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1.
R Soc Open Sci ; 9(11): 220923, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36425519

RESUMEN

Studies of food-related behaviours often involve measuring responses to pictorial stimuli of foods. Creating these can be burdensome, requiring a significant commitment of time, and with sharing of images for future research constrained by legal copyright restrictions. The Restrain Food Database is an open-source database of 626 images of foods that are categorized as those people could eat more or less of as part of a healthy diet. This paper describes the database and details how to navigate it using our purpose-built R Shiny tool and a pre-registered online validation of a sample of images. A total of 2150 participants provided appetitive ratings, perceptions of nutritional content and ratings of image quality for images from the database. We found support for differences between Food Category on appetitive ratings which were also moderated by state hunger ratings. Findings relating to individual differences in appetite ratings as well as differences between BMI weight categories are also reported. Our findings validate the food categorization in the Restrain Food Database and provide descriptive information for individual images within this investigation. This database should ease the burden of selecting and creating appropriate images for future studies.

2.
R Soc Open Sci ; 8(8): 210666, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34457346

RESUMEN

Inhibitory control training effects on behaviour (e.g. 'healthier' food choices) can be driven by changes in affective evaluations of trained stimuli, and theoretical models indicate that changes in action tendencies may be a complementary mechanism. In this preregistered study, we investigated the effects of food-specific go/no-go training on action tendencies, liking and impulsive choices in healthy participants. In the training task, energy-dense foods were assigned to one of three conditions: 100% inhibition (no-go), 0% inhibition (go) or 50% inhibition (control). Automatic action tendencies and liking were measured pre- and post-training for each condition. We found that training did not lead to changes in approach bias towards trained foods (go and no-go relative to control), but we warrant caution in interpreting this finding as there are important limitations to consider for the employed approach-avoidance task. There was only anecdotal evidence for an effect on food liking, but there was evidence for contingency learning during training, and participants were on average less likely to choose a no-go food compared to a control food after training. We discuss these findings from both a methodological and theoretical standpoint and propose that the mechanisms of action behind training effects be investigated further.

3.
Appetite ; 167: 105601, 2021 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-34284065

RESUMEN

Inhibitory control training has recently been used as an intervention to aid healthy eating and encourage weight loss. The aim of this pre-registered study was to explore the effects of training on food liking, food consumption and weight loss in a large (n = 366), predominantly healthy-weight sample. Participants received four training sessions within a week, in which they had to inhibit their responses to either energy-dense foods (active group) or non-food images (control group). Subjective food ratings, food consumption frequency and weight were measured pre- and post-training. At two-weeks post-training, the active group reported a greater reduction in liking for energy-dense foods, compared to the control group. Active participants also reported a significantly greater increase in healthy food liking, immediately post-training, relative to the control group. There was no statistically significant difference between groups for the change in consumption of trained foods or for weight loss. These findings are partially consistent with previous research conducted in smaller, more overweight samples. Exploratory analyses suggest that some effects of training may be driven by awareness effects. Methodological differences across findings and avenues for future investigation are discussed.


Asunto(s)
Preferencias Alimentarias , Bocadillos , Adulto , Dieta Saludable , Humanos , Sobrepeso/prevención & control , Pérdida de Peso
4.
Behav Neurosci ; 134(5): 369-383, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33001679

RESUMEN

This study investigated whether the application of high definition transcranial DC stimulation (HD-tDCS) to the dorsolateral prefrontal cortex reduces cue-induced food craving when combined with food-specific inhibitory control training. Using a within-subjects design, participants (N = 55) received both active and sham HD-tDCS across 2 sessions while completing a Go/No-Go task in which foods were either associated with response inhibition or response execution. Food craving was measured pre and post stimulation using a standardized questionnaire as well as desire to eat ratings for foods associated with both response inhibition and response execution in the training task. Results revealed no effect of HD-tDCS on reducing state food craving or desire to eat. Due to the COVID-19 pandemic, we were unable to achieve our maximum preplanned sample size or our minimum desired Bayesian evidence strength across all a priori hypotheses; however 6 of the 7 hypotheses converged with moderate or stronger evidence in favor of the null hypothesis over the alternative hypothesis. We discuss the importance of individual differences and provide recommendations for future studies with an emphasis on the importance of cognitive interventions. (PsycInfo Database Record (c) 2020 APA, all rights reserved).


