Beatscope 1

We continuously measured heart rate (HR) using a lead II electrocardiogram (bedside monitor, BMS‐2401; Nihon Kohden, Japan) and beat‐to‐beat arterial blood pressure using finger photoplethysmography (Finapres Medical Systems BV, Netherlands). We determined stroke volume (SV) from the blood pressure waveform using the Modelflow software program, which incorporates the sex, age, height, and weight of the subject (Beat Scope1.1; Finapres Medical Systems BV). We analyzed P_ETCO₂ from respiratory gas sampled via a leak‐free mask using a gas analyzer (AE‐310S; Minato Medical Science Co.).

Heart rate was monitored using three‐lead electrocardiography (BSM2301; Nihon Kohden). Continuous arterial blood pressure was monitored using finger photoplethysmography (Finometre MIDI; Finapres Medical System), and used to calculate mean arterial pressure (MAP). Stroke volume (SV) and cardiac output were determined from the ABP waveform using the Modelflow software program, which incorporates the sex, age, height, and weight of the subject (Beat Scope1.1; Finapres Medical Systems). The partial pressure of carbon dioxide (PetCO₂) was measured using a capnometer (CO₂ Monitor OLG‐2800A; Nihon Kohden).

The heart rate (HR) was measured using a lead II electrocardiogram (bedside monitor, BMS‐3400; Nihon Kohden, Japan). The beat-to-beat arterial blood pressure was monitored continuously using finger photoplethysmography (Finapres Medical Systems, Amsterdam, The Netherlands) to determine the systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP). The stroke volume (SV) was determined from the BP waveform using the Modelflow software program, which incorporates the sex, age, height, and weight of the subject (Beat Scope1.1; Finapres Medical Systems BV). The cardiac output (CO) was calculated by the SV multiplied by the HR. The P_ETCO₂, minute ventilation (V_E), and RR were sampled from a leak-free mask and measured with a gas analyzer (AE-310S; Minato Medical Science Co., Osaka, Japan). Cerebral blood velocity in the right MCA (MCAv) and left PCA (PCAv) were measured as an index of anterior and posterior CBF, respectively, using a 2-MHz pulsed transcranial Doppler (TCD) probe (DWL Doppler Box-X; Compumedics, Germany). The TCD probe was fixed and held in place using a headband.
Participants were asked to indicate their pain level immediately after a CPT on a 10 cm visual analog scale (VAS). The VAS for pain intensity was anchored with “no pain” at one end and “severe pain” at the other end [17 (link)].

The cardiovascular responses during exposures to emotionally charged movies were examined in 13 of the 14 subjects. A pair of electrodes (Magnerode, TE‐18M‐3, Fukuda Denshi, Tokyo, Japan) and a ground electrode were attached on the chest for measuring electrocardiogram (ECG). The ECG signal and respiratory movement were monitored with a telemetry system (DynaScope DS‐3140, Fukuda Denshi, Tokyo, Japan). AP was noninvasively and continuously measured with a Finometer (Finapres Medical Systems BV, Arnhem, the Netherlands), of which a cuff was attached to the left middle or index finger. The AP waveform was sampled at a frequency of 200 Hz. The beat‐to‐beat values of mean AP (MAP), HR, cardiac output (CO), stroke volume (SV), and total peripheral resistance (TPR) were calculated from the aortic pressure waveform by using a Modelflow software (BeatScope 1.1, Finapres Medical Systems BV, Arnhem, the Netherlands).

An electrocardiogram (ECG) was monitored with a telemetry system (DynaScope DS‐3140, Fukuda Denshi, Tokyo, Japan). Arterial blood pressure (AP) was noninvasively and continuously measured with a Finometer^® (Finapres Medical Systems BV, Arnhem, the Netherlands), whose cuff was attached to the left middle or index finger. The AP waveform was sampled at a frequency of 200 Hz. The beat‐to‐beat values of mean AP (MAP) and heart rate (HR) were obtained throughout the experiments. Simultaneously, the beat‐to‐beat values of cardiac output (CO), stroke volume (SV), and total peripheral resistance (TPR) were calculated from aortic pressure waveform by using a Modelflow^® software (BeatScope 1.1, Finapres Medical Systems BV, Arnhem, the Netherlands).
Electromyogram (EMG) activity of the non‐contracting arm muscles was measured using a pair of silver‐bar electrodes attached near the probes of NIRS (Bagnoli‐2 and 4 EMG Systems, Delsys, Boston, MA). EMG activity was also recorded in the contracting arm muscles in four subjects. The EMG signals were amplified (×10000) and passed through a bandpass filter between 20 and 2000 Hz.