An event-related potential study on the interaction between lighting level and stimulus spatial location

Due to heterogeneous photoreceptor distribution, spatial location of stimulation is crucial to study visual brain activity in different light environments. This unexplored issue was studied through occipital event-related potentials (ERPs) recorded from 40 participants in response to discrete visual stimuli presented at different locations and in two environmental light conditions, low mesopic (L, 0.03 lux) and high mesopic (H, 6.5 lux), characterized by a differential photoreceptor activity balance: rod > cone and rod < cone, respectively. Stimuli, which were exactly the same in L and H, consisted of squares presented at fixation, at the vertical periphery (above or below fixation) or at the horizontal periphery (left or right). Analyses showed that occipital ERPs presented important L vs. H differences in the 100 to 450 ms window, which were significantly modulated by spatial location of stimulation: differences were greater in response to peripheral stimuli than to stimuli presented at fixation. Moreover, in the former case, significance of L vs. H differences was even stronger in response to stimuli presented at the horizontal than at the vertical periphery. These low vs. high mesopic differences may be explained by photoreceptor activation and their retinal distribution, and confirm that ERPs discriminate between rod– and cone-originated visual processingThis work was supported by the grant PSI2014-54853-P and PSI2012-37090 from the Ministerio de Economía y Competitividad of Spain (MINECO

MATTER in emotion research: Spanish standardization of an affective image set

This is a pre-print of an article published in Behavior Research Methods. The final authenticated version is available online at: https://doi.org/10.3758/s13428-021-01567-9.Pictures with affective content have been widely used in the scientific study of emotions, from two main perspectives: on the one hand, dimensional theories claiming that affective experiences can be described according to a few fundamental dimensions such as valence and arousal, and on the other hand, discrete-category theories proposing the presence of a number of basic and universal emotions. Although it has been demonstrated that these two approaches are not mutually exclusive, the existing standardized affective picture databases have been created from the dimensional perspective, which has led to important gaps for research focused on discrete emotions. The present work introduces MATTER, a new database comprising 540 pictures depicting disgusting, fearful, neutral, erotic, mirthful and incongruent content, which provides normative values (total N = 368, mean = 120.47 ratings/picture) in valence and arousal dimensions, as well as in discrete affective (disgust, fear, erotica and mirth) and cognitive (incongruence and interest) features. A tentative classification into discrete categories is presented, and the physical properties of each picture are reported. Our findings suggest that MATTER constitutes a modern and suitable set of affective images including, for the first time, both mirth- and incongruence-related pictures. Additionally, it will enable the examination of affective and cognitive processes in fear/disgust and humor/incongruence fields

A New Look at Cardiac Defense: Attention or Emotion?

El estudio de la respuesta cardiaca de defensa tiene una larga tradición en la investigación psicológica, tanto desde la perspectiva cognitiva –vinculada a los trabajos de Pavlov, Sokolov y Graham sobre los reflejos sensoriales–, como desde la perspectiva motivacional –vinculada a los trabajos de Cannon e investigadores posteriores, sobre los conceptos de activación y estrés–. Estas dos perspectivas han sido difíciles de integrar en el pasado. El presente artículo resume una serie de estudios sobre la respuesta cardiaca de defensa, desde una perspectiva diferente, que permite integrar las dos aproximaciones tradicionales. La nueva perspectiva hace hincapié en una interpretación procesual y secuencial de la respuesta cardiaca de defensa. Los resultados de estudios descriptivos y paramétricos, junto con los de estudios que examinan los mecanismos fisiológicos y psicológicos subyacentes a la respuesta, ponen de manifiesto un patrón complejo de cambios cardiacos en los que aparecen componentes tanto acelerativos como desacelerativos, con influencias simpáticas y parasimpáticas, y con significación tanto atencional como emocional. Las implicaciones de esta nueva visión de la respuesta defensiva del corazón se discuten en relación con la defensa en contextos naturales, los mecanismos cerebrales que controlan tales reacciones y sus efectos sobre la salud y la enfermedad.The study of cardiac defense has a long tradition in psychological research both within the cognitive approach—linked to Pavlov, Sokolov, and Graham’s work on sensory reflexes—and within the motivational one—linked to the work of Cannon and subsequent researchers on the concepts of activation and stress. These two approaches have been difficult to reconcile in the past. We summarize a series of studies on cardiac defense from a different perspective, which allows integration of the traditional approaches. This new perspective emphasizes a sequential process interpretation of the cardiac defense response. Results of descriptive and parametric studies, as well as those of studies examining the physiological and psychological mechanisms underlying the response, show a complex response pattern with both accelerative and decelerative components, with both sympathetic and parasympathetic influences, and with both attentional and emotional significance. The implications of this new look at cardiac defense are discussed in relation to defensive reactions in natural settings, the brain mechanisms controlling such reactions, and their effects on health and illnes

Habituation and sensitization of protective reflexes: dissociation between cardiac defense and eye-blink startle