Asunto(s)
Ansia/fisiología , Preferencias Alimentarias/fisiología , Corteza Prefrontal/fisiología , Adulto , Teorema de Bayes , Estudios Cruzados , Señales (Psicología) , Femenino , Alimentos , Humanos , Masculino , Encuestas y Cuestionarios , Estimulación Transcraneal de Corriente Directa/métodos
5.
Wellcome Open Res ; 5: 6, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32500096

RESUMEN

Background: Exaggerations in health news were previously found to strongly associate with similar exaggerations in press releases. Moreover such exaggerations did not appear to attract more news. Here we assess whether press release practice changed after these reported findings; simply drawing attention to the issue may be insufficient for practical change, given the challenges of media environments. Methods: We assessed whether rates of causal over-statement in press releases based on correlational data were lower following a widely publicised paper on the topic, compared to an equivalent baseline period in the preceding year. Results: We found that over-statements in press releases were 28% (95% confidence interval = 16% to 45%) in 2014 and 13% (95% confidence interval = 6% to 25%) in 2015. A corresponding numerical reduction in exaggerations in news was not significant. The association between over-statements in news and press releases remained strong. Conclusions: Press release over-statements were less frequent following publication of Sumner et al. (2014). However, this is correlational evidence and the reduction may be due to other factors or natural fluctuations.

6.
Wellcome Open Res ; 4: 148, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31728413

RESUMEN

Background: Exaggerations in health news were previously found to strongly associate with similar exaggerations in press releases. Moreover, such press release exaggerations did not appear to attract more news. Methods: Here we tested the replicability of these findings in a new cohort of news and press releases based on research in UK universities in 2014 and 2015. Press releases and news were compared to their associated peer-reviewed articles to define exaggeration in advice, causal claims and human inference from non-human studies. Results: We found that the association between news and press releases did not replicate for advice exaggeration, while this association did replicate for causal claims and human inference from non-human studies. There was no evidence for higher news uptake for exaggerated press releases, consistent with previous results. Base exaggeration rates were lower for human inference from non-human studies, possibly reflecting the Concordat on Openness on Animal Research in the UK. Conclusions: Overall, the picture remains that the strength of news statements is normally associated with the strength of press release statements, and without evidence that exaggerated statements get significantly more news.

7.
Nutrients ; 11(9)2019 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-31487791

RESUMEN

With the obesity epidemic being largely attributed to overeating, much research has been aimed at understanding the psychological causes of overeating and using this knowledge to develop targeted interventions. Here, we review this literature under a model of food addiction and present evidence according to the fifth edition of the Diagnostic and Statistical Manual (DSM-5) criteria for substance use disorders. We review several innovative treatments related to a food addiction model ranging from cognitive intervention tasks to neuromodulation techniques. We conclude that there is evidence to suggest that, for some individuals, food can induce addictive-type behaviours similar to those seen with other addictive substances. However, with several DSM-5 criteria having limited application to overeating, the term 'food addiction' is likely to apply only in a minority of cases. Nevertheless, research investigating the underlying psychological causes of overeating within the context of food addiction has led to some novel and potentially effective interventions. Understanding the similarities and differences between the addictive characteristics of food and illicit substances should prove fruitful in further developing these interventions.


