Effect of congruence between sound and video on heart rate and self-reported measures of emotion

Most studies of emotional responses have used unimodal stimuli (e.g., pictures or sounds) or congruent bimodal stimuli (e.g., video clips with sound), but little is known about the emotional response to incongruent bimodal stimuli. The aim of the present study was to evaluate the effect of congruence between auditory and visual bimodal stimuli on heart rate and self-reported measures of emotional dimension, valence and arousal. Subjects listened to pleasant, neutral, and unpleasant sounds, accompanied by videos with and without content congruence, and heart rate was recorded. Dimensions of valence and arousal of each bimodal stimulus were then self-reported. The results showed that heart rate depends of the valence of the sounds but not of the congruence of the bimodal stimuli. The valence and arousal scores changed depending on the congruence of the bimodal stimuli. These results suggest that the congruence of bimodal stimuli affects the subjective perception of emotion.

Eye Position Affects Audio — Visual Fusion in Darkness

We investigated the frame of reference involved in audio – visual (AV) fusion over space. This multisensory phenomenon refers to the perception of unity resulting from visual and auditory stimuli despite their potential spatial disparity. The extent of this illusion depends on the eccentricity in azimuth of the bimodal stimulus (Godfroy et al, 2003 Perception32 1233–1245). In a previous study, conducted in a luminous environment, Roumes et al 2004 ( Perception33 Supplement, 142) have shown that variation of AV fusion is gaze-dependent. Here we examine the contribution of ego- or allocentric visual cues by conducting the experiment in total darkness. Auditory and visual stimuli were displayed in synchrony with various spatial disparities. Subjects had to judge their unity (‘fusion’ or ‘no fusion’). Results showed that AV fusion in darkness remains gaze-dependent despite the lack of any allocentric cues and confirmed the hypothesis that the reference frame of the bimodal space is neither head-centred nor eye-centred.

The Significance of Some Spectral Features in Mating Call Recognition in the Green Treefrog (Hyla Cinerea)

1. Synthetic calls with a waveform periodicity of 300/sec and a bimodal spectrum attracted female green treefrogs as effectively as natural calls. 2. Effectiveness was markedly reduced if the relative amplitude of the two spectral peaks differed by as little as 10 dB. 3. Optimal frequency bands were 900-1100 Hz in the low range and 2700-3300 Hz in the high. 4. Addition of components at 1800 and 2100 Hz rendered the call less attractive. 5. In the absence of a bimodal stimulus, most females responded to a call containing a single spectral peak in the high or low range. 6. Mating call recognition in the green treefrog is compared with that in the bullfrog.