Experiments in vertebrates offer indications of the complexity of neuromodulatory signaling as the beneficial effects of NE and DA receptor stimulation arise from opposing effects on cAMP intracellular signaling pathways; NE α2A receptor binding inhibits [58] while DA-D1 receptor binding activates [59] these pathways.
For example, a hexagonal column in the primate somatosensory cortex is about 400 μm in width and contains populations of neurons that respond to the same stimulus (e.g. light touch or joint stimulation) arising from a specific topographical zone of the body.
Hui et al. found deqi response of acupoint stimulation likely arises from A-delta and C-fiber stimulation by the needle [ 30].
In contrast, type II carcinomas are unrelated to oestrogenic stimulation and arise in a background of atrophic endometrium.
Both trains always started and ended at the same time for all conditions, to prevent any extended periods with only unimodal stimulation from arising during the asynchronous conditions, and to ensure that the initial-onset, final-offset, and duration was identical for all trains in all experimental conditions.
Transcriptional stimulation could arise in response to accumulation of lysosomal storage and the need for increased lysosomal biogenesis, a response that has recently been shown to be coordinated by the transcription factor TFEB (Sardiello and Ballabio, 2009; Sardiello et al., 2009).
The effect that the subject works to reinstate, called "brain stimulation reward" (BSR), arises from an observable train of nerve impulses, triggered at a brain site chosen by the experimenter; the strength and timing of this volley can be controlled with great precision.
For example, biophysical models, such as those instantiated in dynamic causal models (DCMs), can in principle help to test whether remote stimulation effects predominantly arise from ortho- and/or antidromic stimulation of connections, and/or via pyramidal projections or intra-regional interneurons.
Pain also arises from stimulation of the white matter deep in the cerebral cortex.
