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1.
Cogn Emot ; 37(5): 959-972, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37338015

RESUMO

Affective aspects of a stimulus can be processed rapidly and before cognitive attribution, acting much earlier for verbal stimuli than previously considered. Aimed for specific mechanisms, event-related brain potentials (ERPs), expressed in facial expressions or word meaning and evoked by six basic emotions - anger, disgust, fear, happy, sad, and surprise - relative to emotionally neutral stimuli were analysed in a sample of 116 participants. Brain responses in the occipital and left temporal regions elicited by the sadness in facial expressions or words were indistinguishable from responses evoked by neutral faces or words. Confirming previous findings, facial fear elicited an early and strong posterior negativity. Instead of expected parietal positivity, both the happy faces and words produced significantly more negative responses compared to neutral. Surprise in facial expressions and words elicited a strong early response in the left temporal cortex, which could be a signature of appraisal. The results of this study are consistent with the view that both types of affective stimuli, facial emotions and word meaning, set off rapid processing and responses occur very early in the processing stage.


Assuntos
Eletroencefalografia , Emoções , Humanos , Eletroencefalografia/métodos , Emoções/fisiologia , Potenciais Evocados/fisiologia , Encéfalo/fisiologia , Felicidade , Expressão Facial
2.
Appetite ; 168: 105758, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34655665

RESUMO

Momentary positive and negative emotions have shown to affect eating behaviour. In this study, we used experience sampling method (ESM) to assess how momentary positive affect (PA) and negative affect (NA) relate to overeating (OE) and binge eating (BE) episodes among men and women compared to no OE/BE episodes. We additionally looked at how situational and social context moderate these relationships. For this purpose, 87 women and 94 men participated in the study where they were instructed to rate their levels of various positive and negative emotions, situational whereabouts, and the presence of OE/BE 7 times a day for 3 consecutive days. We found that men and women greatly differed in how momentary PA and NA relate to OE and BE. In women, NA was highest before BE, followed by OE compared to no OE/BE. Further, an interaction between the type of an eating episode and situational context demonstrated that this relationship was significant when at home, but not away from home. No differences in the momentary NA between the types of eating episodes were found in men. In men, PA was significantly higher before OE compared to BE and no OE/BE. Additionally, an interaction between the type of eating episode and situational context showed that this relationship was significant when at home, but not when away from home. Our results further confirm the role of negative affect in overeating and binge eating in women, whereas also suggesting that the role of positive affect in eating behaviour is warranted more research, particularly in men.


Assuntos
Transtorno da Compulsão Alimentar , Bulimia , Afeto , Avaliação Momentânea Ecológica , Comportamento Alimentar , Feminino , Humanos , Hiperfagia , Masculino
3.
Conscious Cogn ; 93: 103150, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34051391

RESUMO

The present study investigates how the brain automatically discriminates emotional schematic faces, as indicated by the mismatch responses, and how reliable these brain responses are. Thirty-three healthy volunteers participated in the vMMN EEG experiment with four experimental sets differing from each other by the type of standard (object with scrambled face features) and the type of deviants (Angry, Happy and Neutral schematic faces) presented. Conscious subjective evaluations of valence, arousal and attention catching of the same stimuli showed clear differentiation of emotional expressions. Deviant faces elicited rather similar vMMN at frontal and occipital sites. Bayesian analyses suggest that vMMN does not differ between angry and happy faces. Neutral faces, however, did not yield statistically significant vMMN at occipital leads. Pearson's correlation and intra-class correlation analyses showed that the brain's reactions to the stimuli were highly stable within individuals across the experimental sets, whereas the mismatch responses were much more variable.


