► Phase-synchronization (PS) of gamma-band responses (GBRs) to novel sounds measured. ► Participants responded to neutral or appetitive pictures, ignoring novel sounds. ► Distractor sounds decreased ...hit rate in the appetitive context compared to neutral. ► Gamma-PS (35Hz) to novel sounds increased in appetitive context, but not in neutral. ► Gamma-PS is tuned under conditions that could promote long-term survival.
Based on the previous study where phase-synchronization (PS) of gamma-band responses (GBRs) proved a reliable cerebral correlate of involuntary attention and its enhancement under threat, we measured gamma-PS elicited by novel sounds from human electroencephalogram (EEG) scalp-recordings when participants responded to visual stimuli displaying either highly motivational or neutral sceneries. We then tested the modulatory effect of the emotional conditions on auditory responses. Novel distractor sounds did not affect behavioural accuracy on subjects’ visual task performance in neutral context but markedly decreased hit rate in the appetitive one. Similarly, gamma-PS to novel sounds remained intact in neutral context, whereas it showed an increase, within the 35-Hz sub-range, in the appetitive context. These results suggest that a context of processing positive emotional stimuli results into an enhanced processing of task-irrelevant novel auditory events, and, furthermore, that gamma-PS is tuned under conditions that could promote long-term survival.
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We used an auditory-visual distraction task to investigate the functional relationship between distraction elicited by auditory novel events and a context of negative emotional processing, both at ...behavioural and electrophysiological (event-related brain potentials) levels in humans. Participants performed a decision task on pictures disclosing sceneries with a task-irrelevant emotional load or neutral, whereas ignoring sounds presented concomitantly. Our data showed that novel sounds yielded stronger behavioural disruption on participants' visual task performance in negative context compared to the neutral one. Accordingly, late novelty P3 responses to novel sounds were enhanced. These results demonstrate that the negative emotional context enhances the activation of neural networks in the auditory novelty system, enhancing auditory novelty processing under potentially threatening conditions.
Abstract
The waking brain efficiently detects emotional signals to promote survival. However, emotion detection during sleep is poorly understood and may be influenced by individual sleep ...characteristics or neural reactivity. Notably, dream recall frequency has been associated with stimulus reactivity during sleep, with enhanced stimulus-driven responses in high vs. low recallers. Using electroencephalography (EEG), we characterized the neural responses of healthy individuals to emotional, neutral voices, and control stimuli, both during wakefulness and NREM sleep. Then, we tested how these responses varied with individual dream recall frequency. Event-related potentials (ERPs) differed for emotional vs. neutral voices, both in wakefulness and NREM. Likewise, EEG arousals (sleep perturbations) increased selectively after the emotional voices, indicating emotion reactivity. Interestingly, sleep ERP amplitude and arousals after emotional voices increased linearly with participants’ dream recall frequency. Similar correlations with dream recall were observed for beta and sigma responses, but not for theta. In contrast, dream recall correlations were absent for neutral or control stimuli. Our results reveal that brain reactivity to affective salience is preserved during NREM and is selectively associated to individual memory for dreams. Our findings also suggest that emotion-specific reactivity during sleep, and not generalized alertness, may contribute to the encoding/retrieval of dreams.
