1Brain Center for Social and Motor Cognition, Italian Institute of Technology, Parma, Italy; 2Department of ... of the contact between the tool and its target object.
The specificity of the supramarginal tool use observation area in intracerebral recordings F. 1Brain
1,2 Caruana ,
P.
2 Avanzini ,
I.
4 Sartori ,
V.
3 Pelliccia ,
G.
3 Casaceli ,
G. Lo
3 Russo ,
G.
1,2 Rizzolatti ,
G. A.
2 Orban
Center for Social and Motor Cognition, Italian Institute of Technology, Parma, Italy; 2Department of Neuroscience, University of Parma, Parma, Italy; 3Claudio Munari Center for Epilepsy Surgery, Ospedale Niguarda-Ca’ Granda, Milan, Italy
Introduction
aSMG activity synchronizes with the tool entrance
334.15/FF13
Differences between aSMG and dSMG
The Inferior Parietal Lobe (IPL) has been classically considered as a key region for the use of tools. A long list of imaging studies indicate that the anterior IPL is activated by tool action observation, sounds produced by tools, as well as by executing tool actions, imaging or pantomiming tool use or making decisions about tool
BA6
use (Lewis et al. 2005; Binkofski et al. 1998; Chao and Martin 2000; Okada et al. 2000.; Inoue et al. 2001; Rumiati et al. 2004; Johnson-Frey et al. 2005; Valyear et al. 2007; Jacobs et al. 2009; Króliczak and Frey 2009;
POIPS
Gallivan et al. 2013; Brandi et al. 2014), and apraxia for tools and disrupted pantomimed tool use are typically
VIPS
DIPSM DIPSA
observed after the lesion of the left IPL (Buxbaum et al. 2014; Goldenberg & Spatt 2009; Osiurak et al. 2010).
phAIP
Recently we suggested that only a part of the left IPL, i.e. the anterior Supramarginal Gyrus (aSMG), is
selectively involved in tool use observation (Peeters et al. 2009, 2013; see Orban & Caruana 2014; Orban & Rizzolatti 2012). The main objective of the study was to assess the selectivity of the aSMG to the observation of
MT cluster
tool action, by analyzing the intracranially recorded high gamma power (50-150Hz), which is considered to be a reliable marker of the neuronal activity (Ray et al. 2008), showing a very high spatial and temporal resolution.
Data collection
Intracranial stereo-EEG (sEEG) was collected from 34 hemispheres (R=15, L=19) in 31 epileptic patients with depth electrodes implanted as part of their presurgical evaluation, at the Claudio Munari Center for Epilepsy Surgery, Ospedale Niguarda-Ca’ Granda, Milan, Italy. Patients observed videos depicting actions performed with different tools or with the hand, as well as static images extracted from the movies as controls. Stimuli were previously employed in fMRI studies (Peeters et al., 2009). For each video we identified the precise timing of the appearance of the tool and that of the contact between the tool and its target object.
Among responsive sites (L=875; R=607), we selected those of which activity was triggered by the appearance of the tool
Besides aSMG, we identified an additional component of the tool action observation network in dSMG, located between aSMG and phAIP. Dorsal
in the video (Yellow), and not by the video onset or by the contact between the tool and the object (Black). The tool
SMG differed from its twin area aSMG by (a) its selectivity to the specific identity of tools (i.e. rake, pliers, screwdriver. Not shown) and (b) its
appearance network included, in left hemisphere, aSMG and dorsal SMG (dSMG), PMv, MT cluster, and pMTG
activation during the observation of tool images in addition to tool action observation.
(L=123), and a small number of right sites (R=35). The left lateralization of sites responding to the appearance of the tool
Contacts 7-12, recovered from the same patient, show (a) an activation for tool actions but not for hand actions in both aSMG and dSMG, but (b) an
was confirmed by a chi-squared test (p