The authors of a new paper note that "one of the principal ways in which we interact using our faces is kissing." This reminds me of an old National Lampoon joke on how the French were famous for inventing sex acts with the face. But I digress.
This paper looks at neural imaging responses of subjects who observe, in photographs, various kinds of kissing. The two main variables are who is kissing (by gender) and the nature of the kiss.
From the abstract of the paper:
With a few exceptions, the literature on face recognition and its neural basis derives from the presentation of single faces. However, in many ecologically typical situations, we see more than one face, in different communicative contexts. ... Although there is no obvious taxonomy of kissing, we kiss in various interpersonal situations (greeting, ceremony, sex), with different goals and partners. Here, we assess the visual cortical responses elicited by viewing different couples kissing with different intents. The study thus lies at the nexus of face recognition, action recognition, and social neuroscience. Magnetoencephalography data were recorded from nine participants in a passive viewing paradigm. We presented images of couples kissing, with the images differing along two dimensions, kiss type and couple type. We quantified event-related field amplitudes and latencies. In each participant, the canonical sequence of event-related fields was observed, including an M100, an M170, and a later M400 response. The earliest two responses were significantly modulated in latency (M100) or amplitude (M170) by the sex composition of the images (with male-male and female-female pairings yielding faster latency M100 and larger amplitude M170 responses). In contrast, kiss type showed no modulation of any brain response. The early cortical-evoked fields that we typically associate with the presentation and analysis of single faces are differentially sensitive to complex social and action information in face pairs that are kissing. The early responses, typically associated with perceptual analysis, exhibit a consistent grouping and suggest a high and rapid sensitivity to the composition of the kissing pairs.
Interesting research, part of the bigger picture of how human perception operates in an important social context. I asked Shiril Kirshenbaum for a quick comment and she told me that one of the most interesting parts of this work is "that usually we think of science writing as something that happens after research or discovery. But here we have a nice example demonstrating that the relationship can go both ways where new science has been driven by the storytelling."
A kiss is not a kiss: visually evoked neuromagnetic fields reveal differential sensitivities to brief presentations of kissing couples. 2015. Cogan, Gregory, Sheril Kirshenbaum, Jeffry Walker, and David Poeppel. NeuroReport, August 18, 2015.