ENGLISH: SUMMARYThe present thesis encloses four studies that sought to asses the neural correlates, timing and modulatory effects of a negative emotional context on the processing of task-irrelevant ...novel sounds within the framework of auditory-visual oddball experimentation. Study I, II and III were conducted using event-related brain potentials (ERP) and Study IV used functional magnetic resonance imaging (fMRI).In Study I, fourteen healthy volunteers responded to a visual discrimination task, with either neutral or threatening sceneries, while a 64-channel electroencephalogram (EEG) was recorded. In Study II, fourteen healthy female volunteers responded to visual stimuli displaying either threatening or neutral sceneries, using an optimised version of the task, while a 64-channel electroencephalogram (EEG) was recorded. In Study III, fourteen female subjects and fourteen male subjects were recorded using a 64-channel electroencephalogram (EEG) while performing the same visual discrimination task as in Study II. In Study IV, seventeen healthy female volunteers responded to a visual colour discrimination task, with images of emotional facial expressions (angry, fearful or neutral), while neuroimaged in a 3Tesla scanner. In all experimental designs, single auditory stimuli, consisting of a majority of standard tones and infrequent novel environmental sounds, preceded the images and had to be ignored by the subjects. The main results in all four studies were pointing at comparable conclusions. Novel sounds elicited a distracting effect on subjects' performance, reflected by longer response times compared to those in standard trials. This effect was consistently magnified when preceding and following images were of a negative emotional load as compared to the neutral images. In Study III, women, but not men, showed this effect.Brain responses recorded with ERPs revealed, in Study I, an enhancement of late novelty-P3 responses to novel sounds in negative context, compared to the neutral one. Furthermore, Study II demonstrated that this modulatory effect can also occur in the early phase of this ERP component. Study III showed that the modulation of the early novelty-P3 was present only in women. Hemodynamic responses, in turn, showed that activation induced by novel sounds in superior temporal gyrus, comprising secondary cortex, planum temporale and primary auditory cortex, was enhanced when subjects responded to faces with a negative emotional expression compared to the neutral ones. The combination of results in the four studies show that the emotional context enhances excitability of auditory novelty cerebral regions at early stages of processing, making irrelevant sounds become more available in the attentional set under threatening conditions. Still, gender differences may be present in these effects, possibly due to differences in the evaluation of the emotional stimuli.
CATALÀ:La present tesi inclou quatre estudis que pretenen determinar els correlats neurals, temporalitat i efectes modulatoris d'un context emocional negatiu en el processament de sons novedosos irrellevants per la tasca en curs, en el marc de l'experimentació oddball auditivo- visual. L'Estudi I, II i III van ser duts a terme amb la tècnica de potencials evocats (PEs) i per l'Estudi IV es va utilitzar resonància magnètica funcional (RMf).A l'Estudi I, catorze voluntaris sans van respondre a una tasca de discriminació visual, amb escenes bé neutres, bé amenaçants, mentre s'enregistrava el seu electroencefalograma (EEG) de 64 canals. A l'Estudi II, catorze voluntàries sanes van respondre a estímuls visuals que representaven, bé escenes amenaçants o bé neutres, utilitzant una versió optimitzada de la tasca, mentre s'enregistrava el seu electroencefalograma (EEG) de 64 canals. A l'Estudi III, catorze dones i catorze homes van ser enregistrats utilitzant electroencefalograma (EEG) de 64 canals mentre realitzaven la mateixa tasca de discriminació visual que a l'Estudi II. A l'Estudi IV, disset voluntàries sanes van respondre a una tasca de discriminació de color, amb imatges d'expressions facials emocionals (d'amenaça, de por o neutra), mentre eren mesurades en un escàner de RMf de 3Tesla. En tots els dissenys experimentals, un estímul auditiu únic, que podia ser, bé en una majoria un to estàndard, o bé un so novedós ambiental infreqüent, precedia les imatges i havia d'ésser ignorat pels subjectes. Els principals resultats en tots quatre estudis apuntaren a conclusions comparables. Els sons novedosos produïren un efecte distractor en el rendiment dels subjectes, reflexat en temps de resposta més llargs comparats amb els assaigs amb sons estàndard. Aquest efecte va veure's consistentment magnificat quan les imatges precedents i següents tenien una càrrega emocional negativa en comparació a les imatges neutres. A l'Estudi III, les dones, però no els homes, van mostrar aquest efecte.Les respostes cerebrals enregistrades amb PEs revelaren, a l'Estudi I, un augment d'amplitud de la fase tardana del patró P3 de novetat davant de sons novedosos en context negatiu, en comparació amb el context neutre. A més, l'Estudi II va demostrar que aquest efecte modulatori pot ocórrer també en la fase primerenca d'aquest component de