We examined the habituation and recovery of two protective reflexes, cardiac defense and eye-blink startle, simultaneously elicited by a white noise of 500 ms as a function of the time interval between stimulus presentations. Participants were 90 volunteers (54 women) randomly distributed into 6 inter-trial interval (ITI) conditions. They all received three presentations of the stimulus with a time interval of 30 min between the first and third noise. The timing of the second noise was manipulated in six steps, using a between-group design, in order to increase the ITI between Trials I and 2 and symmetrically decrease the ITI between Trials 2 and 3. Cardiac defense showed fast habituation at the shortest ITI (2.5 min), but reduced habituation and increased recovery at the longest ITI (27.5 min). In contrast, eye-blink startle showed sensitization irrespective of the ITI. This pattern of findings highlights dissociations between protective reflexes when simultaneously examined. The results are discussed in the context of the cascade model of defense reactions. (C) 2009 Elsevier B.V. All rights reserved

Ambient light modulation of exogenous attention to threat

Planet Earth’s motion yields a 50 % day–50 % night yearly balance in every latitude or longitude, so survival must be guaranteed in very different light conditions in many species, including human. Cone- and rod-dominant vision, respectively specialized in light and darkness, present several processing differences, which are—at least partially—reflected in event-related potentials (ERPs). The present experiment aimed at characterizing exogenous attention to threatening (spiders) and neutral (wheels) distractors in two environmental light conditions, low mesopic (L, 0.03 lx) and high mesopic (H, 6.5 lx), yielding a differential photoreceptor activity balance: rod &gt; cone and rod &lt; cone, respectively. These distractors were presented in the lower visual hemifield while the 40 participants were involved in a digit categorization task. Stimuli, both targets (digits) and distractors, were exactly the same in L and H. Both ERPs and behavioral performance in the task were recorded. Enhanced attentional capture by salient distractors was observed regardless of ambient light level. However, ERPs showed a differential pattern as a function of ambient light. Thus, significantly enhanced amplitude to salient distractors was observed in posterior P1 and early anterior P2 (P2a) only during the H context, in late P2a during the L context, and in occipital P3 during both H and L contexts. In other words, while exogenous attention to threat was equally efficient in light and darkness, cone-dominant exogenous attention was faster than rod-dominant, in line with previous data indicating slower processing times for rod- than for cone-dominant visionThis research was supported by the Grants PSI2014-54853-P and PSI2012-37090 from the Ministerio de Economía y Competitividad of Spain (MINECO

In exogenous attention, time is the clue: Brain and heart interactions to survive threatening stimuli.

The capture of exogenous attention by negative stimuli has been interpreted as adaptive for survival in a diverse and changing environment. In the present paper, we investigate the neural responses towards two discrete negative emotions with different biological meanings, disgust and fear, and its potential relationships with heart rate variability (HRV) as an index of emotional regulation. With that aim, 30 participants performed a digit categorization task while fear, disgust and neutral distractor pictures were presented. Resting HRV at baseline, behavioral responses, and event-related potentials were recorded. Whereas P1 amplitudes were highest to fear distractors, the disgust stimulation led to augmented P2 amplitudes compared to the rest of distractors. Interestingly, increased N2 amplitudes were also found to disgust distractors, but only in high HRV participants. Neural source estimation data point to the involvement of the insula in this exogenous attentional response to disgust. Additionally, disgust distractors provoked longer reaction times than fear and neutral distractors in the high HRV group. Present findings are interpreted in evolutionary terms suggesting that exogenous attention is captured by negative stimuli following a different time course for fear and disgust. Possible HRV influences on neural mechanisms underlying exogenous attention are discussed considering the potential important role of this variable in emotional regulation processes

Modulación no consciente de la respuesta cardiaca de defensa por imágenes fóbicas

El presente estudio examina el efecto de visualizar una imagen fóbica frente a una imagen no fóbica en la modulación de la respuesta cardiaca de defensa provocada por un estímulo auditivo intenso. 48 mujeres con miedo a las arañas fueron examinadas siguiendo un diseño factorial de dos grupos independientes (grupo de enmascaramiento hacia atrás no efectivo y grupo de enmascaramiento hacia atrás efectivo) y dos presentaciones del estímulo auditivo precedido de una imagen visual (una fóbica y otra no fóbica). La variable dependiente fue la frecuencia cardiaca segundo-a-segundo analizada durante los 80 segundos posteriores al estímulo auditivo. 6 sujetos del grupo de enmascaramiento efectivo fueron excluidos del análisis por haber reconocido alguno de los dos estímulos visuales. Los resultados del análisis con los sujetos restantes muestran el efecto esperado de la modulación emocional: la imagen fóbica, en comparación con la imagen no fóbica, potencia la respuesta cardiaca de defensa. Los mismos efectos se observan en los grupos consciente y no consciente. Se discuten los resultados en el contexto de las teorías del priming motivacional de Peter Lang y del procesamiento preatencional del miedo fóbico de Arne Öhman