https://www.cell.com/neuron/pdf/S0896-6273(07)00460-6.pdf

Transcranial Magnetic Stimulation: A Primer

The development of sub-disciplines within cognitive neuroscience follows common sense categories such as language, audition, action, memory, emotion and perception among others. There are also well-established research programmes into temporal perception, spatial perception and mathematical cognition that also reflect the subjective impression of how experience is constructed. There is of course no reason why the brain should respect these common sense, text book divisions and, here, we discuss the contention that generalized magnitude processing is a more accurate conceptual description of how the brain deals with information about time, space, number and other dimensions. The roots of the case for linking magnitudes are based on the use to which magnitude information is put (action), the way in which we learn about magnitudes (ontogeny), shared properties and locations of magnitude processing neurons, the effects of brain lesions and behavioural interference studies. Here, we assess this idea in the context of a theory of magnitude, which proposed common processing mechanisms of time, space, number and other dimensions.

The parietal cortex and the representation of time, space, number and other magnitudes

Is 2+2=4? Meta-analyses of brain areas needed for numbers and calculations.

The use of transcranial magnetic stimulation in cognitive neuroscience: A new synthesis of methodological issues

The effect of strategies, goals and stimulus material on the neural mechanisms of emotion regulation: A meta-analysis of fMRI studies

Adult humans have the ability to count large numbers of successive stimuli exactly. What brain areas underlie this uniquely human process? To identify the candidate brain areas, we first used functional magnetic resonance imaging, and found that the upper part of the left ventral premotor cortex was preferentially activated during counting of successive sensory stimuli presented 10–22 times, while the area was not activated during small number counting up to 4. We then used transcranial magnetic stimulation to assess the necessity of this area, and found that stimulation of this area preferentially disrupted subjects’ exact large number enumeration. Stimulation to the area affected neither subjects’ number word perception nor their ability to perform a non-numerical sequential letter task. While further investigation is necessary to determine the precise role of the left ventral premotor cortex, the results suggest that the area is indispensably involved for large number counting of successive stimuli, at least for the types of tasks in this study.

Keiji Matsuda

Papers

The role of the human ventral premotor cortex in counting successive stimuli.