- Email: [email protected]
P8-21 Conflict processing of incongruent prosodic and semantic information
S152
Posters
repetitively measure prefrontal hemodynamic changes, and may be the useful tools for detecting the clinical staging of individuals suffering from symptoms. P8-20 Probabilistic spatial registration of NIRS imaging data with crossmodal clinical perspective 1
1
2
3
3
I. Dan , M. Okamoto , H. Dan , E. Lkhamsuren , D. Tsuzuki , E. Watanabe2 1 Center for Development of Advanced Medical Technology, Jichi Medical University, Tochigi, Japan, 2 Department of Neurosurgery, Jichi Medical University, Tochigi, Japan, 3 Graduate School of Systems and Information Engineering, University of Tsukuba, Ibaraki, Japan The recent advent of functional near-infrared spectroscopic imaging (NIRS) has expanded its technical potential for clinical diagnosis and neuropsychological research. NIRS utilizes the tight coupling between neural activity and regional cerebral blood flow, and monitors regional cerebral blood volume changes as relative changes of hemoglobin concentration. NIRS requires only compact experimental systems, is less restrictive, and thus provides researchers with a wide variety of flexible experimental setups. However, NIRS measurement has a technical drawback in that it measures cortical activities from the head surface without anatomical information of the object to be measured. We aimed to overcome this drawback by creating a link between stereotaxic coordinates such as Montreal Neurological Institute (MNI) standard brain coordinates and head-surface-based positioning systems such as the international 10 20 system. In other words, we tried to solve the NIRS spatial problem by registering NIRS data onto the MNI space via the international 10 20 system in a probabilistic manner. The current method allows the presentation of multi-subject or single-subject NIRS data in the MNI space with clear description of the associated positional variability. The standard deviation in probabilistic registration thus performed for given head surface points is approximately within the range of several millimeters. This means that if the spatial registration error is within an acceptable tolerance limit, it is possible to perform multi-subject NIRS analysis to make inference at the population level and to provide information on positional variability in the population, even when MRIs of subjects are not available. Such data presentation on a common platform can facilitate both intra- and inter-modal data sharing among the neuroimaging community. P8-21 Conflict processing of incongruent prosodic and semantic information M. Wittfoth1 , R. Dengler1 , S.A. Kotz2 Department of Neurology, Hannover Medical School, Hannover, Germany, 2 Max Planck Institute for Human Cognitive and Brain Sciences Stephanstrasse 1A, 04103 Leipzig, Germany
1
Objective: The modulation of voice intonation is an instrument to express the emotional stance in social interactions. The network associated with prosody processing is comprised of bilateral inferior frontal and posterior superior temporal gyrus/sulcus (pSTG/STS), and is most commonly implied in situations where prosody either matches the semantic content of the spoken sentence or where prosody is the only intelligible information (Schirmer et al., 2006; Wildgruber et al., 2006). In order to study the conflict induced by sentences with emotional prosody but with an incongruent semantic content, functional MRI data were acquired on a 3T scanner. Methods: Twenty subjects (10 females; age ranged from 22 35 years [mean age 24.9; SD = 3.7]) had to identify the emotional semantic content of spoken sentences (angry, happy, and neutral). Some of these sentences had a semantic content that did not match (e.g. a sentence spoken in an angry tone but with positive semantic content). Thus, we had two congruent, and two incongruent conditions. FMRI on a 3-T Siemens Trio scanner; data analysis with SPM5. Results: Valence-specific brain activity was found in the bilateral inferior frontal cortex. These clusters were specifically related to the processing of positive emotional prosody with interfering negative semantic content. Activation specifically related to the processing of angry emotional prosody with interfering positive semantic content were found in bilateral caudate nuclei. Conclusion: This study provides valence-related effects in the context of emotional conflict processing, as we found specific conflict-related networks for the processing of happy and angry intonations. The