Assuntos
Eletroencefalografia , Expressão Facial , Teorema de Bayes , Encéfalo , Emoções , Humanos
4.
Appetite ; 133: 324-336, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30508611

RESUMO

Automatic detection of important and unexpected stimuli in the visual environment is crucial for survival. We sought to explore whether visual food stimuli are detected already in the pre-attentive stimulus processing phase, and whether hunger enhances such automatic detection. To attain these goals, we adapted an electroencephalography paradigm - visual mismatch negativity (vMMN). vMMN is a useful paradigm to study the processing of salient emotional stimuli which has not yet been applied in the context of eating behaviours. In our study, 18 right-handed women (25.2 ±â€¯7.4 years) underwent two experimental sessions: hunger and fed conditions. Participants had to focus on a 2-back working memory task in the center of the computer screen, while stimuli depicting high fat savoury (HFSA) and high fat sweet (HFSW) foods were presented as deviants in a stream of neutral standard stimuli in the four corners of the screen. Automatic detection of foods was observed within 80-360 ms after stimulus onset, although some foods were better detected than the others. In HFSA, hunger enhanced the processing of all deviant stimuli in the early (100-160 ms) and mid-latency (160-220 ms) time windows. As the modulating effect of hunger was not food-specific, hunger may enhance automatic detection of changes in the visual environment, regardless of the type of input. Nevertheless, hamburger in HFSA was better detected than other stimuli, indicated by larger peak amplitudes, which supports the food-specificity of hunger modulation. In HFSW, the modulating effect of hunger was not observed, possibly due to suboptimally chosen stimuli within this block. In conclusion, we believe that after careful stimulus selection vMMN has a great potential to be a reliable measure of early food-cue processing.


Assuntos
Fome , Percepção Visual , Adulto , Eletroencefalografia , Feminino , Alimentos , Humanos , Saciação , Adulto Jovem
6.
Acta Psychol (Amst) ; 244: 104195, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38412710

RESUMO

This study adopts a cross-linguistic perspective and investigates how musical expertise affects the perception of duration and pitch in language. Native speakers of Chinese (N = 44) and Estonian (N = 46), each group subdivided into musicians and non-musicians, participated in a mismatch negativity (MMN) experiment where they passively listened to both Chinese and Estonian stimuli, followed by a behavioral experiment where they attentively discriminated the stimuli in the non-native language (i.e., Chinese to Estonian participants and Estonian to Chinese participants). In both experiments, stimuli of duration change, pitch change, and duration plus pitch change were discriminated. We found higher behavioral sensitivity among Chinese musicians than non-musicians in perceiving the duration change in Estonian and higher behavioral sensitivity among Estonian musicians than non-musicians in perceiving all types of changes in Chinese, but no corresponding effect was found in the MMN results, which suggests a more salient effect of musical expertise on foreign language processing when attention is required. Secondly, Chinese musicians did not outperform non-musicians in attentively discriminating the pitch-related stimuli in Estonian, suggesting that musical expertise can be overridden by tonal language experience when perceiving foreign linguistic pitch, especially when an attentive discrimination task is administered. Thirdly, we found larger MMN among Chinese and Estonian musicians than their non-musician counterparts in perceiving the largest deviant (i.e., duration plus pitch) in their native language. Taken together, our results demonstrate a positive effect of musical expertise on language processing.


Assuntos
Música , Percepção da Altura Sonora , Humanos , Eletroencefalografia/métodos , Idioma , Linguística , Estimulação Acústica/métodos
7.
Neurosci Biobehav Rev ; 153: 105366, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37633625

RESUMO

Event-related potentials (ERPs), specifically the Mismatch Response (MMR), holds promise for investigating auditory maturation in children. It has the potential to predict language development and distinguish between language-impaired and typically developing groups. However, summarizing the MMR's developmental trajectory in typically developing children remains challenging despite numerous studies. This pioneering meta-analysis outlines changes in MMR amplitude among typically developing children, while offering methodological best-practices. Our search identified 51 articles for methodology analysis and 21 for meta-analysis, involving 0-8-year-old participants from 2000 to 2022. Risk of Bias assessment and methodology analysis revealed shortcomings in control condition usage and reporting of study confounders. The meta-analysis results were inconsistent, indicating large effect sizes in some conditions and no effect sizes in others. Subgroup analysis revealed the main effects of age and brain region, as well as an interaction of age and time-window of the MMR. Future research requires a specific protocol, larger samples, and replication studies to deepen the understanding of the auditory discrimination maturation process in children.

