The Effect of Maximal Finger Tapping on Cerebral Activation

Abstract

The purpose of the present study was to investigate the effect of the repetition rate of a simple movement on the magnitude of neuronal recruitment at maximal effort in humans. Nine right-handed healthy subjects [age: 27.4Ϯ4.8 yr, stature: 174.5Ϯ12.2 cm, body-weight 74.3Ϯ16.6 kg (MeanϮSD)] participated in this study. We measured the regional cerebral hemodynamics using 24-channel near infrared spectroscopy (NIRS). An auditory-cued, repetitive flexion movement of the right index finger against a button was performed as the fingertapping task at maximal effort (ME), at 25% of maximal effort (25% ME) and at 50% of maximal effort (50% ME). The increase of the left primary motor cortex hemodynamics during movement relative to the hemodynamics under the resting condition was calculated for each pair of movement conditions. The frequency of finger-tapping was 1.61Ϯ0.18 Hz (25% ME trial), 3.23Ϯ0.36 Hz (50% ME trial), and 6.46Ϯ0.72 Hz (ME trial). The left primary motor cortex showed significant activation under all conditions. The change in total hemoglobin ([tHb]) between the ME trial and the resting value (1.19Ϯ0.93 mmol · mm) was significantly higher than those between the resting value and the 25% ME trial (0.04Ϯ0.04 mmol · mm) or the 50% ME trial (0.08Ϯ0.11 mmol · mm) (p<0.05). There was a 29.8-fold increase of the [tHb] value between the 50% ME trial and the ME trial, but only a 2-fold increase of the [tHb] value between the 25% ME trial and the 50% ME trial. These results demonstrated that the rate of change in regional cerebral hemoglobin at a maximal effort finger-tapping task was much higher than that at a low frequency finger-tapping task.

Assessment of the cerebral cortex during motor task behaviours in adults: A systematic review of functional near infrared spectroscopy (fNIRS) studies

“…Multichannel configurations have now been developed to enable measurement of simultaneous changes in cortical haemodynamics in several cortical locations (Contini et al, 2006;Everdell et al, 2005;Gibson et al, 2006) and more recently investigators have demonstrated whole head coverage . These systems have been utilised to determine the cortical region of maximal haemodynamic change (Durduran et al, 2004;Franceschini et al, 2003;Hirth et al, 1997;Kuboyama et al, 2004;Maki et al, 1996;Watanabe et al, 1996). Early studies were designed as block design experiments where stimuli are presented from a few seconds to several minutes followed by fixed episodes of rest.…”

“…There is evidence to suggest that the haemodynamic response can be modulated by the frequency (Kuboyama et al, 2004(Kuboyama et al, , 2005Obrig et al, 1996a), intensity (Shibusawa et al, 2009;Shibuya et al, 2008) and complexity (Holper et al, 2009) of the motor task or stimulus.…”

“…Data suggests that varying the intensity of motor performance, such as increasing the effort of button pressing (Kuboyama et al, 2004), hand grip or controlling the resistance load of finger tapping (Horovitz and Gore, 2003) modulates cortical haemodynamic changes, with higher intensity work leading to greater brain activation.…”

Balancing reward and work: Anticipatory brain activation in NAcc and VTA predict effort differentially

“…As button responses were non-normally distributed, we monotonically transformed the variable to an 'effort scale'. This was done by defining the maximum number of button presses throughout the experiment as 1 and assuming that effort increases quadratically with the number of button presses (i.e., reflecting the idea that motor activation increases more steeply for higher frequencies of finger tapping although the exact scaling is unknown; Kuboyama et al, 2004). This effectively normalized the distribution for the reward levels 10 and 100 but a second peak remained for the reward levels 0 and 1 around low numbers of button presses.…”

Temporal decoupling of oxy- and deoxy-hemoglobin hemodynamic responses detected by functional near-infrared spectroscopy (fNIRS)

“…Although previous fNIRS studies had revealed movement related hemodynamic response to motor tasks, most of these studies focused on repetitive motor activation tasks rather than directional arm movements. These studies included finger tapping or oscillator movements [7,[20][21][22][23][24], walking movements [25], movement imagery [26] and activity while solving an anagram task [27]. We will examine how hemodynamic responses in the motor cortex can be used to differentiate the difference between orthogonal arm movement directions by the temporal coupling/decoupling of oxy-and deoxy-Hb signals.…”