Dr. Mustafa Nedim Göktepe

The perceived time can shrink or expand for emotional stimuli. Converging evidence suggests that emotional
time distortions are rooted in the emotional states of the timing agents because emotional stimuli can influence
the timing of simultaneous neutral events. As emotional states are transitory, we investigated if time modulating
emotional states also influence timing of subsequent neutral events. In each trial, we induced different valence
and arousal levels by using affective vibrotactile patterns before participants judged the duration of neutral
auditory tones. Compared to neutral patterns, affective patterns modulated participants’ time perception of the
subsequent tones. We observed an interaction between arousal and valence: Pleasant-Low arousal patterns
expanded the timing of subsequent neutral events more than Unpleasant-Low arousal patterns while Pleasant and
Unpleasant-High arousal led to a similar temporal expansion. Our results indicate time modulating effects of
emotional stimuli are due to changed emotional states and influence time perception likely until the underlying
state decays.

Previous studies have successfully elicited a wide range of emotional responses by stimulating the hand region. The purpose of the current study was to test whether tactile stimuli applied to the torso could elicit similar emotional responses. To this end, we created 45 custom vibrotactile patterns that were presented through a vibrotactile vest to the front, back, and both sides of the torso. The patterns covered a wide range of physical variables such as amplitude, trajectory, and continuity. In an exploratory experiment, participants rated the arousal and valence of these patterns. Emotional responses differed between the patterns, and detailed analyses suggested that vibration amplitude and intensity where these vibrations were applied influenced both valence and arousal judgments. In a follow-up experiment, we systematically varied the amplitude and location of the vibrations. Our results showed that lower amplitudes were less arousing and more pleasant than higher amplitudes. Similarly, vibrations to the back torso were less arousing and more pleasant than those applied to the front or both sides of the torso, which can be explained by the lower sensitivity on the back. Taken together, we suggest that perceived intensity partially explains the relationship between the emotionality of vibration patterns on the torso.