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Grandjean, D.

Publications and source records attributed to Grandjean, D..

31 records · Page 2Linked to original sources

Social Context and Drug Cues Modulate Inhibitory Control in Cocaine Addiction: involvement of the STN evidenced through Functional Magnetic Resonance Imaging

BackgroundAddictions often develop in a social context, although the influence of social factors did not receive much attention in the neuroscience of addiction. Recent animal studies suggest that peer presence can reduce cocaine intake, an influence potentially mediated, among others, by the subthalamic nucleus (STN). However, there is to date no such neurobiological study in humans. MethodsThis study investigated the impact of social context and drug cues on brain correlates of inhibitory control in individuals with and without cocaine use disorder (CUD) using functional Magnetic Resonance Imaging (fMRI). Seventeen CUD participants and 17 healthy controls (HC) performed a novel fMRI Stop-Signal task in the presence and absence of an observer while being exposed to cocaine-related and neutral pictures as cues. ResultsThe results showed that CUD participants, while slower at stopping with neutral cues, recovered control level stopping abilities with cocaine cues, while HC did not show any difference. Neuroimaging revealed the involvement of frontal cortical regions and of the subthalamic nucleus (STN) in inhibitory control, which was modulated by both social context and drug cues in CUD participants but not in HC. ConclusionsThese findings highlight the impact of social context and drug cues on inhibitory control in CUD and suggest potential targets for intervention such as the STN, also emphasizing the importance of considering the social context in addiction research and treatment.

neuroscience↗

Model-based frontal cortex analysis reveals origins of human non-verbal communication

The ability to process verbal language seems unique to humans and relies not only on semantics but on other forms of communication such as affective vocalisations, that we share with other primate species--particularly great apes (Hominidae). To better understand these processes at the behavioural and brain level, we asked human participants to categorize vocalizations of four primate species including human, great apes (chimpanzee and bonobo), and monkey (rhesus macaque) during MRI acquisition. Classification was above chance level for all species but bonobo vocalizations. Imaging analyses were computed using a participant-specific, trial-by-trial fitted probability categorization value in a model-based style of data analysis. Model-based analyses revealed the implication of the bilateral orbitofrontal cortex and inferior frontal gyrus pars triangularis (IFGtri) respectively correlating and anti-correlating with the fitted probability of accurate species classification. Further conjunction analyses revealed enhanced activity in a sub-area of the left IFGtri specifically for the accurate classification of chimpanzee calls compared to human voices. Our data therefore reveal distinct frontal mechanisms that shed light on how the human brain evolved to process non-verbal language. Author contributionsCD and LC were involved in every steps of the study including experimental design, programming, data acquisition, data analysis and redaction of the first draft of the manuscript and subsequent editing. EP helped design the model-based MRI analyses and interpret the results. TG and DG were involved in the experimental design and study planification. All authors wrote and edited the manuscript.

neuroscience↗

Preterm infants voice processing is mediated by voice familiarity

To understand the consequences of prematurity on language perception it is fundamental to determine how atypical early sensory experience affects brain development. To date the neural oscillatory correlates in the time-frequency domain of voice processing as a function of atypical early sensory experience, as after premature birth, remain elusive. At term equivalent age, ten preterm and ten full-term newborns underwent high-density EEG recordings during mother or stranger speech presentation, presented in the forward (naturalistic) or backward order. A general group effect terms > preterms for the naturalistic mothers voice is evident in the theta frequency band in the left temporal area, where only full-term newborns showed an increased activity for the mothers voice, whereas preterm infants showed significant activation for stranger naturalistic speech. Similarly, a significant group contrast in the low and high theta in the right temporal regions indicates higher activations for the strangers speech in preterms. Finally, only full-term newborns presented a late gamma band increase for the maternal naturalistic speech, indicating a more mature brain response. The current study based on neural time-frequency patterns, demonstrates that preterm infants lack selective brain responses to mothers naturalistic voice typical for full-term newborns, whereas preterms are selectively responsive to stranger voices in both temporal hemispheres.

neuroscience↗

Cerebral activity in monkeys Papio anubis during the perception of conspecific and heterospecific agonistic vocalizations: A functional Near Infrared Spectroscopy study