PE. L'Estudi III va mostrar que la modulació de la P3 de novetat era present només en dones. Les respostes hemodinàmiques, alhora, van mostrar que l'activació induïda pels sons novedosos al gir temporal superior, incloent escorça auditiva secundària, planum temporale i escorça auditiva primària, va ser augmentada quan els subjectes respongueren a cares amb una expressió emocional negativa en comparació amb les neutres. La combinació de resultats en els quatre estudis mostra que el context emocional augmenta l'excitabilitat de regions cerebrals en àrees primerenques de processament, fent que sons irrellevants es esdevinguin més disponibles en el set atencional en condicions d'amenaça. Tanmateix, és possible l'existència de diferències de gènere en aquests efectes, possiblement degut a diferències en l'avaluació dels estímuls emocionals. REFERENCESAlho, K., Winkler, I., Escera, C., Huotilainen, M., Virtanen, J., Jääskelainen, I.P., Pekkonen, E., Ilmoniemi, R.J. (1998). Processing of novel sounds and frequency changes in the human auditory cortex: magnetoencephalographic recordings. Psychophysiology, 35, 211-224.Bledowski, C., Prvulovic, D., Hoechstetter, K., Scherg, M., Wibral, M., Goebel, R., Linden, D.E.J. (2004). Localizing P300 generators in visual target and distractor processing: a combined event-related potential and functional magnetic resonance imaging study. The Journal of Neuroscience, 24(42), 9353-9360.Bradley, M.M., Codispoti, M., Lang, P.J. (2006). A multi-process account of startle modulation during affective perception. Psychophysiology, 43, 486-497.Clark, V.P., Fannon, S., Lai, S., Benson, R., Bauer, L. (2000). Responses to rare visual target and distractor stimuli using event-related fMRI. Journal of Neurophysiology, 83, 3133-3139. Cuthbert, B.N., Schupp, H.T., Bradley, M.M., McManis, M., Lang, P.J. (1998). Probing affective pictures: attended startle and tone probes. Psychophysiology, 35, 344-347.Escera, C., Alho, K., Winkler, I., Näätäänen, R. (1998). Neural mechanisms of involuntary attention to acoustic novelty and change. Journal of Cognitive Neuroscience, 10(5), 590-604.Escera, C., Alho, K., Schröger, E., Winkler, I. (2000). Involuntary attention and distractibility as evaluated with event-related brain potentials. Audiology and Neurootology, 5, 151-166.
Unspecific peroxygenases (UPOs) perform oxyfunctionalizations for a wide range of substrates utilizing H2O2 without the need for further reductive equivalents or electron transfer chains. Tailoring ...these promising enzymes toward industrial application was intensely pursued in the last decade with engineering campaigns addressing the heterologous expression, activity, stability, and improvements in chemo- and regioselectivity. One hitherto missing integral part was the targeted engineering of enantioselectivity for specific substrates with poor starting enantioselectivity. In this work, we present the engineering of the short-type MthUPO toward the enantiodivergent hydroxylation of the terpene model substrate, β-ionone. Guided by computational modeling, we designed a small smart library and screened it with a GC–MS setup. After two rounds of iterative protein evolution, the activity increased up to 17-fold and reached a regioselectivity of up to 99.6% for the 4-hydroxy-β-ionone. Enantiodivergent variants were identified with enantiomeric ratios of 96.6:3.4 (R) and 0.3:99.7 (S), respectively.
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IJS, KILJ, NUK, PNG, UL, UM
Las cavidades han sido lugares utilizados reiteradamente a lo largo de la historia y con distintas funcionalidades tal y como evidencia la tipología de los restos arqueológicos hallados. Así, la ...presencia de materiales arqueológicos en cuevas y abrigos desde la protohistoria hasta la actualidad está documentada en un buen número de yacimientos, pero pocos han sido objeto de estudio específico. La baja tasa de sedimentación y la escasez del registro pueden haber sido el principal factor de su poco interés, así como por el hecho que el estudio en cronologías históricas se ha centrado en la excavación de estructuras, ya sean poblados, ciudades, necrópolis, construcciones militares, entre otras. Las cavidades, como parte del territorio que las integran, deben tenerse en consideración en los estudios de reconstrucción histórica. En este caso, presentamos los niveles con materiales arqueológicos (cerámica, metales, industria ósea, monedas, carbones, vidrios y fauna) de cova del Gegant (Sitges, Barcelona) procedentes de tres momentos distintos: épocas ibérica, romana y ocupaciones modernas. A lo largo de la secuencia, la cueva ha tenido distintas funcionalidades, desde cobijo y espacio utilitario en época moderna y altoimperial a un posible uso relacionado con la ritualidad en época ibérica. De este momento destacan los objetos metálicos de carácter singular, especialmente de bronce, relacionados con ornamentos personales y posiblemente relacionados con rituales en un momento en que la cueva podría haber sido utilizada como cueva-santuario. Esta diversidad de funciones y su uso reiterado a lo largo de los dos últimos milenios indican la importancia de las cuevas como parte del hinterland territorial que forman parte en cada uno de los momentos históricos.
