Balancing the 2 Hemispheres in Simple Calculation: Evidence From Direct Cortical Electrostimulation

Semenza, Carlo; Salillas, Elena; Pallegrin, S. De; Puppa, Alessandro Della

doi:10.1093/cercor/bhw277

Cited by 17 publications

(41 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Our results demonstrated a high degree of selectivity for calculations in a network comprised of the aIPS and SPL in the LPC and the pITG in the VTC, almost completely dissociated from the selectivity observed during sentence comprehension (Memory condition), observed in the angular gyrus and STS and the medial inferior temporal cortex, known to be involved in language comprehension (Pallier et al, 2010) and reading (Hannagan, Amedi, Cohen, Dehaene-Lambertz, & Dehaene, 2015), respectively. This dissociation in line with previous reported iEEG results (Daitch et al, 2016;Hermes et al, 2015), with a recent fMRI study that used an analogous task (Amalric & Dehaene, 2016), with a series of prior fMRI findings (Arsalidou & Taylor, 2011) and with studies that used intraoperative electrical stimulation (Della Puppa et al, 2013;Semenza et al, 2017).…”

Section: Discussionsupporting

confidence: 86%

“…The classical Triple-Code model for numerical cognition proposed that the lateral parietal cortex (LPC) hosts the main hubs for numerosity representation and manipulation (Dehaene, Piazza, Pinel, & Cohen, 2003;Piazza, Izard, Pinel, Le Bihan, & Dehaene, 2004;Piazza, Pinel, Le Bihan, & Dehaene, 2007;Pinel, Dehaene, Rivie, & Lebihan, 2001). Indeed, convergent brain-imaging, intracranial recording and stimulation studies have found that the intraparietal sulcus (IPS) is selectively activated (Menon, Rivera, White, Glover, & Reiss, 2000;Stanescu-Cosson et al, 2000) and causally involved in mental arithmetic (Della Puppa et al, 2013;Semenza, Salillas, De Pallegrin, & Della Puppa, 2017). Furthermore, IPS activity has also been shown to increase as problems become harder (De Smedt, Holloway, & Ansari, 2011;Dehaene, Spelke, Pinel, Stanescu, & Tsivkin, 1999;Kanjlia, Lane, Feigenson, & Bedny, 2016;Molko et al, 2003;Visscher et al, 2015), thus paralleling the classical behavioral problem-size effect, which is an increase in calculation time as a function of the magnitude of the operands (Ashcraft, 1992).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Brain Mechanisms of Arithmetic: A Crucial Role for Ventral Temporal Cortex

Pinheiro‐Chagas

Daitch

Parvizi

et al. 2018

Journal of Cognitive Neuroscience

View full text Add to dashboard Cite

Elementary arithmetic requires a complex interplay between several brain regions. The classical view, arising from fMRI, is that the intraparietal sulcus (IPS) and the superior parietal lobe (SPL) are the main hubs for arithmetic calculations. However, recent studies using intracranial electroencephalography have discovered a specific site, within the posterior inferior temporal cortex (pITG), that activates during visual perception of numerals, with widespread adjacent responses when numerals are used in calculation. Here, we reexamined the contribution of the IPS, SPL, and pITG to arithmetic by recording intracranial electroencephalography signals while participants solved addition problems. Behavioral results showed a classical problem size effect: RTs increased with the size of the operands. We then examined how high-frequency broadband (HFB) activity is modulated by problem size. As expected from previous fMRI findings, we showed that the total HFB activity in IPS and SPL sites increased with problem size. More surprisingly, pITG sites showed an initial burst of HFB activity that decreased as the operands got larger, yet with a constant integral over the whole trial, thus making these signals invisible to slow fMRI. Although parietal sites appear to have a more sustained function in arithmetic computations, the pITG may have a role of early identification of the problem difficulty, beyond merely digit recognition. Our results ask for a reevaluation of the current models of numerical cognition and reveal that the ventral temporal cortex contains regions specifically engaged in mathematical processing.

show abstract

Section: Discussionsupporting

confidence: 86%

Section: Introductionmentioning

confidence: 99%

Brain Mechanisms of Arithmetic: A Crucial Role for Ventral Temporal Cortex

Pinheiro‐Chagas

Daitch

Parvizi

et al. 2018

Journal of Cognitive Neuroscience

View full text Add to dashboard Cite

show abstract

“…The finding of operation-specific positive sites in the right parietal lobe speaks against such a hypothesis. If inhibiting a site provokes a generic shortage of processing capacity, the effect would hold irrespective of the operation and would not be as operation-consistent as found with DCE in Semenza et al [75].…”

Section: Discussionmentioning

confidence: 72%

“…Positive sites for each patient assessed in[75]. A site was considered positive if the patient committed at least two out of three errors under DCE stimulation.…”

mentioning

confidence: 99%

Reassessing lateralization in calculation

Semenza

Benavides-Varela

2018

Phil. Trans. R. Soc. B

View full text Add to dashboard Cite

The role of the left hemisphere in calculation has been unequivocally demonstrated in numerous studies in the last decades. The right hemisphere, on the other hand, had been traditionally considered subsidiary to the left hemisphere functions, although its role was less clearly defined. Recent clinical studies as well as investigations conducted with other methodologies (e.g. neuroimaging, transcranial magnetic stimulation and direct cortical electro-stimulation) leave several unanswered questions about the contribution of the right hemisphere in calculation. In particular, novel clinical studies show that right hemisphere acalculia encompasses a wide variety of symptoms, affecting even simple calculation, which cannot be easily attributed to spatial disorders or to a generic difficulty effect as previously believed. The studies reported here also show how the right hemisphere has its own specific role and that only a bilateral orchestration between the respective functions of each hemisphere guarantees, in fact, precise calculation. Vis-à-vis these data, the traditional wisdom that attributes to the right hemisphere a role mostly confined to spatial aspects of calculation needs to be significantly reshaped. The question for the future is whether it is possible to precisely define the specific contribution of the right hemisphere in several aspects of calculation while highlighting the nature of the cross-talk between the two hemispheres.This article is part of a discussion meeting issue 'The origins of numerical abilities'.

show abstract

“…With the same goal, recent studies conducted with direct cortical electrostimulation (DCE) found a role of specific RH areas in simple addition and multiplication (Della Puppa et al, 2013;Della Puppa et al, 2015a;Della Puppa et al, 2015b;Duffau et al, 2002;Roux et al, 2009;Semenza et al, 2016) and subtractions (Yu et al, 2011). Finally, by means of a technique similar to rTMS and DCE (i.e., transcranial direct current stimulation, tDCS) and focusing on the acquisition of mathematical knowledge, Grabner and colleagues (2015) demonstrated that the left posterior parietal cortex is causally involved in arithmetic learning of two-digit operations.…”

Section: Introductionmentioning

confidence: 98%