Are conspecific emotional vocalizations special? Although often investigated in non-human primates using functional magnetic resonance imaging or positron emission tomography, it remains unclear whether the listening of conspecific vocal emotions leads to similar or different cerebral activations when compared to heterospecific calls (i.e. expressed by another primate species). Using a neuroimaging technique rarely employed in monkeys so far, functional Near Infrared Spectroscopy (fNIRS), the present study investigated cortical temporal activities during exposure to both conspecific and heterospecific calls in three female adult baboons (Papio anubis). The three subjects were lightly anesthetized and passively exposed to agonistic baboon and chimpanzee (Pan troglodytes) vocalizations, as well as energy matched white noises in order to control for this low-level acoustic feature. Despite inter-individual variabilities, permutation test analyses on the extracted OxyHemoglobin signal revealed for two subjects out of three significant differences between the passive listening of baboon versus chimpanzee stimuli. Additionally, in one subject, a modulation of the left temporal cortex activity was found for the perception of baboon calls contrasted to chimpanzee vocalizations as well as for the passive listening of baboon white noises compared to chimpanzee ones. Although the lack of generalization of those findings in all three subjects prevents us to drawn any conclusion and that more subjects would be needed, the hypothesis that baboons cortical temporal regions may be more sensitive to the processing of conspecific sounds compared to heterospecific stimuli is not excluded. Our study highlights that fNIRS may be a promising alternative to further investigate the auditory mechanisms at play in the right and left baboons temporal cortices for the processing of emotional vocalizations.

neuroscience↗

Categorization and discrimination of human and non-human primate affective vocalizations: investigation of the frontal cortex activity through fNIRS.

Many species, including humans and non-human primates, react differently to threatening or pleasant situations. Because of its adaptiveness, recognizing affective signals is likely to be reflected in a capability of modern humans to recognize other closely related species call content. However, at both behavioural and neural levels, only few studies have used a comparative approach to understand affective decoding processes in humans, particularly with respect to affective vocalizations. Previous research in neuroscience about the recognition of human affective vocalizations has shown the critical involvement of temporal and frontal regions. In particular, frontal regions have been reported as crucial in the explicit decoding of vocal emotions especially in different task complexity such as discrimination or categorization. The aim of this study using functional Near Infrared Spectroscopy (fNIRS) was to specifically investigate the neural activity of the inferior frontal cortex pars triangularis (IFGtri) and the prefrontal cortex (PFC) underlying categorization (A versus B) and discrimination (A versus non-A) mechanisms of positive and negative affects in human, great apes (chimpanzee and bonobo), and monkey (rhesus macaque) vocalizations. We also analysed participants behavioural responses and correlated them with the recorded frontal activations. While performing the tasks, fNIRS data revealed a clear distinction between the two frontal regions, with a general positive activation of IFGtri compared to a decrease of PFC activity. We also found a modulation of IFGtri and PFC activations depending on both the species considered and on task complexity; with generally more activity in the IFGtri during discrimination compared to categorization, and a more intense decrease of the PFC in categorization compared to discrimination. Behaviourally, participants recognized almost all affective cues in all species vocalizations at above chance levels in the discrimination task (except for threatening bonobo calls). For categorization, they mostly correctly identified at levels significantly above chance affective contents in human and great ape vocalizations but not in macaque calls. Overall, these findings support the hypothesis of a pre-human origin of affective recognition processing inherited from our common ancestor with other great apes and processed in the frontal cortex. Our results also highlight behavioural differences related to task complexity, i.e. between categorization and discrimination processes, and the differential involvement of the PFC and the IFGtri, which seems necessary to explicitly decode affects in all primate vocalizations.

neuroscience↗

Humans recognize affective cues in primate vocalizations: Acoustic and phylogenetic perspectives