Asunto(s)
Adicción a la Comida/diagnóstico , Adicción a la Comida/terapia , Hiperfagia/diagnóstico , Hiperfagia/terapia , Humanos
8.
R Soc Open Sci ; 6(6): 190174, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31312488

RESUMEN

Despite being used interchangeably, different measures of restrained eating have been associated with different dietary behaviours. These differences have impeded replicability across the restraint literature and have made it difficult for researchers to interpret results and use the most appropriate measure for their research. Across a total sample of 1731 participants, this study compared the Restraint Scale (RS), and its subscales, to the Dutch Eating Behaviour Questionnaire (DEBQ) across several traits related to overeating. The aim was to explore potential differences between these two questionnaires so that we could help to identify the most suitable measure as a prescreening tool for eating-related interventions. Results revealed that although the two measures are highly correlated with one another (rs = 0.73-0.79), the RS was more strongly associated with external (rs = -0.07 to 0.11 versus -0.18 to -0.01) and disinhibited eating (rs = 0.46 versus 0.31), food craving (rs = 0.12-0.27 versus 0.02-0.13 and 0.22 versus -0.06) and body mass index (rs = 0.25-0.34 versus -0.13 to 0.15). The results suggest that, compared to the DEBQ, the RS is a more appropriate measure for identifying individuals who struggle the most to control their food intake.

9.
Wellcome Open Res ; 4: 56, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31346551

RESUMEN

Background This research is an investigation into the role of expert quotes in health news, specifically whether news articles containing a quote from an independent expert are less often exaggerated than articles without such a quote. Methods Retrospective quantitative content analysis of journal articles, press releases, and associated news articles was performed. The investigated sample are press releases on peer-reviewed health research and the associated research articles and news stories. Our sample consisted of 462 press releases and 668 news articles from the UK (2011) and 129 press releases and 185 news articles from The Netherlands (2015). We hand-coded all journal articles, press releases and news articles for correlational claims, using a well-tested codebook. The main outcome measures are types of sources that were quoted and exaggeration of correlational claims. We used counts, 2x2 tables and odds ratios to assess the relationship between presence of quotes and exaggeration of the causal claim. Results Overall, 99.1% of the UK press releases and 84.5% of the Dutch press releases contain at least one quote. For the associated news articles these percentages are: 88.6% in the UK and 69.7% in the Netherlands. Authors of the study are most often quoted and only 7.5% of UK and 7.0% of Dutch news articles contained a new quote by an expert source, i.e. one not provided by the press release. The relative odds that an article without an external expert quote contains an exaggeration of causality is 2.6. Conclusions The number of articles containing a quote from an independent expert is low, but articles that cite an external expert do contain less exaggeration.

10.
J Exp Psychol Appl ; 25(4): 517-542, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31246056

RESUMEN

Science stories in the media are strongly linked to changes in health-related behavior. Science writers (including journalists, press officers, and researchers) must therefore frame their stories to communicate scientific caution without disrupting coherence and disengaging the reader. In this study we investigate whether caveats ("Further research is needed to validate the results") satisfy this dual requirement. In four experiments participants read news reports with and without caveats. In Experiments 1 to 3, participants judged how cautious or confident researchers were, and how interesting or comprehensible they found the reports. News reports with caveats were judged as more cautious that those without, but levels of reader interest and comprehensibility were unaffected. In a fourth experiment, we created a mock newsroom and recruited journalism students to make judgments about which press releases should be published. Here, neither caveats nor the introduction of qualifying expressions in headlines had an effect on judgments of newsworthiness, consistent with Experiments 1 to 3. The reasons participants gave for rejecting a press release rarely referred to the caveat. Our results therefore suggest that science writers should include caveats in news reporting and that they can do so without fear of disengaging their readers or losing news uptake. (PsycINFO Database Record (c) 2019 APA, all rights reserved).


