The unnoticed zoo: Inattentional deafness to animal sounds in music.

Inattentional unawareness potentially occurs in several different sensory domains but is mainly described in visual paradigms ("inattentional blindness"; e.g., Simons & Chabris, 1999, Perception, 28, 1059-1074). Dalton and Fraenkel (2012, Cognition, 124, 367-372) were introducing "inattentional deafness" by showing that participants missed by 70% a voice repeatedly saying "I'm a Gorilla" when focusing on a primary conversation. The present study expanded this finding from the acoustic domain in a multifaceted way: First, we extended the validity perspective by using 10 acoustic samples-specifically, excerpts of popular musical pieces from different music genres. Second, we used as the secondary acoustic signal animal sounds. Those sounds originate from a completely different acoustic domain and are therefore highly distinctive from the primary sound. Participants' task was to count different musical features. Results (N = 37 participants) showed that the frequency of missed animal sounds was higher in participants with higher attentional focus and motivation. Additionally, attentional focus, perceptual load, and feature similarity/saliency were analyzed and did not have an influence on detecting or missing animal sounds. We could demonstrate that for 31.2% of the music plays, people did not recognize highly salient animal voices (regarding the type of acoustic source as well as the frequency spectra) when executing the primary (counting) task. This uncovered, significant effect supports the idea that inattentional deafness is even available when the unattended acoustic stimuli are highly salient.

Happiness takes you right: the effect of emotional stimuli on line bisection.

Emotion recognition is mediated by a complex network of cortical and subcortical areas, with the two hemispheres likely being differently involved in processing positive and negative emotions. As results on valence-dependent hemispheric specialisation are quite inconsistent, we carried out three experiments with emotional stimuli with a task being sensitive to measure specific hemispheric processing. Participants were required to bisect visual lines that were delimited by emotional face flankers, or to haptically bisect rods while concurrently listening to emotional vocal expressions. We found that prolonged (but not transient) exposition to concurrent happy stimuli significantly shifted the bisection bias to the right compared to both sad and neutral stimuli, indexing a greater involvement of the left hemisphere in processing of positively connoted stimuli. No differences between sad and neutral stimuli were observed across the experiments. In sum, our data provide consistent evidence in favour of a greater involvement of the left hemisphere in processing positive emotions and suggest that (prolonged) exposure to stimuli expressing happiness significantly affects allocation of (spatial) attentional resources, regardless of the sensory (visual/auditory) modality in which the emotion is perceived and space is explored (visual/haptic).

Creating a framework for experimentally testing early visual processing: a response to Nurmoja, et al. (2012) on trait perception from pixelized faces.

Nurmoja, Eamets, Härma, and Bachmann (2012) revealed that strongly pixelated pictures of faces still provide relevant cues for reliably assessing the apparent (i.e., subjectively perceived) traits of the portrayed. The present article responds to the paper by developing the outline of a framework for future research to reveal certain steps in processing complex visual stimuli. This framework combines the approach of degradation of the stimuli with the so-called microgenetic approach of percepts based on presentation time limitations. The proposed combination of a particular kind of stimulus manipulation and a specific experimental procedure allows testing targeted assumptions concerning visual processing, not only in the domain of face perception, but in all domains involving complex visual stimuli, for example, art perception.

The paddle move commonly used in magic tricks as a means for analysing the perceptual limits of combined motion trajectories.

Following Gustav Kuhn's inspiring technique of using magicians' acts as a source of insight into cognitive sciences, we used the 'paddle move' for testing the psychophysics of combined movement trajectories. The paddle move is a standard technique in magic consisting of a combined rotating and tilting movement. Careful control of the mutual speed parameters of the two movements makes it possible to inhibit the perception of the rotation, letting the 'magic' effect emerge--a sudden change of the tilted object. By using 3-D animated computer graphics we analysed the interaction of different angular speeds and the object shape/size parameters in evoking this motion disappearance effect. An angular speed of 540 degrees s(-1) (1.5 rev. s(-1)) sufficed to inhibit the perception of the rotary movement with the smallest object showing the strongest effect. 90.7% of the 172 participants were not able to perceive the rotary movement at an angular speed of 1125 degrees s(-1) (3.125 rev. s(-1)). Further analysis by multiple linear regression revealed major influences on the effectiveness of the magic trick of object height and object area, demonstrating the applicability of analysing key factors of magic tricks to reveal limits of the perceptual system.

Visual mental imagery in congenital prosopagnosia.

Congenital prosopagnosia (cPA) is a selective impairment in the visual learning and recognition of faces without detectable brain damage or malformation. There is evidence that it can be inherited in an autosomal dominant mode of inheritance. We assessed the capacity for visual mental imagery in 53 people with cPA using an adapted Marks' VVIQ (Vividness of Visual Imaging Questionnaire). The mean score of the prosopagnosic group showed the lowest mental imagery scores ever published for a non-brain damaged group. In a subsample of 12 people with cPA, we demonstrated that the cPA is a deficit of configural face processing. We suggest that the 'VVIQ-PA' (VVIQ-Prosopagnosia) questionnaire can help to confirm the diagnosis of cPA. Poor mental imagery, a configural face processing impairment and clinical prosopagnosia should be considered as symptoms of a yet poorly understood hereditary cerebral dysfunction.