Humans are adept in extracting affective information from the vocalisations of not only humans but also other animals. Current research has mainly focused on phylogenetic proximity to explain such cross-species emotion recognition abilities. However, because research protocols are inconsistent across studies, it remains unclear whether human recognition of vocal affective cues of other species is due to cross-taxa similarities between acoustic parameters, the phylogenetic distances between species, or a combination of both. To address this, we first analysed acoustic variation in 96 affective vocalizations, including agonistic and affiliative contexts, of humans and three other primate species - rhesus macaques, chimpanzees and bonobos - the latter two being equally phylogenetically distant from humans. Using Mahalanobis distances, we found that chimpanzee vocalizations were acoustically closer to those of humans than to those of bonobos, confirming a potential derived vocal evolution in the bonobo lineage. Second, we investigated whether 68 human participants recognized the affective basis of vocalisations through tasks by asking them to categorize ( A vs B) or discriminate ( A vs non-A) vocalisations based on their affective content. Results showed that participants could reliably categorize and discriminate most of the affective vocal cues expressed by other primates, except threat calls by bonobos and macaques. Overall, participants showed greatest accuracy in detecting chimpanzee vocalizations; but not bonobo vocalizations, which provides support for both the phylogenetic proximity and acoustic similarity hypotheses. Our results highlight for the first time the importance of both phylogenetic and acoustic parameter level explanations in cross-species affective perception, drawing a more complex picture to explain our natural understanding of animal signals.

animal behavior and cognition↗

Disrupting inferior frontal cortex activity alters affect decoding efficiency from clear but not from ambiguous affective speech

The evaluation of socio-affective sound information is accomplished by the primate auditory cortex in collaboration with limbic and inferior frontal cortex (IFC)--often observed during affective voice classification. Partly opposing views have been proposed, with IFC either coding cognitive processing challenges in case of sensory ambiguity or representing categorical object and affect information for clear voices. Here, we presented clear and ambiguous affective speech to two groups of human participants during neuroimaging, while in one group we inhibited right IFC activity with transcranial magnetic stimulation. IFC activity inhibition led to faster affective decisions, more accurate choice probabilities, reduced auditory cortical activity and increased fronto-limbic connectivity for clear affective speech. This indicates a more intermediate functional property of the IFC than assumed--namely with normal activity representing a more deliberate form of affective sound processing (i.e., enforcing cognitive analysis) that flags categorical sound decisions with precaution (i.e., representation of categorical uncertainty). TeaserInferior frontal cortex enforces cognitive analyses during affect decisions with different levels of sensory ambiguity.

neuroscience↗

Frontoparietal, cerebellum network codes for accurate intention prediction in altered perceptual conditions

Integrating and predicting intentions and actions of others are crucial components of social interactions, but the behavioral and neural underpinnings of such mechanisms in altered perceptual conditions remain poorly understood. We demonstrated that expertise was necessary to successfully understand and evaluate communicative intent in spatially and temporally altered visual representations of music plays, recruiting frontoparietal regions and several sub-areas of the cerebellum. Functional connectivity between these brain areas revealed widespread organization, especially in the cerebellum. This network may be essential to assess communicative intent in ambiguous or complex visual scenes.

neuroscience↗

Basal ganglia and cerebellar contributions to vocal emotion processing: a high resolution fMRI study

Until recently, brain networks underlying emotional voice prosody decoding and processing were focused on modulations in primary and secondary auditory, ventral frontal and prefrontal cortices, and the amygdala. Growing interest for a specific role of the basal ganglia and cerebellum was recently brought into the spotlight. In the present study, we aimed at characterizing the role of such subcortical brain regions in vocal emotion processing, at the level of both brain activation and functional and effective connectivity, using high resolution functional magnetic resonance imaging. Variance explained by low-level acoustic parameters (fundamental frequency, voice energy) was also modelled. Wholebrain data revealed expected contributions of the temporal and frontal cortices, basal ganglia and cerebellum to vocal emotion processing, while functional connectivity analyses highlighted correlations between basal ganglia and cerebellum, especially for angry voices. Seed-to-seed and seed-to-voxel effective connectivity revealed direct connections within the basal ganglia especially between the putamen and external globus pallidus and between the subthalamic nucleus and the cerebellum. Our results speak in favour of crucial contributions of the basal ganglia, especially the putamen, external globus pallidus and subthalamic nucleus, and several cerebellar lobules and nuclei for an efficient decoding of and response to vocal emotions.

neuroscience↗

Human temporal voice areas are sensitive to chimpanzee vocalizations

Withdrawal StatementThe authors have withdrawn this manuscript due to a duplicate posting of manuscript number BIORXIV/2025/677258. Therefore, the authors do not wish this work to be cited as reference for the project. If you have any questions, please contact the corresponding author. The correct preprint can be found at doi: 10.1101/2025.09.19.677258

neuroscience↗

Brain activation lateralization in monkeys (Papio Anubis) following asymmetric motor and auditory stimulations through functional Near Infrared Spectroscopy

