Changes In Hemodynamic Signals Research Articles

No observation of DIANA signals in rats at 7.0 and 17.2 Tesla

Abstract Recently, a new method was introduced to detect neuronal activity using MRI. The method, referred to as DIANA, showed MRI signals with millisecond temporal resolution that correlated with local field potentials measured invasively in mice. Troublingly, attempts by other groups to detect the DIANA signals in humans at 7 Tesla and mice at 15.2 Tesla have failed. So far, attempts to reproduce DIANA in small rodents have focused on paradigms using whisker pad stimulation, which were expected to produce a 0.1-0.15% signal change. However, the supplementary material accompanying the original DIANA paper showed that visual stimulation produced a three times larger signal, which should be much easier to detect. Therefore, we attempted to find the DIANA signal in rats using a visual stimulation paradigm. Experiments were performed at 17.2 Tesla but also at 7.0 Tesla to see if the DIANA signal appears at a lower field strength where T2 is longer and BOLD contributions are reduced. In addition, simulations were performed to investigate the theoretical detectability of synthetic DIANA signals in noisy data. Although our data indicated that a 0.1% signal change would have been detectable, we did not observe a DIANA signal. We did observe neuronally driven hemodynamic signal variations that were much larger than the anticipated DIANA signal. The amplitude of these signal changes was relatively similar at 7.0 and 17.2 Tesla (0.7% vs 1.1%). Numerical simulations indicated, however, that the measured hemodynamic signal changes would not interfere with the detection of DIANA signals. Therefore, it is reasonable to expect that measurements at higher field strength with improved SNR would have a better chance to detect the DIANA signal. Yet, we, among others, were unable to find it.

Hemodynamic signal changes during volitional swallowing in dysphagia patients with different unilateral hemispheric stroke and brainstem stroke: A near-infrared spectroscopy study

Background and objectivesStrokes will result in decreased in cortical excitability and changed in the balance between the affected and unaffected hemispheres. Previous studies have focused on cortical changes in healthy subjects during swallowing, while they remain unknown in patients with stroke at different locations. Thus, the purpose of this study was to research cortical activation patterns of swallowing in patients with dysphagia and healthy subjects by the functional near-infrared spectroscopy (fNIRS). We also focus on the comparability of brain activation areas associated with swallowing between patients with different stroke locations and healthy subjects. Methodstotal of 104 participants were invited to our study, involving 86 patients with dysphagic unilateral hemispheric stroke and 18 age and sex matched healthy controls. The stroke patients were categorized into patients with left unilateral stroke lesions (n = 30), patients with right unilateral stroke lesions (n = 32) and patients with brainstem injury (n = 24) according to different stroke sites. All patients underwent a series of clinical swallowing function assessments, such as the Fiberoptic endoscopic dysphagia severity scale (FEDSS), penetration-aspiration scale (PAS) of Rosenbek, the gugging swallowing screen (GUSS) and the functional oral Intake scale (FOIS) after informed consent has been signed. All participants received the fNIRS system assessment. ResultsThe results showed that extensive areas of the cerebral cortex activated during the swallowing tasks in healthy participants (P < FDR 0.05). For patients with left unilateral stroke lesions, the HbO concentration were strongest over the right hemisphere (P < FDR 0.05). In addition, a less severe activation was also observed in the left hemisphere. Comparable to patients with left unilateral stroke lesions, the strongest activation during swallowing task were found in the left hemisphere in patients with right unilateral stroke lesions (P < FDR 0.05). Similarly, the right hemisphere also has activated less. In contrast, patients with brain stem injury showed more bilaterally activation patterns. ConclusionOur finding states that cortical activation areas differ between patients with different stroke locations and healthy subjects during swallowing. There was a more bilateral activation in healthy participants and patients with lesions in the brainstem while more cortical activation in unaffected hemisphere in patients with unilateral hemispheric stroke. It also provides a basis for the future treatment of dysphagia after stroke.

Hemodynamic signal changes and functional connectivity in acute stroke patients with dysphagia during volitional swallowing: a pilot study.

