Sandrine Cremona

Bio: Sandrine Cremona is an academic researcher from University of Bordeaux. The author has contributed to research in topics: Visual word form area & Anatomy. The author has an hindex of 2, co-authored 3 publications receiving 26 citations. Previous affiliations of Sandrine Cremona include Centre national de la recherche scientifique.

Neuroimaging supports the representational nature of the earliest human engravings

Abstract: The earliest human graphic productions, consisting of abstract patterns engraved on a variety of media, date to the Lower and Middle Palaeolithic. They are associated with anatomically modern and archaic hominins. The nature and significance of these engravings are still under question. To address this issue, we used functional magnetic resonance imaging to compare brain activations triggered by the perception of engraved patterns dating between 540 000 and 30 000 years before the present with those elicited by the perception of scenes, objects, symbol-like characters and written words. The perception of the engravings bilaterally activated regions along the ventral route in a pattern similar to that activated by the perception of objects, suggesting that these graphic productions are processed as organized visual representations in the brain. Moreover, the perception of the engravings led to a leftward activation of the visual word form area. These results support the hypothesis that these engravings have the visual properties of meaningful representations in present-day humans, and could have served such purpose in early modern humans and archaic hominins.

Neuroimaging supports the representational nature of the earliest human engravings

Abstract: The earliest human graphic productions dating to the Lower and Middle Palaeolithic are associated with anatomically modern and archaic hominins. These productions, which consist of abstract patterns engraved on a variety of media, may have been used as symbols, and their emergence is thought to be associated with the evolution of the properties of the visual cortex. To test this hypothesis, we used functional magnetic resonance imaging to compare brain activations triggered by the perception of engraved patterns dating between 540,000 and 30,000 years before the present with those elicited by the perception of scenes, objects, symbol-like characters, and written words. The perception of the engravings bilaterally activated regions in the ventral route in a pattern similar to that produced by the perception of objects, suggesting that these graphic productions are processed as organized visual representations in the brain. Moreover, the perception of the engravings led to a leftward activation of the visual word form area. These results support the hypothesis that in contrast to random doodles, the earliest abstract graphic productions had a representational purpose for modern and archaic hominins.

The structural connectivity of the human angular gyrus as revealed by microdissection and diffusion tractography

Abstract: The angular gyrus (AG) has been described in numerous studies to be consistently activated in various functional tasks. The angular gyrus is a critical connector epicenter linking multiple functional networks due to its location in the posterior part of the inferior parietal cortex, namely at the junction between the parietal, temporal, and occipital lobes. It is thus crucial to identify the different pathways that anatomically connect this high-order association region to the rest of the brain. Our study revisits the three-dimensional architecture of the structural AG connectivity by combining state-of-the-art postmortem blunt microdissection with advanced in vivo diffusion tractography to comprehensively describe the association, projection, and commissural fibers that connect the human angular gyrus. AG appears as a posterior "angular stone" of associative connections belonging to mid- and long-range dorsal and ventral fibers of the superior and inferior longitudinal systems, respectively, to short-range parietal, occipital, and temporal fibers, including U-shaped fibers in the posterior transverse system. Thus, AG is at a pivotal dorso-ventral position reflecting its critical role in the different functional networks, particularly in language elaboration and spatial attention and awareness in the left and right hemispheres, respectively. We also reveal striatal, thalamic, and brainstem connections and a typical inter-hemispheric homotopic callosal connectivity supporting the suggested AG role in the integration of sensory input for modulating motor control and planning. The present description of AG's highly distributed wiring diagram may drastically improve intraoperative subcortical testing and post-operative neurologic outcomes related to surgery in and around the angular gyrus.

Novel characterization of the relationship between verbal list-learning outcomes and hippocampal subfields in healthy adults.

Abstract: The relationship between hippocampal subfield volumetry and verbal list-learning test outcomes have mostly been studied in clinical and elderly populations, and remain controversial. For the first time, we characterized a relationship between verbal list-learning test outcomes and hippocampal subfield volumetry on two large separate datasets of 447 and 1,442 healthy young and middle-aged adults, and explored the processes that could explain this relationship. We observed a replicable positive linear correlation between verbal list-learning test free recall scores and CA1 volume, specific to verbal list learning as demonstrated by the hippocampal subfield volumetry independence from verbal intelligence. Learning meaningless items was also positively correlated with CA1 volume, pointing to the role of the test design rather than word meaning. Accordingly, we found that association-based mnemonics mediated the relationship between verbal list-learning test outcomes and CA1 volume. This mediation suggests that integrating items into associative representations during verbal list-learning tests explains CA1 volume variations: this new explanation is consistent with the associative functions of the human CA1.

