Merve Kaptan

All Publications

• Exploring Neuronal Underpinnings of Emotional Regulation of Pain in Fibromyalgia Patients Kaptan, M., Pfyffer, D., Law, C. W., Oliva, V., Weber, K., Glover, G., Mackey, S. CHURCHILL LIVINGSTONE. 2024: 47

  View details for Web of Science ID 001282167300210

• Which Types of Ruminative Thinking Style Predict Worse Depression, Anxiety, and Anger Symptoms in Chronic Pain Patients? Konstantopoulos, C. G., Kaptan, M., Mackey, S. C., You, D. S. CHURCHILL LIVINGSTONE. 2024: 65-66

  View details for Web of Science ID 001282167300293

• Which Types of Rumination Will Predict Longitudinal Physical and Psychological Status in Patients with Chronic Pain? Kaptan, M., Konstantopoulos, C. G., Mackey, S. C., You, D. S. CHURCHILL LIVINGSTONE. 2024: 65

  View details for Web of Science ID 001282167300292

• Imaging Corticospinal Correlates of Aberrant Pain Processing and Modulation in Fibromyalgia Using Combined Brain-Spinal Cord Functional Magnetic Resonance Imaging Pfyffer, D., Kaptan, M., Law, C. W., Weber, K. A., Oliva, V., Bedard, S., Maronesy, T., Glover, G. H., Mackey, S. CHURCHILL LIVINGSTONE. 2024: 47-48

  View details for Web of Science ID 001282167300214

• Recent developments and future avenues for human corticospinal neuroimaging. Frontiers in human neuroscience Kaptan, M., Pfyffer, D., Konstantopoulos, C. G., Law, C. S., Weber Ii, K. A., Glover, G. H., Mackey, S. 2024; 18: 1339881

  Abstract

  Non-invasive neuroimaging serves as a valuable tool for investigating the mechanisms within the central nervous system (CNS) related to somatosensory and motor processing, emotions, memory, cognition, and other functions. Despite the extensive use of brain imaging, spinal cord imaging has received relatively less attention, regardless of its potential to study peripheral communications with the brain and the descending corticospinal systems. To comprehensively understand the neural mechanisms underlying human sensory and motor functions, particularly in pathological conditions, simultaneous examination of neuronal activity in both the brain and spinal cord becomes imperative. Although technically demanding in terms of data acquisition and analysis, a growing but limited number of studies have successfully utilized specialized acquisition protocols for corticospinal imaging. These studies have effectively assessed sensorimotor, autonomic, and interneuronal signaling within the spinal cord, revealing interactions with cortical processes in the brain. In this mini-review, we aim to examine the expanding body of literature that employs cutting-edge corticospinal imaging to investigate the flow of sensorimotor information between the brain and spinal cord. Additionally, we will provide a concise overview of recent advancements in functional magnetic resonance imaging (fMRI) techniques. Furthermore, we will discuss potential future perspectives aimed at enhancing our comprehension of large-scale neuronal networks in the CNS and their disruptions in clinical disorders. This collective knowledge will aid in refining combined corticospinal fMRI methodologies, leading to the development of clinically relevant biomarkers for conditions affecting sensorimotor processing in the CNS.

  View details for DOI 10.3389/fnhum.2024.1339881

  View details for PubMedID 38332933

  View details for PubMedCentralID PMC10850311

• Reliability of task-based fMRI in the dorsal horn of the human spinal cord. bioRxiv : the preprint server for biology Dabbagh, A., Horn, U., Kaptan, M., Mildner, T., Müller, R., Lepsien, J., Weiskopf, N., Brooks, J. C., Finsterbusch, J., Eippert, F. 2023