Dysphagia is one of the major post-stroke complications, understanding post-stroke changes in cortical excitability and promoting early remodeling of swallowing-related cortical areas to enable accurate treatment is essential for recovery of patients. We aimed to investigate hemodynamic signal changes and functional connectivity in acute stroke patients with dysphagia compared to age-matched healthy participants in response to volitional swallowing using functional near-infrared spectroscopy (fNIRS) in this pilot study. Patients with first-ever post-stroke dysphagia having an onset of 1-4 weeks and age-matched right-handed healthy subjects were recruited in our study. fNIRS with 47 channels was utilized to detect the oxyhemoglobin (HbO2 ) and reduced hemoglobin (HbR) concentration changes when volitional swallowing. Cohort analysis was performed by a one-sample t-test. Two-sample t-test was utilized to compare the difference in cortical activation between patients with post-stroke dysphagia and healthy subjects. Furthermore, the relative changes in the concentration of the HbO2 throughout the experimental procedure were extracted for the functional connectivity analysis. The Pearson correlation coefficients of the HbO2 concentration of each channel were analyzed on a time series, and then a Fisher Z transformation was then performed, and the transformed values were defined as the functional connection strengths between the channels. In this present study, a total of nine patients with acute post-stroke dysphagia were enrolled in the patient group and nine age-matched healthy participants in the healthy control group. Our study observed that the extensive regions of the cerebral cortex were activated in the healthy control group, while the activation area of patient group's cortical regions was quite limited. The mean functional connectivity strength of participants was 0.485 ± 0.105 in the healthy control group, and 0.252 ± 0.146 in the patient group, with a significant difference between the two groups (p = 0.001). Compared to the healthy individuals, cerebral cortex regions of acute stroke patients were only marginally activated during volitional swallowing task, and the average functional connectivity strength of cortical network in patients was relatively weaker.

Hemodynamic signal changes and swallowing improvement of repetitive transcranial magnetic stimulation on stroke patients with dysphagia: A randomized controlled study.

ObjectiveOur study aims to measure the cortical correlates of swallowing execution in patients with dysphagia after repetitive transcranial magnetic stimulation (rTMS) therapy using functional near-infrared spectroscopy (fNIRS), and observe the change of pattern of brain activation in stroke patients with dysphagia after rTMS intervention. In addition, we tried to analyze the effect of rTMS on brain activation in dysphagia patients with different lesion sides. This study also concentrated on the effect of stimulating the affected mylohyoid cortical region by 5 Hz rTMS, providing clinical evidence for rTMS therapy of dysphagia in stroke patients.MethodsThis study was a sham-controlled, single-blind, randomized controlled study with a blinded observer. A total of 49 patients completed the study, which was randomized to the rTMS group (n = 23) and sham rTMS group (n = 26) by the random number table method. The rTMS group received 5 Hz rTMS stimulation to the affected mylohyoid cortical region of the brain and the sham rTMS group underwent rTMS using the same parameters as the rTMS group, except for the position of the coil. Each patient received 2 weeks of stimulation followed by conventional swallowing therapy. Standardized Swallowing Assessment (SSA), Fiberoptic Endoscopic Dysphagia Severity Scale (FEDSS), Penetration-Aspiration Scale (PAS), and functional oral intake status were assessed at two times: baseline (before treatment) and 2 weeks (after intervention). Meanwhile, we use the fNIRS system to measure the cerebral hemodynamic changes during the experimental procedure.ResultsThe rTMS group exhibited significant improvement in the SSA scale, FEDSS scale, and PAS scale after rTMS therapy (all P < 0.001). The sham rTMS group had the same analysis on the same scales (all P < 0.001). There was no significant difference observed in clinical assessments at 2 weeks after baseline between the rTMS group and sham rTMS group (all P > 0.05). However, there were statistically significant differences between the two groups in the rate of change in the FEDSS score (P = 0.018) and PAS score (P = 0.004), except for the SSA score (P = 0.067). As for the removal rate of the feeding tube, there was no significant difference between the rTMS group and sham rTMS group (P = 0.355), but there was a significant difference compared with the baseline characteristics in both groups (PrTMS < 0.001, PshamrTMS = 0.002). In fNIRS analysis, the block average result showed differences in brain areas RPFC (right prefrontal cortex) and RMC (right motor cortex) significantly between the rTMS group and sham rTMS group after intervention (Pchannel30 = 0.046, Pchannel16 = 0.006). In the subgroup analysis, rTMS group was divided into left-rTMS group and right-rTMS group and sham rTMS group was divided into sham left-rTMS group and sham right-rTMS group. The fNIRS results showed no significance in block average and block differential after intervention between the left-rTMS group and sham left-rTMS group, but differences were statistically significant between the right-rTMS group and sham right-rTMS group in block average: channel 30 (T = −2.34, P = 0.028) in LPFC (left prefrontal cortex) and 16 (T = 2.54, P = 0.018) in RMC. After intervention, there was no significance in left-rTMS group compared with baseline, but in right-rTMS group, channel 27 (T = 2.18, P = 0.039) in LPFC and 47 (T = 2.17, P = 0.039) in RPFC had significance in block differential. In the sham rTMS group, neither sham left-rTMS group and sham right-rTMS group had significant differences in block average and block differential in each brain area after intervention (P > 0.05).ConclusionsThe present study confirmed that a 5-Hz rTMS is feasible at the affected mylohyoid cortical region in post-stroke patients with dysphagia and rTMS therapy can alter cortical excitability. Based on previous studies, there is a dominant hemisphere in swallowing and the results of our fNIRS analysis seemed to show a better increase in cortical activation on the right side than on the left after rTMS of the affected mylohyoid cortical region. However, there was no difference between the left and right hemispheres in the subgroup analysis. Nevertheless, the present study provides a novel and feasible method of applying fNIRS to assessment in stroke patients with dysphagia.