Asunto(s)
Comprensión , Difusión de la Información , Medios de Comunicación de Masas , Periódicos como Asunto , Ciencia , Humanos , Adulto Joven
11.
BMC Med ; 17(1): 91, 2019 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-31092248

RESUMEN

BACKGROUND: Misleading news claims can be detrimental to public health. We aimed to improve the alignment between causal claims and evidence, without losing news interest (counter to assumptions that news is not interested in communicating caution). METHODS: We tested two interventions in press releases, which are the main sources for science and health news: (a) aligning the headlines and main causal claims with the underlying evidence (strong for experimental, cautious for correlational) and (b) inserting explicit statements/caveats about inferring causality. The 'participants' were press releases on health-related topics (N = 312; control = 89, claim alignment = 64, causality statement = 79, both = 80) from nine press offices (journals, universities, funders). Outcomes were news content (headlines, causal claims, caveats) in English-language international and national media (newspapers, websites, broadcast; N = 2257), news uptake (% press releases gaining news coverage) and feasibility (% press releases implementing cautious statements). RESULTS: News headlines showed better alignment to evidence when press releases were aligned (intention-to-treat analysis (ITT) 56% vs 52%, OR = 1.2 to 1.9; as-treated analysis (AT) 60% vs 32%, OR = 1.3 to 4.4). News claims also followed press releases, significant only for AT (ITT 62% vs 60%, OR = 0.7 to 1.6; AT, 67% vs 39%, OR = 1.4 to 5.7). The same was true for causality statements/caveats (ITT 15% vs 10%, OR = 0.9 to 2.6; AT 20% vs 0%, OR 16 to 156). There was no evidence of lost news uptake for press releases with aligned headlines and claims (ITT 55% vs 55%, OR = 0.7 to 1.3, AT 58% vs 60%, OR = 0.7 to 1.7), or causality statements/caveats (ITT 53% vs 56%, OR = 0.8 to 1.0, AT 66% vs 52%, OR = 1.3 to 2.7). Feasibility was demonstrated by a spontaneous increase in cautious headlines, claims and caveats in press releases compared to the pre-trial period (OR = 1.01 to 2.6, 1.3 to 3.4, 1.1 to 26, respectively). CONCLUSIONS: News claims-even headlines-can become better aligned with evidence. Cautious claims and explicit caveats about correlational findings may penetrate into news without harming news interest. Findings from AT analysis are correlational and may not imply cause, although here the linking mechanism between press releases and news is known. ITT analysis was insensitive due to spontaneous adoption of interventions across conditions. TRIAL REGISTRATION: ISRCTN10492618 (20 August 2015).


Asunto(s)
Investigación Biomédica , Causalidad , Difusión de la Información , Medios de Comunicación de Masas , Investigación Biomédica/educación , Investigación Biomédica/normas , Comunicación , Método Doble Ciego , Medicina Basada en la Evidencia/normas , Conductas Relacionadas con la Salud , Promoción de la Salud/métodos , Promoción de la Salud/normas , Humanos , Difusión de la Información/métodos , Medios de Comunicación de Masas/normas , Salud Pública/normas , Salud Pública/estadística & datos numéricos , Reino Unido/epidemiología
12.
R Soc Open Sci ; 6(1): 181186, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30800367

RESUMEN

Modulation of dorsolateral prefrontal cortex (DLPFC) activity using non-invasive brain stimulation has been shown to reduce food craving as well as food consumption. Using a preregistered design, we examined whether bilateral transcranial direct current stimulation (tDCS) of the DLPFC could reduce food craving and consumption in healthy participants when administered alongside the cognitive target of inhibitory control training. Participants (N = 172) received either active or sham tDCS (2 mA; anode F4, cathode F3) while completing a food-related Go/No-Go task. State food craving, ad-lib food consumption and response inhibition were evaluated. Compared with sham stimulation, we found no evidence for an effect of active tDCS on any of these outcome measures in a predominantly female sample. Our findings raise doubts about the effectiveness of single-session tDCS on food craving and consumption. Consideration of individual differences, improvements in tDCS protocols and multi-session testing are discussed.