8.
Brain Behav ; 13(8): e3106, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37278143

RESUMO

OBJECTIVES: The Estonian National Mental Health Study (EMHS) was conducted in 2021-2022 to provide population-wide data on mental health in the context of COVID-19 pandemic. The main objective of this paper is to describe the rationale, design, and methods of the EMHS and to evaluate the survey response. METHODS: Regionally representative stratified random sample of 20,000 persons aged 15 years and older was drawn from the Estonian Population Register for the study. Persons aged 18 years and older at the time of the sampling were enrolled into three survey waves where they were invited to complete an online or postal questionnaire about mental well-being and disorders, and behavioral, cognitive, and other risk factors. Persons younger than 18 years of age were invited to fill an anonymous online questionnaire starting from wave 2. To complement and validate survey data, data on socio-demographic, health-related, and environmental variables were collected from six national administrative databases and registries. Additionally, a subsample was enrolled into a validation study using ecological momentary assessment. RESULTS: In total, 5636 adults participated in the survey wave 1, 3751 in wave 2, and 4744 in wave 3. Adjusted response rates were 30.6%, 21.1%, and 27.6%, respectively. Women and older age groups were more likely to respond. Throughout the three survey waves, a considerable share of adult respondents screened positive for depression (27.6%, 25.1%, and 25.6% in waves 1, 2, and 3, respectively). Women and young adults aged 18 to 29 years had the highest prevalence of depression symptoms. CONCLUSIONS: The registry-linked longitudinal EMHS dataset comprises a rich and trustworthy data source to allow in-depth analysis of mental health outcomes and their correlates among the Estonian population. The study serves as an evidence base for planning mental health policies and prevention measures for possible future crises.


Assuntos
COVID-19 , Saúde Mental , Adulto Jovem , Humanos , Feminino , Idoso , Adolescente , COVID-19/epidemiologia , Pandemias , Estônia/epidemiologia , Estudos Longitudinais , Sistema de Registros
9.
R Soc Open Sci ; 10(2): 191375, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36756055

RESUMO

The low reproducibility rate in social sciences has produced hesitation among researchers in accepting published findings at their face value. Despite the advent of initiatives to increase transparency in research reporting, the field is still lacking tools to verify the credibility of research reports. In the present paper, we describe methodologies that let researchers craft highly credible research and allow their peers to verify this credibility. We demonstrate the application of these methods in a multi-laboratory replication of Bem's Experiment 1 (Bem 2011 J. Pers. Soc. Psychol. 100, 407-425. (doi:10.1037/a0021524)) on extrasensory perception (ESP), which was co-designed by a consensus panel including both proponents and opponents of Bem's original hypothesis. In the study we applied direct data deposition in combination with born-open data and real-time research reports to extend transparency to protocol delivery and data collection. We also used piloting, checklists, laboratory logs and video-documented trial sessions to ascertain as-intended protocol delivery, and external research auditors to monitor research integrity. We found 49.89% successful guesses, while Bem reported 53.07% success rate, with the chance level being 50%. Thus, Bem's findings were not replicated in our study. In the paper, we discuss the implementation, feasibility and perceived usefulness of the credibility-enhancing methodologies used throughout the project.

11.
Brain ; 134(Pt 12): 3435-53, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21624926

RESUMO

Cognitive impairment is a core element shared by a large number of different neurological and neuropsychiatric diseases. Irrespective of their different aetiologies and symptomatologies, most appear to converge at the functional deficiency of the auditory-frontal cortex network of auditory discrimination, which indexes cognitive impairment shared by these abnormalities. This auditory-frontal cortical deficiency, and hence cognitive decline, can now be objectively measured with the mismatch negativity and its magnetic equivalent. The auditory-frontal cortical network involved seems, therefore, to play a pivotal, unifying role in the different abnormalities. It is, however, more likely that the dysfunction that can be detected with the mismatch negativity and its magnetoencephalographic equivalent manifests a more widespread brain disorder, namely, a deficient N-methyl-D-aspartate receptor function, shared by these abnormalities and accounting for most of the cognitive decline.


