Fig 1.
Locations of the NIRS channels.
(A) Arrangement of the 17 emitters and 16 detectors and definition of the channels. (B) The anatomical site corresponding to each channel.
Fig 2.
Design of the verbal fluency task.
Table 1.
Demographic, clinical, and neuropsychological characteristics of suicide attempters, non-attempters, and healthy controls.
Fig 3.
The grand-averaged waveforms of changes in the oxy-Hb signal in suicide attempters, non-attempters, and healthy controls.
Table 2.
Comparison of regional hemodynamic responses of suicide attempters, non-attempters, and healthy control subjects threshold of p < 0.00096.
Fig 4.
The differential time course of the oxy-Hb signal in the left precentral gyrus in suicide attempters, non-attempters, and healthy controls.
(A) The anatomical site corresponding to channel 9 (left precentral gyrus). (B) Dot plots of mean oxy-Hb changes of the left precentral gyrus in SAs, NAs, and HCs. (C) The differential time course of oxy-Hb signal in SAs, NAs, and HCs in the left precentral gyrus. In NAs and HCs, the time course of changes in the oxy-Hb signal showed a gradual increase followed by a gradual decrease after the end of the task; SAs did not exhibit this response. The dashed red lines indicate standard deviations for each group. Abbreviations: HCs, healthy controls; NAs, non-attempters; SAs, suicide attempters **p < 0.01
Fig 5.
Correlation between hemodynamic responses and impulsivity, aggression, and hopelessness in suicide attempters and non-attempters.
The reduced response in the left inferior frontal gyrus was negatively correlated with impulsivity level and the responses in the right middle frontal gyrus were negatively associated with hopelessness and aggression in suicide attempters (SAs) but not in non-attempters (NAs).