  Abstract

  The application of functional magnetic resonance imaging (fMRI) to the human spinal cord is still a relatively small field of research and faces many challenges. Here we aimed to probe the limitations of task-based spinal fMRI at 3T by investigating the reliability of spinal cord blood oxygen level dependent (BOLD) responses to repeated nociceptive stimulation across two consecutive days in 40 healthy volunteers. We assessed the test-retest reliability of subjective ratings, autonomic responses, and spinal cord BOLD responses to short heat pain stimuli (1s duration) using the intraclass correlation coefficient (ICC). At the group level, we observed robust autonomic responses as well as spatially specific spinal cord BOLD responses at the expected location, but no spatial overlap in BOLD response patterns across days. While autonomic indicators of pain processing showed good-to-excellent reliability, both β-estimates and z-scores of task-related BOLD responses showed poor reliability across days in the target region (gray matter of the ipsilateral dorsal horn). When taking into account the sensitivity of gradient-echo echo planar imaging (GE-EPI) to draining vein signals by including the venous plexus in the analysis, we observed BOLD responses with good reliability across days. Taken together, these results demonstrate that heat pain stimuli as short as one second are able to evoke a robust and spatially specific BOLD response, which is however strongly variable within participants across time, resulting in low reliability in the dorsal horn gray matter. Further improvements in data acquisition and analysis techniques are thus necessary before event-related spinal cord fMRI as used here can be reliably employed in longitudinal designs or clinical settings.

  View details for DOI 10.1101/2023.12.22.572825

  View details for PubMedID 38187724

  View details for PubMedCentralID PMC10769329

• Reliability of resting-state functional connectivity in the human spinal cord: assessing the impact of distinct noise sources. NeuroImage Kaptan, M., Horn, U., Vannesjo, S. J., Mildner, T., Weiskopf, N., Finsterbusch, J., Brooks, J. C., Eippert, F. 2023: 120152

  Abstract

  The investigation of spontaneous fluctuations of the blood-oxygen-level-dependent (BOLD) signal has recently been extended from the brain to the spinal cord, where it has stimulated interest from a clinical perspective. A number of resting-state functional magnetic resonance imaging (fMRI) studies have demonstrated robust functional connectivity between the time series of BOLD fluctuations in bilateral dorsal horns and between those in bilateral ventral horns, in line with the functional neuroanatomy of the spinal cord. A necessary step prior to extension to clinical studies is assessing the reliability of such resting-state signals, which we aimed to do here in a group of 45 healthy young adults at the clinically prevalent field strength of 3T. When investigating connectivity in the entire cervical spinal cord, we observed fair to good reliability for dorsal-dorsal and ventral-ventral connectivity, whereas reliability was poor for within- and between-hemicord dorsal-ventral connectivity. Considering how prone spinal cord fMRI is to noise, we extensively investigated the impact of distinct noise sources and made two crucial observations: removal of physiological noise led to a reduction in functional connectivity strength and reliability - due to the removal of stable and participant-specific noise patterns - whereas removal of thermal noise considerably increased the detectability of functional connectivity without a clear influence on reliability. Finally, we also assessed connectivity within spinal cord segments and observed that while the pattern of connectivity was similar to that of whole cervical cord, reliability at the level of single segments was consistently poor. Taken together, our results demonstrate the presence of reliable resting-state functional connectivity in the human spinal cord even after thoroughly accounting for physiological and thermal noise, but at the same time urge caution if focal changes in connectivity (e.g. due to segmental lesions) are to be studied, especially in a longitudinal manner.

  View details for DOI 10.1016/j.neuroimage.2023.120152

  View details for PubMedID 37142169

• Exploring Corticospinal Functional Connectome Using Resting-State Functional Magnetic Resonance Imaging Kaptan, M., Law, C. W., Weber, K., Pfyffer, D., Zhang, X., Maronesy, T., Glover, G., Mackey, S. CHURCHILL LIVINGSTONE. 2023: 17-18

  View details for Web of Science ID 000995432100047

• Imaging Noxious Thermal Intensity Encoding Along The Neuraxis Using Simultaneous Spinal Cord-Brain Functional Magnetic Resonance Imaging Pfyffer, D., Law, C. W., Weber, K. A., Kaptan, M., Maronesy, T., Glover, G. H., Mackey, S. CHURCHILL LIVINGSTONE. 2023: 76

  View details for Web of Science ID 000995432100203