Hemodynamic Signal Changes During Motor Imagery Task Performance Are Associated With the Degree of Motor Task Learning.

PurposeThis study aimed to investigate whether oxygenated hemoglobin (oxy-Hb) generated during a motor imagery (MI) task is associated with the motor learning level of the task.MethodsWe included 16 right-handed healthy participants who were trained to perform a ball rotation (BR) task. Hemodynamic brain activity was measured using near-infrared spectroscopy to monitor changes in oxy-Hb concentration during the BR MI task. The experimental protocol used a block design, and measurements were performed three times before and after the initial training of the BR task as well as after the final training. The BR count during training was also measured. Furthermore, subjective vividness of MI was evaluated three times after NIRS measurement using the Visual Analog Scale (VAS).ResultsThe results showed that the number of BRs increased significantly with training (P < 0.001). VAS scores also improved with training (P < 0.001). Furthermore, oxy-Hb concentration and the region of interest (ROI) showed a main effect (P = 0.001). An interaction was confirmed (P < 0.001), and it was ascertained that the change in oxy-Hb concentrations due to training was different for each ROI. The most significant predictor of subjective MI vividness was supplementary motor area (SMA) oxy-Hb concentration (coefficient = 0.365).DiscussionHemodynamic brain activity during MI tasks may be correlated with task motor learning levels, since significant changes in oxy-Hb concentrations were observed following initial and final training in the SMA. In particular, hemodynamic brain activity in the SMA was suggested to reflect the MI vividness of participants.

Hemodynamic signal changes during saliva and water swallowing: a near-infrared spectroscopy study.

Here, we compared the hemodynamic response observed during swallowing of water or saliva using near-infrared spectroscopy (NIRS). Sixteen healthy adults swallowed water or saliva in a randomized order. Relative concentration changes in oxygenated and deoxygenated hemoglobin during swallowing were assessed. Both swallowing tasks led to the strongest NIRS signal change over the bilateral inferior frontal gyrus. Water swallowing led to a stronger activation over the right hemisphere while the activation focus for saliva swallowing was stronger left lateralized. The NIRS time course also differed between both swallowing tasks especially at the beginning of the tasks, which might be a sign of differences in task effort. Our results show that NIRS is a sensitive measure to reveal differences in the topographical distribution and time course of the hemodynamic response between distinct swallowing tasks and might be therefore an adequate diagnostic and therapy tool for swallowing difficulties.

Hemodynamic Changes Associated with Interictal Spikes Induced by Acute Models of Focal Epilepsy in Rats: A Simultaneous Electrocorticography and Near-Infrared Spectroscopy Study.

