TY - JOUR
T1 - Continuous Transition Impairs Discrimination of Electrotactile Frequencies
AU - Gholinezhad, Shima
AU - Dosen, Strahinja
AU - Dideriksen, Jakob
PY - 2022/10/1
Y1 - 2022/10/1
N2 - Just-noticeable difference (JND), indicating the ability to accurately identify small differences in stimulation parameters, can be used to choose more sensitive stimulation methods as well as to calibrate tactile feedback in closed-loop human-machine interfacing. The JND is typically estimated using a forced-choice-discrimination task, in which two stimuli with different intensities are delivered separated by a brief pause. In the applications of tactile feedback, however, the stimulation parameters are typically modulated continuously. It is unclear if the discriminability of stimuli separated in time characterizes the ability to distinguish continuous changes in stimulation intensity. The present study compared the JND when pairs of frequency-modulated electrotactile stimuli were separated in time and presented continuously at two different baseline frequencies (20 and 60 Hz). The results showed that the JND was significantly smaller with time-separation between stimuli, but that the JND obtained with different types of transitions were in most cases linearly associated. In conclusion, the discriminability of time-separated stimuli is systematically better compared to that of the stimuli presented continuously. This can have an impact when calibrating the tactile feedback where the conventional method of the JND assessment might lead to an overly optimistic estimate of detectable changes.
AB - Just-noticeable difference (JND), indicating the ability to accurately identify small differences in stimulation parameters, can be used to choose more sensitive stimulation methods as well as to calibrate tactile feedback in closed-loop human-machine interfacing. The JND is typically estimated using a forced-choice-discrimination task, in which two stimuli with different intensities are delivered separated by a brief pause. In the applications of tactile feedback, however, the stimulation parameters are typically modulated continuously. It is unclear if the discriminability of stimuli separated in time characterizes the ability to distinguish continuous changes in stimulation intensity. The present study compared the JND when pairs of frequency-modulated electrotactile stimuli were separated in time and presented continuously at two different baseline frequencies (20 and 60 Hz). The results showed that the JND was significantly smaller with time-separation between stimuli, but that the JND obtained with different types of transitions were in most cases linearly associated. In conclusion, the discriminability of time-separated stimuli is systematically better compared to that of the stimuli presented continuously. This can have an impact when calibrating the tactile feedback where the conventional method of the JND assessment might lead to an overly optimistic estimate of detectable changes.
KW - Electrodes
KW - Estimation
KW - Frequency estimation
KW - Frequency modulation
KW - Prosthetics
KW - Tactile sensors
KW - Time-frequency analysis
KW - Just-noticeable difference
KW - psychometrics assessment
KW - human-machine interfaces
KW - electrotactile stimulation
KW - frequency modulation
UR - http://www.scopus.com/inward/record.url?scp=85139433379&partnerID=8YFLogxK
U2 - 10.1109/TOH.2022.3208332
DO - 10.1109/TOH.2022.3208332
M3 - Journal article
VL - 15
SP - 753
EP - 758
JO - IEEE Transactions on Haptics
JF - IEEE Transactions on Haptics
SN - 1939-1412
IS - 4
M1 - 9896868
ER -