There is No test–retest reliability of brain activation induced by robotic passive hand movement: A functional NIRS study

Abstract

Does the brain activation induced by the robotic passive movement have TRR? Focusing on this simple question, the present paper attempts to provide an answer to it. The importance and background of this question are provided as follows. The brain plasticity, the ability of the brain system to reorganize its structure and function, is the basic mechanism for restoring motor function in stroke patients (Cramer et al., 2011; Murphy & Corbett, 2009; Schaechter, 2004). Recovery of motor function by brain plasticity is made by modulating the brain activation through the manipulation of the external stimuli (Kaplan, 1988).

Test-retest reliability of functional near-infrared spectroscopy during a finger-tapping and postural task in healthy older adults

“…Previous investigations on fNIRS test-retest reliability did not report on the stability of the behavioral correlates 20 – 24 , 26 , 27 Four of these studies (study 1, 2, 5, and 6 in Table 4) standardized performance to some extent to prevent a learning effect, for instance by using cues, 22 robotic passive hand movements, 21 practicing the task with a metronome, 20 or using a very small time-window (1200 ms) 24 . Furthermore, one study (study 3 in Table 4) checked for possible differences in exhaustion via a Borg scale, showing no differences between test moments 26 …”

“… – 19 Seven studies investigated fNIRS test-retest reliability of the PFC or the contralateral motor cortex during motor tasks, based on the intraclass correlation coefficient (ICC) 20 – 24 The ICC provides an overall estimate of the correlation and agreement between measurements. It is calculated as the proportion of between-subject variance over the total variance 25 .…”

“…Four studies reported good to excellent reliability during manual tasks (ICC≥0.60), of which two studied task-specific motor channels (ICC≥0.62) 20 , 22 . One study reported very poor test-retest reliability (ICC=0.002) during passive hand movements imposed by a robot 21 . Only two studies investigated test-retest reliability during gait-related tasks, 26 , 27 showing fair to good reliability for straight walking (ICC>0.40; 26 ICC=0.71 27 ) and turning (ICC=0.67 27 ) in the PFC in young and middle-aged adults.…”

Sex Differences in the Oxygenation of the Left and Right Prefrontal Cortex during Moderate-Intensity Exercise

“…O 2 Hb and HHb data were averaged at each channel, and a 0.1-Hz low pass filter was used to decrease noise from the heartbeat [ 46 , 47 ]. As previously described [ 48 , 49 ], cerebral hemoglobin concentration was measured using three differential continuous waves (780 nm, 804 nm, and 830 nm), based on the Modified Beer–Lambert Law [ 50 ], with absorbance at the start of measurement was defined as the initial absorbance of each wavelength. As it was not possible to measure the differential path-lengths using the continuous-wave NIRS system, absorbance was assumed to be a constant, with changes in the hemoglobin signal denoted in arbitrary units (mM·cm) [ 51 , 52 ].…”

Relationship between the Difference in Oxygenated Hemoglobin Concentration Changes in the Left and Right Prefrontal Cortex and Cognitive Function during Moderate-Intensity Aerobic Exercise

“…O2Hb data were averaged at each channel, and a 0.1 Hz low pass filter was used to decrease noise from the heartbeat [59,60]. The device used in this study and in previous studies [61,62] can measure the cerebral hemoglobin concentration using three differential continuous waves (780 nm, 804 nm, and 830 nm), and is based on the modified Beer-Lambert law [63]. That is because, for each wavelength, absorbance at the start of measurement was defined as the initial absorbance.…”