Interictal spikes can be generated by blocking GABAA receptor-mediated inhibition. The nature of the hemodynamic activities associated with interictal spikes in acute models of focal epilepsy based on GABA deactivation has not been determined. We analyzed systemic changes in hemodynamic signals associated with interictal spikes generated by acute models of focal epilepsy. Simultaneous ElectroCorticoGraphy (ECoG) and Near-InfraRed Spectroscopy (NIRS) recordings were obtained in vivo from adult Sprague-Dawley rat brain during semi-periodic focal interictal spikes induced by local cortical application of low doses of Penicillin G (PG) and Bicuculline Methiodide (BM) as GABA deactivation agents. The Finite Impulse Response deconvolution technique was used to estimate the profile of hemodynamic changes in oxyhemoglobin (HbO) and deoxyhemoglobin (HbR) concentrations associated with interictal ECoG spikes in each rat. Our results show that, in both acute models of focal epilepsy, the hemodynamic changes associated with interictal spikes were characterized by pre-spike and post-spike primary NIRS responses, and recovery periods with slight differences in amplitude and latency. The pre-spike period starting at least 2s prior to the onset of ECoG spikes was characterized by a significant decrease in HbO concomitant with an increase in HbR with respect to baseline. The post-spike primary NIRS response exhibited the expected changes described according to the classical view of neurovascular coupling, i.e., a significant increase in HbO and a significant decrease in HbR in response to interictal spikes. The recovery period was characterized by a decreased HbO signal and an increased HbR signal, followed by a return to baseline. Compared to the BM epilepsy model, the PG model was more stable and showed lower variability in the shape, amplitude and latency of the components of spike-related hemodynamic changes. Our findings support a prominent role for pre-spike hemodynamic changes in the initiation of interictal spikes. The mechanism of interactions between neuronal and vascular networks during the pre-spike period constitutes a complex process, resulting in increased sensitivity of the epileptogenic focus to induce neuronal spiking.

A three-dimensional single-scan approach for the measurement of changes in cerebral blood volume, blood flow, and blood oxygenation-weighted signals during functional stimulation

The blood-oxygenation-level-dependent (BOLD) effect reflects ensemble changes in several physiological parameters such as cerebral blood volume (CBV), blood flow (CBF), and cerebral metabolic rate of oxygen (CMRO2). Quantitative BOLD approaches have been developed to estimate CMRO2 dynamics from BOLD, CBF and CBV responses, generally using separate scans. The ability to detect changes in these parameters in a single scan would shorten the total scan time and reduce temporal variations in physiology or neuronal responses. Here, an acquisition strategy, named 3D TRiple-acquisition after Inversion Preparation (3D-TRIP), is demonstrated for 3D acquisition of CBV, CBF, and BOLD signal changes in a single scan by incorporating VASO, FAIR-ASL and T2-prepared BOLD fMRI methods. Using a visual stimulation paradigm, we demonstrate that the activation patterns, relative signal changes, temporal signal-to-noise ratio (tSNR), contrast-to-noise ratio (CNR), and estimated CMRO2 changes during visual stimulation are all comparable between the concurrent imaging proposed here and the separate scans conventionally applied. This approach is expected to provide a useful alternative for quantitative BOLD fMRI studies where information about oxygen metabolism alterations can be extracted from changes in hemodynamic signals associated with CBV, CBF, and blood oxygenation.

Functional brain imaging

Functional magnetic resonance imaging (fMRI) is a non-invasive method that has become one of the major tools for understanding human brain function and in recent years has also been developed for clinical applications. Changes in hemodynamic signals correspond to changes in neuronal activity with good spatial and temporal resolution in fMRI. Using high-field MR systems and increasingly dedicated statistics and postprocessing, activated brain areas can be detected and superimposed on anatomical images. Currently, fMRI data are often combined in multimodal imaging, e. g. with diffusion tensor imaging (DTI) sequences. This method is helping to further understand the physiology of cognitive brain processes and is also being used in a number of clinical applications. In addition to the blood oxygenation level-dependent (BOLD) signals, this article deals with the construction of fMRI investigations, selection of paradigms and evaluation in the clinical routine. Clinically, this method is mainly used in the planning of brain surgery, analyzing the location of brain tumors in relation to eloquent brain areas and the lateralization of language processing. As the BOLD signal is dependent on the strength of the magnetic field as well as other limitations, an overview of recent developments is given. Increases of magnetic field strength (7T), available head coils and advances in MRI analytical methods have led to constant improvement in fMRI signals and experimental design. Especially the depiction of eloquent brain regions can be done easily and quickly and has become an essential part of presurgical planning.