Cluster-based characterization of consistencies in individuals' thought profiles at rest in a cohort of 1779 French university students

Abstract: Abstract Is ongoing conscious thought spontaneous and situation-related, or is it recurrent and dependent on psychological dispositions? The answer is critical for resting-state functional connectivity (RSFC) paradigms that seek to correlate neuroanatomical states with conscious mental states. The goal of the present study was to characterize individual resting state thought profiles (RSTPs) and identify the recurrent ones, i.e., that could both be predicted by personality traits and predict subsequent negative affective states. The 1779 participants had a mean age of 22.1 years, 71.8% were females, and 71.8% were undergraduates. We collected the form and content of their thoughts during a 15-min RSFC session with a computerized retrospective self-questionnaire (ReSQ 2.0). Subsamples of participants also completed online autoquestionnaires assessing their psychological maturity and trait negative affectivity (with a four-day gap on average, N = 1270) and subsequent depressive and anxious states (1.4 years later on average, N = 922). Based on the multiple correspondence and clustering analyses of the ReSQ 2.0 responses, we identified six RSTPs distinctive by their content scope, temporal orientation, empathetic concern, and emotional valence. Multivariate analyses revealed that the probability of experiencing five of the six RSTPs was predicted by trait negative affectivity interacting with psychological maturity. Among them, a negatively valenced RSTP also increased the likelihood of subsequent negative affective states, suggesting its stable and recurrent nature. Identifying recurrent RSTPs is helpful for the future understanding of RSTPs’ contribution to RSFC. Additionally, it will be relevant to test whether acting on psychological maturity can alter the relationship between ongoing conscious thought and negative affectivity.

Object-related activity revealed byfunctional magnetic resonance imaging inhumanoccipital cortex

Abstract: Thestages ofintegration leading fromlocal feature analysis toobject recognition wereexplored inhuman visual cortex byusing thetechnique offunctional magnetic resonance imaging. Herewereport evidence forobject-related activation. Suchactivation waslocated atthelateral-posterior aspect oftheoccipital lobe, just abutting theposterior aspect ofthemotion-sensitive areaMT/V5,inaregion termed the lateral occipital complex (LO). LOshowedpreferential acti- vation toimages ofobjects, compared toawiderangeof texture patterns. Thisactivation wasnotcaused byaglobal difference intheFourier spatial frequency content ofobjects versus texture images, since object images produced enhanced LOactivation compared totextures matched inpowerspectra butrandomized inphase. Thepreferential activation toob- jects alsocould notbeexplained bydifferent patterns ofeye movements: similar levels ofactivation wereobserved when subjects fixated ontheobjects andwhentheyscanned the objects withtheir eyes. Additional manipulations suchas spatial frequency filtering anda4-fold change invisual size didnotaffect LO activation. Theseresults' suggest thatthe enhanced responses toobjects werenotamanifestation of low-level visual processing. A striking demonstration that activity inLOisuniquely correlated toobject detectability was produced bythe"Lincoln" illusion, inwhichblurring of objects digitized intolarge blocks paradoxically increases their recognizability. Suchblurring ledtosignificant en- hancement ofLOactivation. Despite thepreferential activa- tion toobjects, LO didnotseemtobeinvolved inthefinal, "semantic," stages oftherecognition process. Thus,objects varying widely intheir recognizability (e.g., famous faces, commonobjects, andunfamiliar three-dimensional abstract sculptures) activated ittoasimilar degree. Theseresults are thusevidence foranintermediate linkinthechainofpro- cessing stages leading toobject recognition inhumanvisual cortex.

A SENtence Supramodal Areas AtlaS (SENSAAS) based on multiple task-induced activation mapping and graph analysis of intrinsic connectivity in 144 healthy right-handers.

Abstract: We herein propose an atlas of 32 sentence-related areas based on a 3-step method combining the analysis of activation and asymmetry during multiple language tasks with hierarchical clustering of resting-state connectivity and graph analyses. 144 healthy right-handers performed fMRI runs based on language production, reading and listening, both with sentences and lists of over-learned words. Sentence minus word-list BOLD contrast and left-minus-right BOLD asymmetry for each task were computed in pairs of homotopic regions of interest (hROIs) from the AICHA atlas. Thirty-two hROIs were identified that were conjointly activated and leftward asymmetrical in each of the three language contrasts. Analysis of resting-state temporal correlations of BOLD variations between these 32 hROIs allowed the segregation of a core network, SENT_CORE including 18 hROIs. Resting-state graph analysis applied to SENT_CORE hROIs revealed that the pars triangularis of the inferior frontal gyrus and the superior temporal sulcus were hubs based on their degree centrality (DC), betweenness, and participation values corresponding to epicentres of sentence processing. Positive correlations between DC and BOLD activation values for SENT_CORE hROIs were observed across individuals and across regions regardless of the task: the more a SENT_CORE area is connected at rest the stronger it is activated during sentence processing. DC measurements in SENT_CORE may thus be a valuable index for the evaluation of inter-individual variations in language areas functional activity in relation to anatomical or clinical patterns in large populations. SENSAAS (SENtence Supramodal Areas AtlaS), comprising the 32 supramodal sentence areas, including SENT_CORE network, can be downloaded at http://www.gin.cnrs.fr/en/tools/.