caudate nucleus seems to play a major role in detecting angry prosodic information. Our results are an extension of previous findings (Wittfoth et al., 2010), and are corroborated by a recent study investigating prosodic processing in early human development (Grossmann et al., 2010). P8-22 Single trial classification of phonemes for electrocorticographic brain-machine interfaces T. Goto1,2 , M. Hirata1,2 , T. Yanagisawa1 , K. Matushita1 , M. Shayne1 , H. Sugata2 , Y. Saitoh1 , H. Kishima1 , S. Yorifuji2 , T. Yoshimine1 1 Department of Neurosurgery, Osaka University Medical School, Osaka, Japan, 2 Division of Functional Diagnostic Science, Osaka University Medical School, Osaka, Japan Objective: Since the activated brain regions in language process are broad and include common responses, it is difficult to find robust features for single trial classification. The aim of this study is to confirm the feasibility of a method for single trial classification of phonemes for an electrocorticographic brain-machine interface. Methods: We obtained electrocorticogram in five patients with brain tumor, intractable epilepsy, or intractable pain, who were implanted with subdural electrodes on areas over the inferior part of precentral gyrus (IPrG) and/or the inferior frontal gyrus (IFG) due to the need for treatment. The subjects pronounced either five (n = 4) or nine phonemes (n = 1). In case of five phonemes, the subjects voluntarily pronounced five Japanese vowels (a, i, u, e, o) repeatedly with an interval of more than 3 sec, and the trial was terminated when the least pronounced vowel was repeated twenty five times. The pronounced phonemes were inferred from the potentials or power changes in frequency bands by a support vector machine. We used a sliding period of interest in steps of 50 ms. Decoding accuracies were calculated in each period of interest and were also calculated for arbitrary selections of three phonemes. Results: The average of the best accuracy rate in each subject was 54.2% (S.D. 8.42) for 3 phonemes, 28.0% (S.D. 1.56) for 5 phonemes, and 18.6% for 9 phonemes. Accuracy increases before pronunciation and peaks in the periods of interest including both before and after pronunciation. The electrodes of high contribution for decoding were shown to be those at the IPrG and also the IFG. Conclusions: We examined the feasibility of single trial classification of phonemes for an electrocorticographic brain-machine interface. Our findings may also contribute to clarifying neural processes of pronouncing phonemes. P8-23 How Aristotelian categorical proposition structures could help to identify the neural basis of contradictory judgments M.T. Medaglia1,2 , F. Tecchio3,5 , L. Tomasevic3 , S. Seri2 , P.M. Rossini4,5 , C. Porcaro1 1 School of Psychology, University of Birmingham, Birmingham, UK, 2 Aston Brain Centre, School of Life and Health Sciences, Aston University, Birmingham, UK, 3 ISTC-CNR, Ospedale Fatebenefratelli, Isola Tiberina, Rome, Italy, 4 Dept. of Neurology, ‘Campus Bio-Medico’ University, Rome, Italy, 5 IRCCS San Raffaele, Tosinvest Sanita’, Cassino, Italy Objective: The identification of contradiction plays an important role in communication understanding and learning. To refute the statement ‘All man is tall’ it is sufficient to state ‘Some men are short’. We used typical forms within the Aristotelian categorical proposition structure to investigate whether identification of contradiction corresponded to different activation dynamics for the universal (‘All’) as opposed to the particular (‘Some’) operator and vice versa. Methods: Eight volunteer took part in this EEG experiment. The protocol contained 200 pairs of sentences, evenly divided in four forms. In the All Some Contradictory (AS-C) and All Some Not Contradictory (ASNC) the premise is universal (A: All) and the conclusion is particular (S: Some), whilst the conclusion is contradictory for the first set (AS-C) and not contradictory for the other set (AS-NC). Similarly for the SA-C and SA-NC. All sentences were randomly presented. A semiautomatic Independent Component Analysis (ICA)-based procedure was applied to eliminate artifactual activities. Results: Volunteer performed the SA and AS tasks with comparable accuracy, both for the contradictory and not contradictory conditions. On the contrary, reaction times showed a strong main Logical Operator
