responses and these responses have significant predictive relationships with aspects of their psychological wellbeing. The results suggest that emotion-based interventions may be useful for improving psychological wellbeing in people with cancer.


Assuntos
Emoções , Neoplasias/psicologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Ansiedade/diagnóstico , Ansiedade/psicologia , Estudos de Casos e Controles , Estudos Transversais , Depressão/diagnóstico , Depressão/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Autoimagem , Adulto Jovem
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