13.
Appetite ; 109: 11-23, 2017 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-27838443

RESUMEN

Training individuals to inhibit their responses towards unhealthy foods has been shown to reduce food intake relative to a control group. Here we aimed to further explore these effects by investigating the role of stimulus devaluation, training protocol, and choice of control group. Restrained eaters received either inhibition or control training using a modified version of either the stop-signal or go/no-go task. Following training we measured implicit attitudes towards food (Study 1) and food consumption (Studies 1 and 2). In Study 1 we used a modified stop-signal training task with increased demands on top-down control (using a tracking procedure and feedback to maintain competition between the stop and go processes). With this task, we found no evidence for an effect of training on implicit attitudes or food consumption, with Bayesian inferential analyses revealing substantial evidence for the null hypothesis. In Study 2 we removed the feedback in the stop-signal training to increase the rate of successful inhibition and revealed a significant effect of both stop-signal and go/no-go training on food intake (compared to double-response and go training, respectively) with a greater difference in consumption in the go/no-go task, compared with the stop-signal task. However, results from an additional passive control group suggest that training effects could be partly caused by increased consumption in the go control group whereas evidence for reduced consumption in the inhibition groups was inconclusive. Our findings therefore support evidence that inhibition training tasks with higher rates of inhibition accuracy are more effective, but prompt caution for interpreting the efficacy of laboratory-based inhibition training as an intervention for behaviour change.


Asunto(s)
Conducta de Elección , Condicionamiento Clásico , Ingestión de Alimentos/psicología , Conducta Alimentaria/psicología , Inhibición Psicológica , Adolescente , Adulto , Teorema de Bayes , Señales (Psicología) , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
14.
J Exp Psychol Appl ; 23(1): 1-14, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-27808530

RESUMEN

[Correction Notice: An Erratum for this article was reported in Vol 23(1) of Journal of Experimental Psychology: Applied (see record 2016-59631-001). In the article, the fourth author was inadvertently omitted from the advance online version. Also, the second paragraph of the author note should have included the following: "Amy Barrington contributed to the design and data collection for Experiments 2 and 3. We thank the following undergraduate students for contributions to Experiment 1 and pilot work leading up to the project: Laura Benjamin, Cecily Donnelly, Cameron Dunlop, Rebecca Emerson, Rose Fisher, Laura Jones, Olivia Manship, Hannah McCarthy, Naomi Scott, Eliza Walwyn-Jones, Leanne Whelan, and Joe Wilton." All versions of this article have been corrected.] Science-related news stories can have a profound impact on how the public make decisions. The current study presents 4 experiments that examine how participants understand scientific expressions used in news headlines. The expressions concerned causal and correlational relationships between variables (e.g., "being breast fed makes children behave better"). Participants rated or ranked headlines according to the extent that one variable caused the other. Our results suggest that participants differentiate between 3 distinct categories of relationship: direct cause statements (e.g., "makes," "increases"), which were interpreted as the most causal; can cause statements (e.g., "can make," "can increase"); and moderate cause statements (e.g., "might cause," "linked," "associated with"), but do not consistently distinguish within the last group despite the logical distinction between cause and association. On the basis of this evidence, we make recommendations for appropriately communicating cause and effect in news headlines. (PsycINFO Database Record


Asunto(s)
Comunicación , Comprensión/fisiología , Medios de Comunicación de Masas , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
15.
Appetite ; 95: 17-28, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26122756

RESUMEN

The majority of adults in the UK and US are overweight or obese due to multiple factors including excess energy intake. Training people to inhibit simple motor responses (key presses) to high-energy density food pictures reduces intake in laboratory studies. We examined whether online response inhibition training reduced real-world food consumption and weight in a community sample of adults who were predominantly overweight or obese (N = 83). Participants were allocated in a randomised, double-blind design to receive four 10-min sessions of either active or control go/no-go training in which either high-energy density snack foods (active) or non-food stimuli (control) were associated with no-go signals. Participants' weight, energy intake (calculated from 24-h food diaries), daily snacking frequency and subjective food evaluations were measured for one week pre- and post-intervention. Participants also provided self-reported weight and monthly snacking frequency at pre-intervention screening, and one month and six months after completing the study. Participants in the active relative to control condition showed significant weight loss, reductions in daily energy intake and a reduction in rated liking of high-energy density (no-go) foods from the pre-to post-intervention week. There were no changes in self-reported daily snacking frequency. At longer-term follow-up, the active group showed significant reductions in self-reported weight at six months, whilst both groups reported significantly less snacking at one- and six-months. Excellent rates of adherence (97%) and positive feedback about the training suggest that this intervention is acceptable and has the potential to improve public health by reducing energy intake and overweight.


