Objectives:We aim to better understand the silent period (SP), an inhibitory counterpart to the well-known motor evoked potential (MEP) elicited by transcranial magnetic stimulation (TMS), in individuals with spinal cord injury (SCI).Setting: Veterans Affairs Hospital in New York.Methods: Electromyographic responses were measured in the target abductor pollicis brevis at rest (TMS at 120% of resting motor threshold (RMT)) and during maximal effort (TMS at 110% of RMT). Participants with chronic cervical SCI (n=9) and able-bodied volunteers (n=12) underwent between 3-7 sessions of stimulation on separate days. The primary outcomes were the magnitude and reliability of SP duration, resting and active MEP amplitudes, and RMT.Results: SCI participants showed significantly lower MEP amplitudes compared to AB participants. SCI SP duration was not significantly different from AB SP duration. SP duration demonstrated reduced intra-participant variability within and across sessions compared with MEP amplitudes. SCI participants also demonstrated a higher prevalence of SP 'interruptions' compared to AB participants. Conclusions: SP reflects a balance between corticospinal excitatory and inhibitory processes.SP duration is more reliable within and across multiple sessions than MEP amplitude.

Objective: We aim to better understand the silent period (SP), an inhibitory counterpart to the well-known motor evoked potential (MEP) elicited by transcranial magnetic stimulation (TMS), in individuals with spinal cord injury (SCI). Methods: Electromyographic responses were measured in the target abductor pollicis brevis at rest (TMS at 120% of resting motor threshold (RMT)) and during maximal effort (TMS at 110% of RMT). Participants with chronic cervical SCI (n=9) and able-bodied volunteers (n=12) underwent between 3-7 sessions of stimulation on separate days. The primary outcomes were the magnitude and reliability of SP duration, resting and active MEP amplitudes, and RMT. Results: SCI participants showed significantly increased RMT, decreased MEP amplitudes, and non-significantly longer SP duration compared to AB participants. In contrast to high inter-participant variability, SP duration demonstrated reduced intra-participant variability within and across sessions compared with resting and active MEP amplitudes. SCI participants also demonstrated a higher prevalence of SP "interruptions" compared to AB participants. Conclusions: SP reflects a balance between corticospinal excitatory and inhibitory processes. SP duration is more reliable within and across multiple sessions than MEP amplitude. Significance: The higher reliability of SP duration may make it a useful outcome measure for future trials of SCI interventions.

Factitious disorder, a disorder characterized by the falsification of symptoms to obtain primary gain, continues to be one of the more challenging cases that psychiatrists encounter. We describe a case of a woman we treated on the medical unit who falsified several of her symptoms but also was diagnosed with Yao syndrome, a disease that can also cause unexplained symptoms such as abdominal pain and fever. We navigate the difficulties in managing this type of patient and comanaging her with medicine and rheumatology. Although the prevalence of factitious disorder is anywhere from 1% to 2% of patients on the medical floor, they typically utilize a disproportionate number of resources. Despite this, the literature is still inconclusive when it comes to the management and treatment approaches. More study is warranted on this complex and burdensome illness.

ObjectiveTo increase our knowledge of corticospinal excitability changes in persons with spinal cord injury (SCI) by comparing the cortical silent periods (CSPs) of persons with chronic, incomplete cervical SCI to the CSPs of able‐bodied (AB) volunteers.MethodsThe CSP is a corticospinal inhibitory response (1). It appears as gap in electromyographic (EMG) activity of a voluntarily contracting muscle due to transcranial magnetic stimulation (TMS) delivered to the motor cortex (see Figure A). We measured TMS‐induced CSPs in 5 participants with chronic, incomplete cervical SCI and 5 AB volunteers as an exploratory outcome of a larger study assessing the effects of non‐invasive stimulation in persons with and without SCI. EMG data was collected from the abductor pollicis brevis muscle of the dominant hand in each subject. We recorded a total of 139 CSPs in the SCI participants and 176 in the AB participants. Further analysis of 4 more SCI subjects and 10 more AB subjects is ongoing.ResultsThe preliminary results suggest that the average CSP duration of the SCI group (89 ± 34 ms) was less than that of the AB group (116 ± 30 ms). While statistically insignificant, (p = 0.230; Figure B), our results corroborate previous findings of shortened CSPs in persons with SCI (2). Moreover, the proportion of CSPs with at least one “interruption,” visualized as a momentary spike in EMG activity lasting 5–10 ms (see Figure C), was higher in the SCI group (14.48% of CSPs) than in the AB group (2.56% of CSPs; ns; Figure D).ConclusionsOur preliminary findings, of shorter CSP duration and higher frequency of CSP interruptions in subjects with SCI, may imply that cortical inhibitory pathways are damaged or less excitable in persons with SCI. CSP parameters may be valuable outcome measures in the study of SCI.Support or Funding InformationNew York Spinal Cord Injury Research Board (DOH01‐CARTID‐2015‐00037)This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.