Hemispheric asymmetries have long been seen as characterizing the human brain; yet, an increasing number of reports suggest the presence of such brain asymmetries in our closest primate relatives. However, most available data in non-human primates have so far been acquired as part of neurostructural approaches such as MRI, while comparative data in humans are often dynamically acquired as part of neurofunctional studies. In the present exploratory study in baboons (Papio Anubis), we tested whether brain lateralization could be recorded non-invasively using a functional Near-Infrared Spectroscopy (fNIRS) device in two contexts: motor and auditory passive stimulations. Under light propofol anaesthesia monitoring, three adult female baboons were exposed to a series of (1) left-versus right-arm passive movement stimulations; and (2) left-versus right-ear versus stereo auditory stimulations while recording fNIRS signals in the related brain areas (i.e., motor central sulcus and superior temporal cortices respectively). For the motor condition our results show that left-arm versus right-arm stimulations induced typical contralateral difference in hemispheric activation asymmetries in the three subjects for all three channels. For the auditory condition, we also revealed typical human-like patterns of hemispheric asymmetries in one subject for all three channels, namely (1) typical contralateral differences in hemispheric asymmetry between left-ear versus right-ear stimulations, and (2) a rightward asymmetry for stereo stimulations. Overall, our findings support the use of fNIRS to investigate brain processing in non-human primates from a functional perspective, opening the way for the development of non-invasive procedures in non-human primate brain research.

neuroscience↗

Detection dogs as a help in the detection of COVID-19: Can the dog alert on COVID-19 positive persons by sniffing axillary sweat samples? Proof-of-concept study

The aim of this study is to evaluate if the sweat produced by COVID-19 persons (SARS-CoV-2 PCR positive) has a different odour for trained detection dogs than the sweat produced by non COVID-19 persons. The study was conducted on 3 sites, following the same protocol procedures, and involved a total of 18 dogs. A total of 198 armpits sweat samples were obtained from different hospitals. For each involved dog, the acquisition of the specific odour of COVID-19 sweat samples required from one to four hours, with an amount of positive samples sniffing ranging from four to ten. For this proof of concept, we kept 8 dogs of the initial group (explosive detection dogs and colon cancer detection dogs), who performed a total of 368 trials, and will include the other dogs in our future studies as their adaptation to samples scenting takes more time.The percentages of success of the dogs to find the positive sample in a line containing several other negative samples or mocks (2 to 6) were 100p100 for 4 dogs, and respectively 83p100, 84p100, 90p100 and 94p100 for the others, all significantly different from the percentage of success that would be obtained by chance alone.We conclude that there is a very high evidence that the armpits sweat odour of COVID-19+ persons is different, and that dogs can detect a person infected by the SARS-CoV-2 virus.Competing Interest StatementThe authors have declared no competing interest.View Full Text

animal behavior and cognition↗

Human discrimination and categorization of emotions in voices: a functional Near-Infrared Spectroscopy (fNIRS) study

Variations of the vocal tone of the voice during speech production, known as prosody, provide information about the emotional state of the speaker. In recent years, functional imaging has suggested a role of both right and left inferior frontal cortices in attentive decoding and cognitive evaluation of emotional cues in human vocalizations. Here, we investigated the suitability of functional Near-Infrared Spectroscopy (fNIRS) to study frontal lateralization of human emotion vocalization processing during explicit and implicit categorization and discrimination. Participants listened to speech-like but semantically meaningless words spoken in a neutral, angry or fearful tone and had to categorize or discriminate them based on their emotional or linguistic content. Behaviorally, participants were faster to discriminate than to categorize and they processed the linguistic content of stimuli faster than their emotional content, while an interaction between condition (emotion/word) and task (discrimination/categorization) influenced accuracy. At the brain level, we found a four-way interaction in the fNIRS signal between condition, task, emotion and channel, highlighting the involvement of the right hemisphere to process fear stimuli, and of both hemispheres to treat anger stimuli. Our results show that fNIRS is suitable to study vocal emotion evaluation in humans, fostering its application to study emotional appraisal.

neuroscience↗