Neuroimaging supports the representational nature of the earliest human engravings

Abstract: The earliest human graphic productions, consisting of abstract patterns engraved on a variety of media, date to the Lower and Middle Palaeolithic. They are associated with anatomically modern and archaic hominins. The nature and significance of these engravings are still under question. To address this issue, we used functional magnetic resonance imaging to compare brain activations triggered by the perception of engraved patterns dating between 540 000 and 30 000 years before the present with those elicited by the perception of scenes, objects, symbol-like characters and written words. The perception of the engravings bilaterally activated regions along the ventral route in a pattern similar to that activated by the perception of objects, suggesting that these graphic productions are processed as organized visual representations in the brain. Moreover, the perception of the engravings led to a leftward activation of the visual word form area. These results support the hypothesis that these engravings have the visual properties of meaningful representations in present-day humans, and could have served such purpose in early modern humans and archaic hominins.

Portable art from Pleistocene Sulawesi.

Abstract: The ability to produce recognizable depictions of objects from the natural world—known as figurative art—is unique to Homo sapiens and may be one of the cognitive traits that separates our species from extinct hominin relatives. Surviving examples of Pleistocene figurative art are generally confined to rock art or portable three-dimensional works (such as figurines) and images engraved into the surfaces of small mobile objects. These portable communicative technologies first appear in Europe some 40 thousand years ago (ka) with the arrival of H. sapiens. Conversely, despite H. sapiens having moved into Southeast Asia–Australasia by at least 65 ka, very little evidence for Pleistocene-aged portable art has been identified, leading to uncertainties regarding the cultural behaviour of the earliest H. sapiens in this region. Here, we report the discovery of two small stone ‘plaquettes’ incised with figurative imagery dating to 26–14 ka from Leang Bulu Bettue, Sulawesi. These new findings, together with the recent discovery of rock art dating to at least 40 ka in this same region, overturns the long-held belief that the first H. sapiens of Southeast Asia–Australasia did not create sophisticated art and further cements the importance of this behaviour for our species’ ability to overcome environmental and social challenges. Small, portable artworks have been missing from the archaeological record of the earliest Homo sapiens of Southeast Asia–Australasia. New excavations in Sulawesi have uncovered stone engravings of the natural world dating back to 26–14 ka.

A SENtence Supramodal Areas AtlaS (SENSAAS) based on multiple task-induced activation mapping and graph analysis of intrinsic connectivity in 144 healthy right-handers

Abstract: We herein propose an atlas of 32 sentence-related areas based on a 3-step method combining the analysis of activation and asymmetry during multiple language tasks with hierarchical clustering of resting-state connectivity and graph analyses. 144 healthy right-handers performed fMRI runs based on language production, reading and listening, both with sentences and lists of over-learned words. Sentence minus word- list BOLD contrast and left-minus-right BOLD asymmetry for each task were computed in pairs of homotopic regions of interest (hROIs) from the AICHA atlas. Thirty-two hROIs were identified that were conjointly activated and leftward asymmetrical in each of the 3 language contrasts. Analysis of resting-state temporal correlations of BOLD variations between these 32 hROIs allowed the segregation of a core network, SENT_CORE including 18 hROIs. Resting-state graph analysis applied to SENT_CORE hROIs revealed that the pars triangularis of the inferior frontal gyrus and the superior temporal sulcus were hubs based on their degree centrality, betweenness, and participation values, corresponding to epicentres of sentence processing. Positive correlations between DC and BOLD activation values for SENT_CORE hROIs were observed across individuals and across regions regardless of the task: the more a SENT_CORE area is connected at rest the stronger it is activated during sentence processing. DC measurements in SENT_CORE may thus be a valuable index for the evaluation of inter-individual variations in language areas functional activity in relation to anatomical or clinical patterns in large populations. SENSAAS (SENtence Supramodal Areas AtlaS), comprising the 32 supramodal sentence areas, including SENT-CORE network, can be downloaded at http://www.gin.cnrs.fr/en/tools/.