Monitoring Local Regional Hemodynamic Signal Changes during Motor Execution and Motor Imagery Using Near-Infrared Spectroscopy.

The aim of this study was to clarify the topographical localization of motor-related regional hemodynamic signal changes during motor execution (ME) and motor imagery (MI) by using near-infrared spectroscopy (NIRS), as this technique is more clinically expedient than established methods (e.g., fMRI). Twenty right-handed healthy subjects participated in this study. The experimental protocol was a blocked design consisting of 3 cycles of 20 s of task performance and 30 s of rest. The tapping sequence task was performed with their fingers under 4 conditions: ME and MI with the right or left hand. Hemodynamic brain activity was measured with NIRS to monitor changes in oxygenated hemoglobin (oxy-Hb) concentration. Oxy-Hb in the somatosensory motor cortex (SMC) increased significantly only during contralateral ME and showed a significant interaction between task and hand. There was a main effect of hand in the left SMC. Although there were no significant main effects or interactions in the supplemental motor area (SMA) and premotor area (PMA), oxy-Hb increased substantially under all conditions. These results clarified the topographical localization by motor-related regional hemodynamic signal changes during ME and MI by using NIRS.

Hemodynamic Signal Changes Accompanying Execution and Imagery of Swallowing in Patients with Dysphagia: A Multiple Single-Case Near-Infrared Spectroscopy Study.

In the present multiple case study, we examined hemodynamic changes in the brain in response to motor execution (ME) and motor imagery (MI) of swallowing in dysphagia patients compared to healthy matched controls using near-infrared spectroscopy (NIRS). Two stroke patients with cerebral lesions in the right hemisphere, two stroke patients with lesions in the brainstem, and two neurologically healthy control subjects actively swallowed saliva (ME) and mentally imagined to swallow saliva (MI) in a randomized order while changes in concentration of oxygenated hemoglobin (oxy-Hb) and deoxygenated hemoglobin (deoxy-Hb) were assessed. In line with recent findings in healthy young adults, MI and ME of swallowing led to the strongest NIRS signal change in the inferior frontal gyrus in stroke patients as well as in healthy elderly. We found differences in the topographical distribution and time course of the hemodynamic response in dependence on lesion location. Dysphagia patients with lesions in the brainstem showed bilateral hemodynamic signal changes in the inferior frontal gyrus during active swallowing comparable to healthy controls. In contrast, dysphagia patients with cerebral lesions in the right hemisphere showed more unilateral activation patterns during swallowing. Furthermore, patients with cerebral lesions showed a prolonged time course of the hemodynamic response during MI and ME of swallowing compared to healthy controls and patients with brainstem lesions. Brain activation patterns associated with ME and MI of swallowing were largely comparable, especially for changes in deoxy-Hb. Hence, the present results provide new evidence regarding timing and topographical distribution of the hemodynamic response during ME and MI of swallowing in dysphagia patients and may have practical impact on future dysphagia treatment.

Changes in hemodynamic signals accompanying motor imagery and motor execution of swallowing: A near-infrared spectroscopy study

In the present study we investigated hemodynamic changes in the brain in response to motor execution (ME) and motor imagery (MI) of swallowing using near-infrared spectroscopy (NIRS). Previous studies provide evidence that ME and MI of limb movements lead to comparable brain activation patterns indicating the potential value of MI for motor rehabilitation. In this context, identifying brain correlates of MI of swallowing may be potentially useful for the treatment of dysphagia. Fourteen healthy participants actively swallowed water (ME) and mentally imagined to swallow water (MI) in a randomized order while changes in concentration of oxygenated hemoglobin (oxy-Hb) and deoxygenated hemoglobin (deoxy-Hb) were assessed. MI and ME led to the strongest NIRS signal changes in the inferior frontal gyrus. During and after ME, oxy-Hb significantly increased, with a maximum peak around 15s after task onset. In contrast, oxy-Hb decreased during MI compared to a rest period probably because of motor inhibition mechanisms. Changes in deoxy-Hb were largely comparable between MI and ME, especially when participants used a kinesthetic motor imagery strategy during MI compared to no specific strategy. Hence, the present study provides new evidence concerning timing and topographical distribution of the hemodynamic response during ME and MI of swallowing.

