Study 2 investigated two possible mechanisms of such asymmetry by (a) using contralateral white noise masking to activate the medial olivocochlear system and (b) increasing stimulus rate to reveal neural conduction and synaptic mechanisms.
In most fascicles however a decrease in the excitability index of Cfibres can be induced by increasing stimulus rate (Figure 3B, 4 & 5).
In general, the magnitude of the excitability index change produced by GABA (30 µM) or muscimol (30 µM) increases with increasing basal stimulus rate, i.e. as the prevailing excitability index decreases (Figure 3C & 5D).
With the market divided on whether the Bank of Japan would increase stimulus or cut rates further, Governor Kuroda decided to think outside the box and scrapped their set monetary base goal with the intent of targeting yields of various maturities, thereby creating a steeper yield curve.
It has been argued that the changes in the responses to individual stimuli with increasing stimulation rates provide evidence in favour of the non-linearity of the SSR and, consequently, against the linear mechanism postulated by the superposition theory [35].
Increasing the stimulus rate to 1 Hz, further reduces the prevailing excitability index and thereby increases the magnitude of change in excitability index evoked by GABA (10 µM).
Further support for the notion that GABA depolarises unmyelinated axons is the observation that C-fibre responses to GABA increase with stimulus rate (Figure 3).
However, an increase in the stimulus rate to 0.5 Hz reduced the prevailing excitability index and resulted in a corresponding increase in the magnitude of excitability index change observed in response to GABA (10 µM).
Even though both countries implemented a temporary "fiscal stimulus," their tax rate dynamics were different: the U.S. stimulus increased rates, whereas the U.K. stimulus reduced them.
In particular, the pulvinar nucleus of the posterior thalamus has shown activation in functional MRI and positron emission tomography studies on attention [24], [25], and single-cell recordings of pulvinar neurons in monkeys during attention tasks have shown increased firing rate to visual stimuli [26].