Assuntos
Envelhecimento/fisiologia , Córtex Auditivo/fisiopatologia , Lobo Frontal/fisiopatologia , Transtornos Mentais/fisiopatologia , Doenças do Sistema Nervoso/fisiopatologia , Percepção Auditiva/fisiologia , Transtornos Cognitivos/fisiopatologia , Potenciais Evocados Auditivos/fisiologia , Humanos
12.
Eur J Appl Physiol ; 112(12): 4091-101, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22487987

RESUMO

We examined the effect of heat acclimation (HA) on endurance capacity and blood prolactin (PRL) response to moderate intensity exercise in the heat in young male subjects (n = 21). Three exercise tests (ET) were completed on a treadmill: H1 (walk at 60% VO(2)peak until exhaustion at 42°C), N (walk at 22°C; duration equal to H1) and H2 (walk until exhaustion at 42°C after a 10-day HA program). Heart rate (HR), skin (T (sk)) and core (T (c)) temperatures and body heat storage (HS) were measured. Blood samples were taken immediately before, during and immediately after each ET. HA resulted in lower HR, T (sk), T (c) and HS rate (P < 0.05) during ET, whereas endurance capacity increased from 88.6 ± 27.5 min in H1 to 162.0 ± 47.8 min in H2 (P < 0.001). Blood PRL concentration was lower (P < 0.05) during exercise in H2 compared to H1 but the peak PRL level observed at the time of exhaustion did not differ in the two trials. Blood PRL concentration at 60 min of exercise in H1 correlated with time to exhaustion in H1 (r = -0.497, P = 0.020) and H2 (r = -0.528, P = 0.014). In conclusion, HA slows down the increase in blood PRL concentration but does not reduce the peak PRL level occurring at the end of exhausting endurance exercise in the heat. Blood PRL response to exercise in the heat in non-heat-acclimated subjects is associated with their endurance capacity in the heat in a heat-acclimated state.


Assuntos
Aclimatação/fisiologia , Exercício Físico/fisiologia , Temperatura Alta , Resistência Física/fisiologia , Prolactina/sangue , Adulto , Temperatura Corporal , Teste de Esforço , Frequência Cardíaca , Exaustão por Calor/fisiopatologia , Humanos , Masculino
13.
Scand J Psychol ; 53(3): 216-23, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22380709

RESUMO

A major problem in the research considering impulsivity is the lack of mutual understanding on how to measure and define impulsivity. Our study examined the relationship between self-reported impulsivity, behavioral excitatory and inhibitory processes and time perception. Impulsivity--fast, premature, thoughtless or disinhibited behavior--was assessed in 58 normal, healthy participants (30 men, mean age 21.9 years). Self-reported impulsivity as measured by Adaptive and Maladaptive Impulsivity Scale (AMIS) and behavioral excitatory and inhibitory processes as measured by Stop Signal Task were not directly related. Time perception, measured by the retrospective Time Estimation Task, was related to both. The length of the perceived time interval was positively correlated to AMIS Disinhibition subscale and negatively to several Stop Signal Task parameters. The longer subjects perceived the duration to last, the higher was their score on Disinhibition scale and the faster were their reactive responses in the Stop Signal Task. In summary our findings support the idea of cognitive tempo as a possible mechanism underlying impulsive behavior.


Assuntos
Comportamento Impulsivo/diagnóstico , Inibição Psicológica , Percepção do Tempo , Feminino , Humanos , Comportamento Impulsivo/psicologia , Masculino , Testes Neuropsicológicos , Tempo de Reação , Autorrelato , Inquéritos e Questionários , Adulto Jovem
14.
Front Hum Neurosci ; 15: 612617, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33994973