•Beat gestures help preschool children to recall contrastively focused words in discourse.•Beat gestures help preschool children to recall information related to contrastively focused words in ...discourse.•Beat gestures help preschool and first grade children to better comprehend a narrative discourse.
Although the positive effects of iconic gestures on word recall and comprehension by children have been clearly established, less is known about the benefits of beat gestures (rhythmic hand/arm movements produced together with prominent prosody). This study investigated (a) whether beat gestures combined with prosodic information help children recall contrastively focused words as well as information related to those words in a child-directed discourse (Experiment 1) and (b) whether the presence of beat gestures helps children comprehend a narrative discourse (Experiment 2). In Experiment 1, 51 4-year-olds were exposed to a total of three short stories with contrastive words presented in three conditions, namely with prominence in both speech and gesture, prominence in speech only, and nonprominent speech. Results of a recall task showed that (a) children remembered more words when exposed to prominence in both speech and gesture than in either of the other two conditions and that (b) children were more likely to remember information related to those words when the words were associated with beat gestures. In Experiment 2, 55 5- and 6-year-olds were presented with six narratives with target items either produced with prosodic prominence but no beat gestures or produced with both prosodic prominence and beat gestures. Results of a comprehension task demonstrated that stories told with beat gestures were comprehended better by children. Together, these results constitute evidence that beat gestures help preschoolers not only to recall discourse information but also to comprehend it.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
To study the differences in early-life characteristics between patients with an early onset of psychotic disorders (EOP, aged < 18 years) versus adult onset of psychotic disorders (AOP, aged ≥ 18 ...years) and to identify predictors of earlier onset.
278 patients with a first episode of psychosis between the ages of 7 and 35 years were recruited as part of a multicenter prospective longitudinal study conducted in Spain between January 1, 2009, and December 31, 2011, with diagnoses made for AOP using the Structured Clinical Interview for
Axis I Disorders (SCID-I) and for EOP using the Schedule for Affective Disorders and Schizophrenia for School-Aged Children (K-SADS). Early-stage factors such as prenatal, perinatal, and other premorbid factors were registered and compared between EOP and AOP patients. To analyze the association between baseline variables and outcome, univariate and multivariate logistic regression models were used, and the association or odds ratios (ORs) for significant risk factors were calculated.
224 patients with AOP (mean ± SD age = 25.6 ± 5.0 years; 65.6% male) and 54 patients with EOP (16.1 ± 1.7 years; 68.5% male) were included. Univariate analysis revealed significant differences between the groups. Specifically, compared to AOP subjects, EOP patients had more frequent obstetric complications (OCs) (
< .001), birth weight < 2.500 g (
< .028), a background of any personal psychiatric disorder (
< .001), a previous diagnosis of attention-deficit/hyperactivity disorder (
= .001), and premorbid IQ < 85 (
< .001). In the multivariate model, only OCs (OR = 5.44), personal psychiatric background (OR = 4.05), and IQ < 85 (OR = 3.96) predicted an onset of the first episode of psychosis before age 18 years.
Premorbid factors such as OCs, personal psychiatric background, and IQ < 85 could help predict which patients are more likely to have an early onset of psychosis. Awareness of these factors could help clinicians work to prevent the early transition to psychosis in children and adolescents.
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