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Ambulatory diffuse optical tomography (aDOT) is based on near-infrared spectroscopy (NIRS) and enables three-dimensional imaging of regional hemodynamics and oxygen consumption during a person’s normal activities. Although NIRS has been previously used for muscle assessment, it has been notably limited in terms of the number of channels measured, the extent to which subjects can be ambulatory, and/or the ability to simultaneously acquire synchronized auxiliary data such as electromyography (EMG) or electrocardiography (ECG). We describe the development of a prototype aDOT system, called NINscan-M, capable of ambulatory tomographic imaging as well as simultaneous auxiliary multimodal physiological monitoring. Powered by four AA size batteries and weighing 577 g, the NINscan-M prototype can synchronously record 64-channel NIRS imaging data, eight channels of EMG, ECG, or other analog signals, plus force, acceleration, rotation, and temperature for 24+ h at up to 250 Hz. We describe the system’s design, characterization, and performance characteristics. We also describe examples of isometric, cycle ergometer, and free-running ambulatory exercise to demonstrate tomographic imaging at 25 Hz. NINscan-M represents a multiuse tool for muscle physiology studies as well as clinical muscle assessment. [ABSTRACT FROM AUTHOR]

The feasibility and utility of wearable 24-h multimodality neuromonitoring during daily activities are demonstrated. We have developed a fourth-generation ambulatory near infrared spectroscopy device, namely NINscan 4. NINscan 4 enables recording of brain function (via cerebral hemodynamics), systemic hemodynamics, electrocardiography, and actigraphy simultaneously and continuously for up to 24 h at 250-Hz sampling rate, during (and with minor restriction to) daily activities. We present initial 24-h human subject test results, with example analysis including (1) comparison of cerebral perfusion and oxygenation changes during wakefulness and sleep over a 24-h period and (2) capturing of hemodynamic changes prior, during and after sudden waken up in the night during sleep. These results demonstrate the first ambulatory 24-h cerebral and systemic hemodynamics monitoring, and its unique advantages including long-term data collection and analysis capability, ability to catch unpredictable transient events during activities of daily living, as well as coregistered multimodality analysis capabilities. These results also demonstrate that NINscan 4's motion artifact at 1- head move- g ment is smaller than physiological hemodynamic fluctuations during motionless sleep. The broader potential of this technology is also discussed. [ABSTRACT FROM AUTHOR]

Primary objective: To determine test-re-test reliability of the Hopkins Verbal Learning Test-Revised (HVLT-R) in a group of individuals with traumatic brain injury (TBI). Research design: Single-group repeated measures design. Methods and procedures: Seventy-five individuals with TBI were administered the HVLT-R twice, with 6-8 weeks between the two test sessions. Main outcomes and results: Test-re-test reliability on HVLT-R scoring parameters ranged from 0.537-0.818, with seven of the eight scoring parameters exhibiting r > 0.6. At re-test, scores did not significantly change on any of the eight HVLT-R scoring parameters. Conclusions: HVLT-R use with individuals with TBI is supported. Test-re-test reliability of total recall and delayed recall sub-scores was particularly high. [ABSTRACT FROM AUTHOR]

Primary objective: To determine test–re-test reliability of the VIrtual Planning Test (VIP) in a group of individuals with traumatic brain injury (TBI). Research design: Single-group repeated measures design. Methods and procedures: Seventy-five individuals with TBI were administered the VIP, with 6–8 weeks between the two test sessions. Main outcomes and results: Test–re-test reliability on VIP scoring parameters—as measured by Pearson correlation coefficients—ranged from 0.341–0.855, with five of the seven scoring parameters exhibiting r > 0.6. Conclusions: Based on the findings of the current study, the VIP has overall moderate test–re-test reliability when administered to individuals with TBI. Some VIP scoring parameters, i.e. Total correct/accuracy and Total absence, demonstrated high test–re-test reliability. Others, i.e. Planning time and Total wrong order, demonstrated low test–re-test reliability. [ABSTRACT FROM AUTHOR]

There has been substantial recent growth in the use of non-invasive optical brain imaging in studies of human brain function in health and disease. Near-infrared neuroimaging (NIN) is one of the most promising of these techniques and, although NIN hardware continues to evolve at a rapid pace, software tools supporting optical data acquisition, image processing, statistical modeling, and visualization remain less refined. Python, a modular and computationally efficient development language, can support functional neuroimaging studies of diverse design and implementation. In particular, Python's easily readable syntax and modular architecture allow swift prototyping followed by efficient transition to stable production systems. As an introduction to our ongoing efforts to develop Python software tools for structural and functional neuroimaging, we discuss: (i) the role of non-invasive diffuse optical imaging in measuring brain function, (ii) the key computational requirements to support NIN experiments, (iii) our collection of software tools to support NIN, called NinPy, and (iv) future extensions of these tools that will allow integration of optical with other structural and functional neuroimaging data sources. Source code for the software discussed here will be made available at www.nmr.mgh.harvard.edu/Neural_SystemsGroup/software.html.