RESUMO

Similar to visual perception, auditory perception also has a clearly described "pop-out" effect, where an element with some extra feature is easier to detect among elements without an extra feature. This phenomenon is better known as auditory perceptual asymmetry. We investigated such asymmetry between shorter or longer duration, and level or falling of pitch of linguistic stimuli that carry a meaning in one language (Estonian), but not in another (Russian). For the mismatch negativity (MMN) experiment, we created four different types of stimuli by modifying the duration of the first vowel [ɑ] (170, 290 ms) and pitch contour (level vs. falling pitch) of the stimuli words ('SATA,' 'SAKI'). The stimuli were synthesized from Estonian words ('SATA,' 'SAKI') and follow the Estonian language three-way quantity system, which incorporates tonal features (falling pitch contour) together with temporal patterns. This made the meaning of the word dependent on the combination of both features and allows us to compare the relative contribution of duration and pitch contour in discrimination of language stimuli in the brain via MMN generation. The participants of the experiment were 12 Russian native speakers with little or no experience in Estonian and living in Estonia short-term, and 12 Estonian native speakers (age 18-27 years). We found that participants' perception of the linguistic stimuli differed not only according to the physical features but also according to their native language, confirming that the meaning of the word interferes with the early automatic processing of phonological features. The GAMM and ANOVA analysis of the reversed design results showed that the deviant with longer duration among shorter standards elicited a MMN response with greater amplitude than the short deviant among long standards, while changes in pitch contour (falling vs. level pitch) produced neither strong MMN nor asymmetry. Thus, we demonstrate the effect of language background on asymmetric perception of linguistic stimuli that aligns with those of previous studies (Jaramillo et al., 2000), and contributes to the growing body of knowledge supporting auditory perceptual asymmetry.

15.
Behav Brain Res ; 407: 113255, 2021 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-33745984

RESUMO

The exact mechanism how serotonergic and dopaminergic systems relate to one another in working memory (WM) updating is unknown. Platelet monoamine oxidase (MAO) has been used as a marker for central serotonergic capacity, and catechol-O-methyltransferase (COMT) as a marker for central dopaminergic capacity. This study aimed to describe the interaction of platelet MAO activity and COMT Val158Met genotype in visual working memory updating: the ability to replace old information with new within hundreds of milliseconds. Previous studies suggest that platelet MAO activity and COMT Val158Met genotype could have an interaction effect on working memory. However, there are no studies that have directly examined the interaction of these biomarkers in WM updating. We used a 2-back updating task with facial expressions and defined updating efficiency as response times for correct responses. 455 subjects from a population representative sample were included. Mixed models were used for data analysis with an aim to study the interaction of COMT Val158Met genotype (Val/Val, Val/Met and Met/Met) and the level of MAO activity (high vs low). Education, IQ, sex, simple reaction times, and overall updating accuracy were included as covariates. We found that the effect of COMT Val158Met on updating efficiency depends on the level of platelet MAO activity. Low MAO in contrast to high MAO was associated with an increase in updating efficiency in Val/Met but a decrease in Met/Met. The results are discussed in the context of serotonin and dopamine functions in brain regions related to WM. The findings support the view that serotonin modulates dopaminergic activation in updating and contribute to understanding the role of serotonin in PFC, top-down inhibitory signals, and its interactions with dopamine in WM processes.


Assuntos
Plaquetas/metabolismo , Catecol O-Metiltransferase/genética , Função Executiva/fisiologia , Reconhecimento Facial/fisiologia , Memória de Curto Prazo/fisiologia , Monoaminoxidase/metabolismo , Adulto , Feminino , Humanos , Estudos Longitudinais , Masculino , Adulto Jovem
16.
J Psychoactive Drugs ; 52(3): 255-263, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32299306

RESUMO

The study aims to describe ayahuasca users in Estonia and compare their mental health and quality of life to those of nonusers. Ceremonial practices, motivation for ayahuasca use, use-related experiences, and subjective consequences of use are described. We conducted a cross-sectional case-controlled study of thirty ayahuasca users and thirty nonusers matched by gender, age, and education. The participants completed questionnaires, standardized psychometric tests, and neuropsychiatric interviews. Ayahuasca use in Estonia occurred mainly in (neo)shamanic group ceremonies. The main motives for ayahuasca use were spiritual development, self-knowledge, and spiritual experiences. The users reported mostly positive subjective consequences of ayahuasca use for their health and life. However, some difficult experiences and adverse effects were reported. No abuse of ayahuasca or addiction to it was found. Screening test indicators of depression and anxiety were lower in the ayahuasca-using group. No deterioration of the mental health of ayahuasca users in comparison to nonusers was found. The participants perceive their use of ayahuasca as a spiritual practice with mostly favorable outcomes for their health and life. They also perceive ayahuasca use in Estonia as a reasonably safe and self-limiting form of spiritual practice.