A Modified Generalized Series Approach: Application to Sparsely Sampled fMRI

In functional MRI, it is often desirable to reduce the readout duration to make the acquired data less prone to T₂* susceptibility artifacts. In addition, a shorter readout length allows for a shorter minimum TE, which is important for optimizing SNR. This can be achieved by undersampling the k-space. However, the conventional Fourier transform-based reconstruction method suffers from under-sampling artifacts such as high-frequency ringing and loss of resolution. To address this problem, we revisit the constrained-model approach using the generalized-series (GS) which has been proposed to address the undersampling problem for dynamic MRI. We propose a modification to the conventional use of the model in order to reflect small hemodynamic signal changes typical in fMRI. Specifically, while realizing that having high model order is necessary to capture missing information, we found that it is not necessary to span all frequencies of GS basis functions uniformly. Instead, having k -space and GS "sampling" trajectories covering low-frequencies uniformly while spanning high-frequencies sparsely, was observed to be an efficient strategy. The ability of the method over the conventional GS approach in improving resolution of functional images and activation maps while reducing undersampling ringing is demonstrated by simulations and experiments at 3T. Reduction in the readout time allowed an increase of statistical signal power as compared to the fully sampled acquisition. Unlike compressed sensing approaches, the proposed method is linear and hence has lower computational complexity. The method could prove useful for other imaging modalities where the signal change is smaller than the baseline component.

Single-trial coupling of EEG and fMRI during recognition reveals the generators of ERP old/new effects

Event Abstract Back to Event Single-trial coupling of EEG and fMRI during recognition reveals the generators of ERP old/new effects Michael Hoppstädter1, 2*, Christian Bäuchl1, 2, Carsten Diener1, 2, Herta Flor1, 2 and Patric Meyer1, 2 1 Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Department of Cognitive and Clinical Neuroscience, Germany 2 Bernstein Center for Computational Neuroscience Heidelberg/Mannheim, Germany Recognition means the ability to decide if information was encountered previously. This can be featured with additional details from the encoding episode or not. Various behavioural, electrophysiological and imaging studies have pinpointed that two differential processes are involved in recognition memory, namely recollection and familiarity. Recollection describes the conscious retrieval of contextual information about a specific episode, while familiarity means only a feeling of knowing without additional contextual details. These processes may be differentiated electrophysiologically by means of event-related potentials (ERPs). In contrast to correctly rejected new items, items correctly classified as old yield a more positive ERP deflection which is termed old/new effect. One earlier frontally localized old/new effect emerging from about 300 ms after stimulus onset relates to familiarity processing whereas a functionally distinct later parietal effect is associated with recollection. Functional magnetic resonance imaging (fMRI) has revealed that within the medial temporal lobe, extrahippocampal cortical areas and the hippocampus proper support independently recognition based on familiarity or recollection, respectively. In order to examine the relation between hemodynamic changes and the modulation of ERP old/new effects during memory retrieval, we conducted a simultaneous EEG-fMRI study in 16 young healthy volunteers. Standard ERP analyses revealed an early mid-frontal and a later parietal old/new effect, presumably associated to the differential use of familiarity and recollection during recognition. FMRI old/new contrasts showed activity modulation in the hippocampus as well as in the precuneus, the retrosplenial cortex and the medial frontal gyrus. An EEG-informed fMRI analysis was performed to relate single-trial ERP amplitudes to hemodynamic signal changes, thus accounting for trial-to-trial fluctuations. By orthogonalisation to the standard stimulus-coding predictors the variance explained by the trial-to-trial modulation of the old/new effects was isolated. The results complement rare data from intracranial ERP recordings and patient studies. The results from this multimodal fusion analysis will be embedded into biophysically and anatomically detailed models of hippocampal-prefrontal interaction which will in turn generate predictors for the outcome of future imaging studies. Acknowledgements This study was supported by the Bundesministerium für Bildung und Forschung. Keywords: EEG-fMRI, Long-term memory, medial temporal lobe, retrieval Conference: Bernstein Conference 2012, Munich, Germany, 12 Sep - 14 Sep, 2012. Presentation Type: Poster Topic: Learning, plasticity, memory Citation: Hoppstädter M, Bäuchl C, Diener C, Flor H and Meyer P (2012). Single-trial coupling of EEG and fMRI during recognition reveals the generators of ERP old/new effects. Front. Comput. Neurosci. Conference Abstract: Bernstein Conference 2012. doi: 10.3389/conf.fncom.2012.55.00122 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 11 May 2012; Published Online: 12 Sep 2012. * Correspondence: Mr. Michael Hoppstädter, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Department of Cognitive and Clinical Neuroscience, Mannheim, Germany, michael.hoppstaedter@zi-mannheim.de Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Michael Hoppstädter Christian Bäuchl Carsten Diener Herta Flor Patric Meyer Google Michael Hoppstädter Christian Bäuchl Carsten Diener Herta Flor Patric Meyer Google Scholar Michael Hoppstädter Christian Bäuchl Carsten Diener Herta Flor Patric Meyer PubMed Michael Hoppstädter Christian Bäuchl Carsten Diener Herta Flor Patric Meyer Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Mental Hoop Diaries: Emotional Memories of a College Basketball Game in Rival Fans

