DOI: 10.5061/dryad.2z34tmpmt
title: NIRS data during sandplay and interview

description: Interactions between the client (Cl) and therapist (Th) evolve therapeutic
 relationships in psychotherapy. An interpersonal link or therapeutic space
 is implicitly developed wherein certain important elements are expressed
 and shared.  However, neural basis of psychotherapy, especially
 of non-verbal modalities, have scarcely been explored. Therefore, we
 examined the neural backgrounds of such therapeutic alliances during
 sandplay, a powerful art/play therapy technique. Real-time and
 simultaneous measurement of hemodynamics was conducted in the prefrontal
 cortex (PFC) of Cl-Th pairs participating in sandplay and subsequent
 interview sessions through multichannel near-infrared spectroscopy. As
 sandplay is highly individualized, and no two sessions and products
 (sandtrays) are the same, we expected variation in interactive patterns in
 the Cl–Th pairs. Nevertheless, we observed a statistically significant
 correlation between the spatio-temporal patterns in signals produced by
 the homologous regions of the brains. During the sandplay condition,
 significant correlations were obtained in the lateral PFC and frontopolar
 (FP) regions in the real Cl-Th pairs. Furthermore, a significant
 correlation was observed in the FP region for the interview condition. The
 correlations found in our study were explained as a “remote”
 synchronization (i.e., unconnected peripheral oscillators synchronizing
 through a hub maintaining free desynchronized dynamics) between two
 subjects in a pair, possibly representing the neural foundation of empathy
 which arises commonly in sandplay therapy.
description: Six clients (Cls＝ healthy volunteer students) and six volunteer
 therapists (Ths) participated in this study. The age of Cls ranged from 19
 to 28 years (i.e., mean age = 21.5 years, SD = 2.99) and between 23 to 49
 years for Ths (i.e., mean age = 39.7 years, SD = 8.21). They formed six
 (one male-male, one male-female, four female-female) pairs; however, due
 to technical problems with NIRS data acquisition, one female-female pair
 was excluded from the analysis, and the remaining five pairs were
 analyzed. We used multichannel NIRS (FOIRE-3000;
 Shimadzu, Kyoto, Japan) to measure the time courses of concentration
 changes regarding oxy- and deoxy-Hb during a simulated sandplay session
 (i.e., 10 minutes at maximum) and post-sandplay interviews (i.e.,
 approximately 5 minutes). Near-infrared light was used at wavelengths of
 780 nm, 805 nm, and 830 nm, and the time resolution was set
 to 0.13 seconds. From the sandplay task period and the interview session,
 which lasted approximately 10 minutes, a sampling window of 200 seconds
 was selected for each session, with relatively stable signals, and without
 apparent artifacts.
description: Please use these datasets only for quantitative analyses. We are
 refraining from uploading the sandtrays (i.e. sandplay pictures ) made by
 the Cls, as no consents for analyzing their sandtrays in any other ways,
 such as interpreting the individual sandplayers' personalities or
 psychological problems which might be presented in their
 sandtrays. In the first column,
 task-start indicates the starting point of sandtray
 task-end indicates the end poing of sandtray
 interview-start indicates the starting point of
 interview interview-end indicates the end point of
 interview The graphs of NIRS signals and heatmaps were
 obtained using the R script "analysis6_Study1_task_20180914.R "
 and "analysis7_Study1_interview_20180914.R", and the
 cross-correlograms were obtained by
 "correlogramviewer1.R".