Assuntos
Banisteriopsis , Comportamento Ritualístico , Saúde Mental , Qualidade de Vida , Adulto , Idoso , Estudos de Casos e Controles , Estudos Transversais , Estônia , Feminino , Alucinógenos , Humanos , Masculino , Pessoa de Meia-Idade , Psicometria , Autoimagem , Xamanismo , Inquéritos e Questionários , Tempo
17.
Acta Psychol (Amst) ; 209: 103117, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32603911

RESUMO

Individual differences in updating emotional facial expressions in working memory are not fully understood. Here we focused on the effects of high trait anxiety and high depressiveness in men and women on updating schematic emotional facial expressions (sad, angry, scheming, happy, neutral). A population representative sample of young adults was divided into four emotional disposition groups based on STAI-T and MADRS cut-offs: high anxiety (HA, n = 41), high depressiveness (HD, n = 31), high depressiveness & high anxiety (HAHD, n = 65) and control (CT, n = 155). Participants completed a 2-back task with schematic emotional faces, and valence/arousal ratings and verbal recognition tasks. A novel approach was used to separate encoding from retrieval. We found an interaction of emotional dispositions and emotional faces in updating accuracy. HD group made more errors than HA when encoding happy schematic faces. Other differences between emotional dispositions on updating measures were found but they were not specific to any emotional facial expression. Our findings suggest that there is a minor happy disadvantage in HD in contrast to HA which can be seen in lower accuracy for visual encoding of happy faces, but not in retrieval accuracy, the speed of updating, nor perception of emotional content in happy faces. These findings help to explain differences and similarities between high trait anxiety and high depressiveness in working memory and processing of facial expressions. The results are discussed in relation to prevalent theories of information processing in anxiety and depression.


Assuntos
Ansiedade , Emoções , Expressão Facial , Memória de Curto Prazo , Transtornos de Ansiedade , Feminino , Humanos , Masculino , Adulto Jovem
18.
Front Psychol ; 10: 883, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31133914

RESUMO

Food reward is an important concept for research in eating behaviors. Many food reward tasks have been developed and are in active use. However, little is known how much these tasks overlap. Here, we sought to compare three promising food reward tasks: (1) the Leeds Food Preference Questionnaire (LFPQ; a procedure combining explicit ratings of wanting and liking and an implicit wanting task based on forced choice), (2) a hand grip force task, and (3) an emotional attentional blink (EAB) task. Specifically, we assessed whether the tasks are sensitive to changes in hunger, correlate with each other, and correlate with trait binge eating and snack food calorie intake. Thirty-nine women aged 25.51 ± 5.99 years, with a BMI of 22.51 ± 3.58 kg/m2 completed the three tasks twice: after a 6-h fast and following a breakfast meal. In the fasted condition, participants were also given ad libitum access to snack foods to assess calorie intake. Prior to the two laboratory sessions, participants completed a trait binge eating questionnaire. Results revealed that the LFPQ's explicit wanting and explicit liking subscales, as well as grip force reflected higher food reward scores in the fasted condition. The three metrics also correlated positively with each other. Explicit wanting and liking correlated with snack food intake, while grip force did not. None of the tasks were related to trait binge eating. Reaction times in the forced choice procedure did not reflect changes in hunger, but the task was nevertheless able to differentiate between foods varying in taste and fat content. The EAB was not sensitive to the hunger manipulation; neither did the task correlate with binge eating or energy intake. Collectively, our findings suggest that the explicit wanting and liking scales and the grip force task measure the same construct, whereas EAB results may be obscured by a variety of potential confounding factors. Future research could include additional food reward tasks in comparisons, measure covariates that may moderate the variables' associations, and compare hunger-dependent changes in food reward in different subgroups.