Posters
repetitively measure prefrontal hemodynamic changes, and may be the useful tools for detecting the clinical staging of individuals suffering from symptoms. P8-20 Probabilistic spatial registration of NIRS imaging data with crossmodal clinical perspective 1
1
2
3
3
I. Dan , M. Okamoto , H. Dan , E. Lkhamsuren , D. Tsuzuki , E. Watanabe2 1 Center for Development of Advanced Medical Technology, Jichi Medical University, Tochigi, Japan, 2 Department of Neurosurgery, Jichi Medical University, Tochigi, Japan, 3 Graduate School of Systems and Information Engineering, University of Tsukuba, Ibaraki, Japan The recent advent of functional near-infrared spectroscopic imaging (NIRS) has expanded its technical potential for clinical diagnosis and neuropsychological research. NIRS utilizes the tight coupling between neural activity and regional cerebral blood flow, and monitors regional cerebral blood volume changes as relative changes of hemoglobin concentration. NIRS requires only compact experimental systems, is less restrictive, and thus provides researchers with a wide variety of flexible experimental setups. However, NIRS measurement has a technical drawback in that it measures cortical activities from the head surface without anatomical information of the object to be measured. We aimed to overcome this drawback by creating a link between stereotaxic coordinates such as Montreal Neurological Institute (MNI) standard brain coordinates and head-surface-based positioning systems such as the international 10 20 system. In other words, we tried to solve the NIRS spatial problem by registering NIRS data onto the MNI space via the international 10 20 system in a probabilistic manner. The current method allows the presentation of multi-subject or single-subject NIRS data in the MNI space with clear description of the associated positional variability. The standard deviation in probabilistic registration thus performed for given head surface points is approximately within the range of several millimeters. This means that if the spatial registration error is within an acceptable tolerance limit, it is possible to perform multi-subject NIRS analysis to make inference at the population level and to provide information on positional variability in the population, even when MRIs of subjects are not available. Such data presentation on a common platform can facilitate both intra- and inter-modal data sharing among the neuroimaging community. P8-21 Conflict processing of incongruent prosodic and semantic information M. Wittfoth1 , R. Dengler1 , S.A. Kotz2 Department of Neurology, Hannover Medical School, Hannover, Germany, 2 Max Planck Institute for Human Cognitive and Brain Sciences Stephanstrasse 1A, 04103 Leipzig, Germany
1
Objective: The modulation of voice intonation is an instrument to express the emotional stance in social interactions. The network associated with prosody processing is comprised of bilateral inferior frontal and posterior superior temporal gyrus/sulcus (pSTG/STS), and is most commonly implied in situations where prosody either matches the semantic content of the spoken sentence or where prosody is the only intelligible information (Schirmer et al., 2006; Wildgruber et al., 2006). In order to study the conflict induced by sentences with emotional prosody but with an incongruent semantic content, functional MRI data were acquired on a 3T scanner. Methods: Twenty subjects (10 females; age ranged from 22 35 years [mean age 24.9; SD = 3.7]) had to identify the emotional semantic content of spoken sentences (angry, happy, and neutral). Some of these sentences had a semantic content that did not match (e.g. a sentence spoken in an angry tone but with positive semantic content). Thus, we had two congruent, and two incongruent conditions. FMRI on a 3-T Siemens Trio scanner; data analysis with SPM5. Results: Valence-specific brain activity was found in the bilateral inferior frontal cortex. These clusters were specifically related to the processing of positive emotional prosody with interfering negative semantic content. Activation specifically related to the processing of angry emotional prosody with interfering positive semantic content were found in bilateral caudate nuclei. Conclusion: This study provides valence-related effects in the context of emotional conflict processing, as we found specific conflict-related networks for the processing of happy and angry intonations. The