The rivalry between the men's basketball teams of Duke University and the University of North Carolina-Chapel Hill (UNC) is one of the most storied traditions in college sports. A subculture of students at each university form social bonds with fellow fans, develop expertise in college basketball rules, team statistics, and individual players, and self-identify as a member of a fan group. The present study capitalized on the high personal investment of these fans and the strong affective tenor of a Duke-UNC basketball game to examine the neural correlates of emotional memory retrieval for a complex sporting event. Male fans watched a competitive, archived game in a social setting. During a subsequent functional magnetic resonance imaging session, participants viewed video clips depicting individual plays of the game that ended with the ball being released toward the basket. For each play, participants recalled whether or not the shot went into the basket. Hemodynamic signal changes time locked to correct memory decisions were analyzed as a function of emotional intensity and valence, according to the fan's perspective. Results showed intensity-modulated retrieval activity in midline cortical structures, sensorimotor cortex, the striatum, and the medial temporal lobe, including the amygdala. Positively valent memories specifically recruited processing in dorsal frontoparietal regions, and additional activity in the insula and medial temporal lobe for positively valent shots recalled with high confidence. This novel paradigm reveals how brain regions implicated in emotion, memory retrieval, visuomotor imagery, and social cognition contribute to the recollection of specific plays in the mind of a sports fan.

Predicting the actions of others taps into one's own somatosensory representations—A functional MRI study

Humans have the striking capacity to predict actions performed by their conspecifics. But how exactly do we perform such predictions? Do we use our own action repertoire and our own body to simulate the reaching range of others? In this functional magnetic resonance imaging study static photographs depicting side views of seated human models were presented to participants, who had to predict whether the models could reach a target placed in front of them. The predictions were performed both fast and accurate, but with an overestimation bias as well as higher error rates and slower predictions for targets close to the models’ actual reaching ranges. Specific hemodynamic signal changes were detected in primary and secondary somatosensory cortices, inferior and superior parietal areas, and in right ventral premotor cortex. These findings demonstrate that action prediction in the current context activates a network of areas involved in action recognition, visuo-spatial transformation and somatosensory anticipation. The results are in line with the mirror-neuron system account of action understanding and the notion of the common coding theory that actions are coded in terms of their perceivable effects.

Experimental designs and processing strategies for fMRI studies involving overt verbal responses

Event-related paradigms have been used increasingly in the past few years for the localization of function in tasks involving overt speech. These designs exploit the differences in the temporal characteristics between the rapid motion-induced and the slower hemodynamic signal changes. The optimization of these designs and the best way to analyze the acquired data has not yet been fully explored. The purpose of this study is to investigate various design and analysis strategies for maximizing the detection of function while minimizing task-induced motion artifacts. Both event-related and blocked paradigms can be specifically designed to meet these goals. Various event-related and blocked designs were compared both in simulation and in experiments involving overt word reading in their ability to detect function and to avoid speech-induced motion artifact. A blocked design with task and control durations of 10 s and an event-related design with a minimum stimulus duration (SD) of 5 s and an average interstimulus interval (ISI) of 10 s were found to optimally detect blood oxygenation level-dependent signal changes without significant motion artifact. Ignoring images acquired during the speech can help recover function in areas particularly affected by motion but substantially reduces the detection power in other regions. Using the stimulus timing as an additional regressor to model the motion offers little benefit in practice due to the variability of the motion-induced signal change.