You're My Favorite Person...

Japanese actress and singer Ryoko Hirosue

...and watching your movies boosts my peripheral levels of dopamine and circulating natural killer cells, and activates my medial prefrontal cortex, thalamus, hypothalamus, subcallosal gyrus, posterior cingulate cortex, superior temporal gyrus, and cerebellum.


Fig. 3 (Matsunaga et al., 2008). Statistical parametric maps (SPM99) showing significant increases in the rCBF in the positive condition minus those in the control condition. (a) Activations of the MPFC and thalamus (TH). (b) Activations of the hypothalamus (HYP), subcallosal gyrus (SCG), and PCC. (c) Activations of the superior temporal gyrus (STG) and cerebellum (CER).



OK, so the "favorite person" alluded to in the title of the paper by Matsunaga et al. is really a favorite actress, not a favorite person IRL. The participants in the study were 12 healthy male volunteers, 20–29 years old. The stimuli were described by the authors as follows:

We compiled 4-min audiovisual clips. The positive film featured a person whom each participant subjectively considered attractive. By free response, the participants themselves selected this person before the day of the experiment. All the selected persons were famous actresses. By the day of the experiment, we compiled an individual 4-min video film from TV programs and movies for each participant. In order to demonstrate the maximum effect, we did not standardize the actions performed by the actresses in the movies, but the films did not contain erotic and sexually suggestive scenes. For example, one film contained scenes of the favorite person smiling. In addition, we compiled audiovisual clips because we thought that the favorite person’s voice was important for participants. The control film was a TV news program with a newscaster whom participants considered not so attractive. Since the newscaster being reported concerned weather in the past, rather than any new information, the participants remained uninterested in the film.

And the results? Watching your favorite actress is rewarding, and it apparently boosts your immune system too:

When the participants watched a film featuring an actress whom they considered attractive, they subjectively reported having experienced positive emotions. Interestingly, the activity of peripheral circulating NK cells as well as the peripheral circulating dopamine level significantly increased only under the positive condition. The following brain regions were significantly activated in the positive condition relative to the control condition: MPFC (BA 9/10), thalamus, hypothalamus, subcallosal gyrus (BA 25), PCC (BA 31), superior temporal gyrus (BA 38), and cerebellum. Further, SPM covariate analyses indicated that these brain regions were temporally associated with peripheral circulating NK cell activity and dopamine level. It was also indicated that the dopamine level was positively correlated with NK cell activity. These results suggest that while an individual experiences positive emotions, the central nervous, endocrine, and immune systems may be interrelated through neurochemical networks.

But what I really want to know is, what happens to your immune system when watching J-Horror films such as Ringu or Honogurai Mizu No Soko Kara (Dark Water)?


Watch one of Ryoko Hirosue's music videos. It was much less bubblegum Jpop¹ than I expected...

Footnote

¹ However, the first video in the YouTube J-Pop medley is called NightmaRe (by SNoW) and features a scary bunny furry wearing a gigantic clock.

Reference

MATSUNAGA, M., et al. (2008). Associations among central nervous, endocrine, and immune activities when positive emotions are elicited by looking at a favorite person. Brain, Behavior, and Immunity, 22(3), 408-417. DOI: 10.1016/j.bbi.2007.09.008

Recent studies on psychoneuroimmunology have indicated that positive psychological events are related to immune functions; however, limited information is available regarding associations among the central nervous, endocrine, and immune systems when positive emotions are elicited. In the present study, we demonstrated associations among these systems by simultaneously recording brain, endocrine, and immune activities when positive emotions were evoked in participants as they watched films featuring their favorite persons. Interestingly, the activity of peripheral circulating natural killer cells and the peripheral dopamine level were elevated while participants experienced positive emotions, and these values were positively correlated. The following brain regions were significantly activated in the positive condition relative to the control condition: medial prefrontal cortex, thalamus, hypothalamus, subcallosal gyrus, posterior cingulate cortex, superior temporal gyrus, and cerebellum. Further, covariate analyses indicated that these brain regions were temporally associated with endocrine and immune activities. These results suggest that while an individual experiences positive emotions, the central nervous, endocrine, and immune systems may be interrelated and attraction for favorite persons may be associated with the activation of the innate immune function via the dopaminergic system.