caudate nucleus seems to play a major role in detecting angry prosodic information. Our results are an extension of previous findings (Wittfoth et al., 2010), and are corroborated by a recent study investigating prosodic processing in early human development (Grossmann et al., 2010). P8-22 Single trial classification of phonemes for electrocorticographic brain-machine interfaces T. Goto1,2 , M. Hirata1,2 , T. Yanagisawa1 , K. Matushita1 , M. Shayne1 , H. Sugata2 , Y. Saitoh1 , H. Kishima1 , S. Yorifuji2 , T. Yoshimine1 1 Department of Neurosurgery, Osaka University Medical School, Osaka, Japan, 2 Division of Functional Diagnostic Science, Osaka University Medical School, Osaka, Japan Objective: Since the activated brain regions in language process are broad and include common responses, it is difficult to find robust features for single trial classification. The aim of this study is to confirm the feasibility of a method for single trial classification of phonemes for an electrocorticographic brain-machine interface. Methods: We obtained electrocorticogram in five patients with brain tumor, intractable epilepsy, or intractable pain, who were implanted with subdural electrodes on areas over the inferior part of precentral gyrus (IPrG) and/or the inferior frontal gyrus (IFG) due to the need for treatment. The subjects pronounced either five (n = 4) or nine phonemes (n = 1). In case of five phonemes, the subjects voluntarily pronounced five Japanese vowels (a, i, u, e, o) repeatedly with an interval of more than 3 sec, and the trial was terminated when the least pronounced vowel was repeated twenty five times. The pronounced phonemes were inferred from the potentials or power changes in frequency bands by a support vector machine. We used a sliding period of interest in steps of 50 ms. Decoding accuracies were calculated in each period of interest and were also calculated for arbitrary selections of three phonemes. Results: The average of the best accuracy rate in each subject was 54.2% (S.D. 8.42) for 3 phonemes, 28.0% (S.D. 1.56) for 5 phonemes, and 18.6% for 9 phonemes. Accuracy increases before pronunciation and peaks in the periods of interest including both before and after pronunciation. The electrodes of high contribution for decoding were shown to be those at the IPrG and also the IFG. Conclusions: We examined the feasibility of single trial classification of phonemes for an electrocorticographic brain-machine interface. Our findings may also contribute to clarifying neural processes of pronouncing phonemes. P8-23 How Aristotelian categorical proposition structures could help to identify the neural basis of contradictory judgments M.T. Medaglia1,2 , F. Tecchio3,5 , L. Tomasevic3 , S. Seri2 , P.M. Rossini4,5 , C. Porcaro1 1 School of Psychology, University of Birmingham, Birmingham, UK, 2 Aston Brain Centre, School of Life and Health Sciences, Aston University, Birmingham, UK, 3 ISTC-CNR, Ospedale Fatebenefratelli, Isola Tiberina, Rome, Italy, 4 Dept. of Neurology, ‘Campus Bio-Medico’ University, Rome, Italy, 5 IRCCS San Raffaele, Tosinvest Sanita’, Cassino, Italy Objective: The identification of contradiction plays an important role in communication understanding and learning. To refute the statement ‘All man is tall’ it is sufficient to state ‘Some men are short’. We used typical forms within the Aristotelian categorical proposition structure to investigate whether identification of contradiction corresponded to different activation dynamics for the universal (‘All’) as opposed to the particular (‘Some’) operator and vice versa. Methods: Eight volunteer took part in this EEG experiment. The protocol contained 200 pairs of sentences, evenly divided in four forms. In the All Some Contradictory (AS-C) and All Some Not Contradictory (ASNC) the premise is universal (A: All) and the conclusion is particular (S: Some), whilst the conclusion is contradictory for the first set (AS-C) and not contradictory for the other set (AS-NC). Similarly for the SA-C and SA-NC. All sentences were randomly presented. A semiautomatic Independent Component Analysis (ICA)-based procedure was applied to eliminate artifactual activities. Results: Volunteer performed the SA and AS tasks with comparable accuracy, both for the contradictory and not contradictory conditions. On the contrary, reaction times showed a strong main Logical Operator