Asunto(s)
Terapia Conductista/métodos , Conducta Alimentaria/psicología , Inhibición Psicológica , Obesidad/psicología , Sobrepeso/psicología , Adulto , Anciano , Registros de Dieta , Método Doble Ciego , Ingestión de Energía , Femenino , Preferencias Alimentarias/psicología , Humanos , Masculino , Persona de Mediana Edad , Obesidad/dietoterapia , Sobrepeso/dietoterapia , Bocadillos/psicología , Pérdida de Peso , Adulto Joven
16.
Appetite ; 85: 91-103, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25447023

RESUMEN

Overeating in our food-rich environment is a key contributor to obesity. Computerised response-inhibition training could improve self-control in individuals who overeat. Evidence suggests that training people to inhibit motor responses to specific food pictures can reduce the subsequent choice and consumption of those foods. Here we undertook three experiments using the stop-signal task to examine the effects of food and non-food related stop-training on immediate snack food consumption. The experiments examined whether training effects were stimulus-specific, whether they were influenced by the comparator (control) group, and whether they were moderated by individual differences in dietary restraint. Experiment 1 revealed lower intake of one food following stop- vs. double- (two key-presses) response training to food pictures. Experiment 2 offered two foods, one of which was not associated with stopping, to enable within- and between-subjects comparisons of intake. A second control condition required participants to ignore signals and respond with one key-press to all pictures. There was no overall effect of training on intake in Experiment 2, but there was a marginally significant moderation by dietary restraint: Restrained eaters ate significantly less signal-food following stop- relative to double-response training. Experiment 3 revealed that stop- vs. double-response training to non-food pictures had no effect on food intake. Taken together with previous findings, these results suggest some stimulus-specific effects of stop-training on food intake that may be moderated by individual differences in dietary restraint.


Asunto(s)
Ingestión de Energía , Conducta Alimentaria/psicología , Hiperfagia/prevención & control , Inhibición Psicológica , Adolescente , Adulto , Índice de Masa Corporal , Femenino , Humanos , Individualidad , Masculino , Persona de Mediana Edad , Bocadillos , Adulto Joven
17.
PLoS One ; 8(7): e70155, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23922948

RESUMEN

A recent study has shown that short-term training in response inhibition can make people more cautious for up to two hours when making decisions. However, the longevity of such training effects is unclear. In this study we tested whether training in the stop-signal paradigm reduces risky gambling when the training and gambling task are separated by 24 hours. Two independent experiments revealed that the aftereffects of stop-signal training are negligible after 24 hours. This was supported by Bayes factors that provided strong support for the null hypothesis. These findings indicate the need to better optimise the parameters of inhibition training to achieve clinical efficacy, potentially by strengthening automatic associations between specific stimuli and stopping.


Asunto(s)
Juego de Azar/psicología , Inhibición Psicológica , Adulto , Teorema de Bayes , Toma de Decisiones , Femenino , Juego de Azar/terapia , Humanos , Masculino , Adulto Joven
18.
J Neurophysiol ; 109(2): 437-44, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23114213

