Psychophysiological studies of unattended information processing

[Abstract] The article describes the general methods and some of the results obtained in the Psychophysiology Laboratory of the University of La Coruña. The paper covers our research on the Simon effect and accessory effect, although it is not a review of the literature. The research strategy we followed is built around the use of lateralized motor potentials recorded from scalp. These measures allow observing the way responses are selected and when they are selected, providing an invaluable tool to study response interference and to split reaction time into two halves. The research on the Simon effect concludes that interference during response selection is critical in the Simon effect but it is dubious whether this process should be considered as automatic and stimulus-driven, as is widely accepted. The experiments with the accessory effect indicate that facilitation is produced before response selection is over, which ends a long controversy about the locus of the accessory effect.[Resumen] El artículo describe el método y algunos de los resultados obtenidos en el laboratorio de Psicofisiología de la Universidad de La Coruña. El trabajo abarca nuestra investigación sobre el efecto Simon y sobre el efecto accesorio, aunque no es una revisión del corpus teórico. La estrategia de investigación seguida en estos experimentos se basa en la utilización de potenciales motores lateralizados que se registran sobre cuero cabelludo. Estas medidas permiten observar cómo y cuándo se seleccionan las respuestas, proporcionando una valiosísima herramienta para estudiar la interferencia de respuesta y para partir el tiempo de reacción en dos mitades. Nuestra investigación sobre el efecto Simon concluye que la interferencia durante la selección de respuesta es crucial en el efecto Simon, pero no está tan claro si este proceso debe considerarse automático y guiado por el estímulo, como defienden la mayoría de las teorías actuales. Los experimentos con el efecto accesorio indican que la facilitación se produce antes de que termine la selección de respuesta, lo que acaba con una larga controversia acerca del locus del efecto accesorio

Stimulus-response compatibility between stimulated eye and response location: implications for attentional accounts of the Simon effect

[Abstract] One influential theory of the Simon effect, the attention-shift hypothesis, states that attention movements are the origin of spatial stimulus codes. According to this hypothesis, stimulus-response compatibility effects should be absent when attention shifts are prevented. To test this prediction, we used monocular patches of color that required left or right key-press responses. About half of the subjects could discriminate which eye was stimulated (in a subsequent task), and showed strong spatial compatibility effects between the stimulated eye and the response location. The other half of the subjects could not make a utrocular discrimination (i.e., they could not judge which eye had received monocular stimulation), but the pattern of results was the same: the fastest reaction times were observed when the stimulated eye corresponded spatially to the required response (i.e., a Simon effect). Since the subjects presumably did not move their attention (from the subject's point of view, the stimuli were presented centrally), our results indicate that spatial codes can be produced in the absence of attention shifts. These results also show that utrocular discrimination can be assessed via indirect measures that are much more sensitive than explicit measures.Ministerio de Cultura (España); PR2002–007

Attention to Monocular Images Bias Binocular Rivalry

When monocular images cannot be fused, perception alternates between the two (or more) possible images. This phenomenon, binocular rivalry (BR), is driven by the physical properties of the stimuli (size, contrast, spatial frequency, etc.) but it can also be modulated by attention to features of one of the rival stimuli (Chong et al., 2005; Dieter et al., 2016) and by attentional demands independent of the BR assessment (Paffen et al., 2008). Instead of the perceptually demanding tasks previously used to bias BR, we designed a simple counting task. We monocularly presented a number of trials (around 10 min) with a set of symbols and asked participants to count them. We found that after this task, dominance durations decreased for the unattended channel, and did not change for the attended channel. The results parallel those of Paffen et al. (2008) and square nicely with Levelt’s second proposition, suggesting that the counting task effectively increased the sensibility of one channel which led to increased strength of the images presented to that channel. Alternatively, the results could be explained assuming that the non-attended channel was inhibited during the counting task, and the inhibition was carried over to the BR task

Psychophysiological studies of unattended information processing.

Sin resume

Universalidad de la expresión emocional e inferencia correcta

El artículo revisa las críticas que Iglesias y cols. (1984) hacen a otro trabajo (Valle-Inclán, 1983) y concluye que no hay lugar para la crítica. La controversia está alrededor del número de patrones faciales de la emoción universales. En mi artículo anterior se defendía que la evidencia sólo permite hablar de los grandes patrones universales de la expresión facial de las emociones, mientras que Iglesias y col., en la línea de muchos autores, defienden que se puede defender más patrones faciales universales.The article is an answer to the criticisms Iglesias et al. (1984) roused by another previous work (Valle-Inclán, 1983). The conclusion is that the critique has no base. The controversy stands over the number of universal facial patterns of emotions. In my previous article evidence only allowed us to talk about two universal patterns for facial expression of emotion, but Iglesias y cols., in line with many others, defend there are more than two universal facial patterns

Electrical activity in primary visual area due to interocular suppression

[Abstract] Under binocular rivalry conditions, evoked potentials to lower hemifield stimulation are more positive for the dominant than for the suppressed eye between 100 and 300 ms. However, this pattern reverses when the upper hemifield is stimulated, suggesting a neural source in V1 for this endogenous potential (rivalry-related potential, RRP). Here we investigated the functional significance of the RRP using an interocular suppression procedure. We replicated the RRP polarity reversal for upper versus lower hemifield stimulation and showed that the RRP reflects differences in processing during dominance and suppression and not shifts in dominance

Datos normativos de la escala de susceptibilidad hipnótica de stanford, forma c, en una muestra española

Se administró la versión española de la Escala de Susceptibilidad Hipnótica de Stanford, Forma C (SHSS:C; Weitzenhoffer and Hilgard, 1962) a 115 voluntarios. Se presentan los datos sobre puntuación media, distribución de las puntuaciones, dificultad de los ítems, fiabilidad y validez, y se comparan con los correspondientes a la muestra original americana. En general, los resultados de la versión española son muy similares a los publicados previament