19.
Appl Physiol Nutr Metab ; 43(1): 63-70, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28873320

RESUMO

The adaptogen Rhodiola rosea (RR) may mitigate stress responses and have beneficial effects on endurance capacity (EC) and mental performance. Heat acclimation (HA) improves EC in the heat, but the potential impact of RR on the HA process is unknown. Therefore, our intent was to determine if RR has a positive impact on HA. Twenty male subjects (age, 22.5 ± 3.0 years) completed 2 EC tests involving walking (6 km·h-1) until volitional exhaustion in a climate chamber (air temperature, 42 °C; relative humidity, 18%) before (H1) and after (H2) an 8-day HA period. One group (SHR; n = 10) ingested standardised extract SHR-5 of RR (a single daily dose of 432 mg), while a second group (PLC; n = 10) administered a placebo prior to each HA session. Efficacy of HA was evaluated on the basis of changes that occurred from H1 to H2 in the time to exhaustion (TTE), exercise heart rate (HR), core and skin temperatures (Tc, Tsk), stress hormones, ratings of perceived exertion (RPE) and fatigue (RPF), and thermal sensation (TS). HA significantly increased TTE (133.1 ± 44.1 min in H1; 233.4 ± 59.8 min in H2; p < 0.0001) and decreased (p < 0.0001) HR, Tc, Tsk, stress hormones as well as RPE, RPF, and TS. However, the magnitude of all these changes was similar (p > 0.05) in the SHR and PLC groups. These results suggest that the use of RR during HA has no beneficial performance, physiological, or perceptual effects in young healthy males.


Assuntos
Aclimatação , Resposta ao Choque Térmico/efeitos dos fármacos , Temperatura Alta , Resistência Física/efeitos dos fármacos , Extratos Vegetais/uso terapêutico , Rhodiola , Adulto , Regulação da Temperatura Corporal/efeitos dos fármacos , Método Duplo-Cego , Estônia , Teste de Esforço , Voluntários Saudáveis , Frequência Cardíaca , Humanos , Masculino , Processos Mentais/efeitos dos fármacos , Fadiga Muscular/efeitos dos fármacos , Fitoterapia , Extratos Vegetais/isolamento & purificação , Plantas Medicinais , Rhodiola/química , Temperatura Cutânea/efeitos dos fármacos , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
20.
Emotion ; 18(8): 1174-1188, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29504799

RESUMO

Affective states are known to distort time perception, but it remains unclear why and how they do so. To test whether appraisal processes involved in affect may play a role in temporal distortions, we investigated bisection behavior during experimental events with varying appraisal values along three dimensions: goal relevance (high vs. low), goal type (approach vs. avoid), and goal congruence (conducive vs. obstructive). Forty female participants performed an incentive-compatible gambling task attempting to accumulate wins and avoid losses of small amounts of chocolate. On each trial, a prechoice stimulus first announced whether a win, a loss, or no change was available. Participants then made a choice that ostensibly determined the outcome of the trial, which was communicated by a postchoice stimulus. Participants also made temporal bisection decisions indicating whether the presentation durations of pre- and postchoice stimuli (which varied between 200, 320, 440, 560, 680, and 800 ms) were closer to a previously learned short (200 ms) or long (800 ms) standard. We analyzed appraisal effects on psychometric bisection point, response speed, and drift diffusion parameter variance using custom regression contrasts. Subjective durations were found to be lengthened by high goal relevance, conducive goal congruence, and approach goal type. Analysis of diffusion parameters suggested that these results reflected appraisal-related shifts in duration perception rather than in subsequent decision-making. These findings encourage further research into the possibility that temporal distortions are among the cognitive changes triggered by appraisal processes during affective states. (PsycINFO Database Record (c) 2018 APA, all rights reserved).


Assuntos
Comportamento de Escolha/fisiologia , Emoções/fisiologia , Percepção do Tempo/fisiologia , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
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