RESUMEN

Safe and effective transcranial magnetic stimulation (TMS) requires accurate intensity calibration. Output is typically calibrated to individual motor cortex excitability and applied to nonmotor brain areas, assuming that it captures a site nonspecific factor of excitability. We tested this assumption by correlating the effect of TMS at motor and visual cortex. In 30 participants, we measured motor threshold (MT) and phosphene threshold (PT) at the scalp surface and at coil-scalp distances of 3.17, 5.63, and 9.03 mm. We also modeled the effect of TMS in a simple head model to test the effect of distance. Four independent tests confirmed a significant correlation between PT and MT. We also found similar effects of distance in motor and visual areas, which did not correlate across participants. Computational modeling suggests that the relationship between the effect of distance and the induced electric field is effectively linear within the range of distances that have been explored empirically. We conclude that MT-guided calibration is valid for nonmotor brain areas if coil-cortex distance is taken into account. For standard figure-of-eight TMS coils connected to biphasic stimulators, the effect of cortical distance should be adjusted using a general correction factor of 2.7% stimulator output per millimeter.


Asunto(s)
Corteza Motora/fisiología , Estimulación Magnética Transcraneal/métodos , Corteza Visual/fisiología , Adulto , Calibración , Campos Electromagnéticos , Femenino , Humanos , Masculino , Modelos Neurológicos , Fosfenos , Desempeño Psicomotor , Umbral Sensorial , Percepción Visual
19.
Clin Neurophysiol ; 124(3): 536-44, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22986284

RESUMEN

OBJECTIVES: Past research has largely neglected to investigate mild adverse effects (MAEs) to transcranial magnetic stimulation (TMS), including headache and nausea. Here we explored the relationship between MAEs, participant characteristics (age and gender) and protocol parameters, including mode of application, coil geometry, stimulated brain region, TMS frequency, TMS intensity, and active vs. sham stimulation. METHODS: Data from 1270 standard post-monitoring forms was obtained from 113 healthy participants. Analyses aimed to identify the risk factors associated with MAE reports and specific symptoms. RESULTS: The overall rate of MAEs across TMS sessions was ∼5%, with ∼78% of symptoms occurring post-session. Initial TMS sessions were followed by a higher MAE incidence rate relative to later testing sessions. No associations between participant characteristics, TMS frequency, or intensity were observed. CONCLUSIONS: TMS-related MAEs are relatively common and may be exacerbated by initial expectations or anxieties of participants. A significant proportion of MAEs may reflect reporting of coincidental phenomena that are unrelated to TMS. Recommendations for future safety studies are proposed and monitoring documentation is provided. SIGNIFICANCE: Our findings illustrate the importance of standardized monitoring of MAEs. Such research aids our understanding of how MAEs arise and may lead to interventions for reducing their incidence.


Asunto(s)
Encéfalo/fisiología , Cefalea/epidemiología , Náusea/epidemiología , Estimulación Magnética Transcraneal/efectos adversos , Adolescente , Adulto , Femenino , Cefalea/etiología , Humanos , Incidencia , Masculino , Náusea/etiología
20.
Acta Psychol (Amst) ; 139(3): 515-23, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22366727

RESUMEN

Goal-directed attention prioritises perception of task-relevant stimuli according to location, features, or onset time. In this study we compared the behavioural timecourse of goal-directed selection to locations and colours by varying the stimulus-onset asynchrony (SOA) between cue and target in a strategic cueing paradigm. Participants reported the presence or absence of a target following prior information regarding its location or colour. Results revealed that preparatory selection by colour is more effective at enhancing perceptual sensitivity than selection by location, even though both types of cue provided equivalent overall information. More detailed analysis revealed that this advantage arose due a limitation of spatial attention in maintaining a sufficiently broad focus (>2°) for target detection across multiple stimuli. In contrast, when target stimuli fell within 2° of the spatial attention spotlight, the strategic advantages and speed of spatial and colour attention were equated. Our findings are consistent with the conclusion that, under spatially optimal conditions, prior spatial and colour information are equally proficient at guiding top-down selection. When spatial locations are ambiguous, however, colour-based selection is the more efficient mechanism.


Asunto(s)
Atención/fisiología , Percepción Espacial/fisiología , Percepción Visual/fisiología , Adulto , Color , Señales (Psicología) , Femenino , Objetivos , Humanos , Masculino , Tiempo de Reacción , Factores de Tiempo
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