19 research outputs found
Neural and behavioral traces of error awareness
Monitoring for errors and behavioral adjustments after errors are essential for daily life. A question that has not been addressed systematically yet, is whether consciously perceived errors lead to different behavioral adjustments compared to unperceived errors. Our goal was to develop a task that would enable us to study different commonly observed neural correlates of error processing and post-error adjustments in their relation to error awareness and accuracy confidence in a single experiment. We assessed performance in a new number judgement error awareness task in 70 participants. We used multiple, robust, single-trial EEG regressions to investigate the link between neural correlates of error processing (e.g., error-related negativity (ERN) and error positivity (Pe)) and error awareness. We found that only aware errors had a slowing effect on reaction times in consecutive trials, but this slowing was not accompanied by post-error increases in accuracy. On a neural level, error awareness and confidence had a modulating effect on both the ERN and Pe, whereby the Pe was most predictive of participants’ error awareness. Additionally, we found partial support for a mediating role of error awareness on the coupling between the ERN and behavioral adjustments in the following trial. Our results corroborate previous findings that show both an ERN/Pe and a post-error behavioral adaptation modulation by error awareness. This suggests that conscious error perception can support meta-control processes balancing the recruitment of proactive and reactive control. Furthermore, this study strengthens the role of the Pe as a robust neural index of error awareness
Orbital Infantile Myofibroma: a Case Report and Clinicopathologic Review of 24 Cases from the Literature
Isolated orbital infantile myofibroma are rare tumors in the head and neck. The mass-like clinical presentation and variable histologic features result in frequent misdiagnosis and potentially inappropriate clinical management. There are only a few reported cases in the English literature. Twenty-four patients with orbital infantile myofibroma or myofibromatosis were compiled from the English literature (Medline 1960–2011) and integrated with this case report. The patients included 14 males and 10 females, aged newborn to 10 years (mean, 34.8 months), who presented with a painless mass in the infra- or supraorbital regions, usually increasing in size andassociated with exophthalmos (n = 5). Females were on average older than their male counterparts (38.9 vs. 31.9 months, respectively; P = 0.71). The tumors were twice as frequent on the left (n = 16) than right (n = 8). Patients experienced symptoms for an average of 2.7 months before clinical presentation. The tumors involved the bone (n = 17) or the soft tissues (n = 7) of the orbit, with extension into the nasal or oral cavity (n = 3). The mean size was 3.0 cm, with a statistically significant difference between males and females (mean: 3.9 vs. 1.82; P = 0.0047), but without any differences based on age at presentation (P = 0.25), duration of symptoms (P = 0.66), or bone or soft tissue involvement (P = 0.51). Grossly, all tumors were well-circumscribed, firm to rubbery, homogenous, and white–grey. Histologically, the tumors were biphasic, showing whorled and nodular areas of fusiform cells with extracellular collagen, mixed with a population of small, primitive-appearing, darkly staining cells. Necrosis was not present, but mitoses could be seen. Tumors with immunohistochemistry performed showed strong and diffuse smooth muscle actin and vimentin immunoreactivity, but were negative with muscle specific actin, desmin, MYOD1, myogenin, S100 protein, GFAP, keratin, CD31, 34, Factor VIIIR-Ag, and CD45RB. The principle histologic differential diagnosis includes juvenile hyaline fibromatosis, fibrous hamartoma of infancy, fibromatosis coli, leiomyoma, infantile hemangiopericytoma, infantile fibrosarcoma, Ewing sarcoma/primitive neuroectodermal tumor, and lymphoma. All patients were managed with surgery. Recurrences developed in two patients at 4 and 6 months, respectively. Follow-up data was available on all but two patients (n = 22). These patients were either alive without evidence of disease (n = 18), alive but with disease (n = 3), or had died unrelated to this disease (i.e., neuroblastoma, n = 1). Orbital infantile myofibroma is a rare tumor, presenting in infancy as an enlarging mass of the orbit, with characteristic histomorphologic and immunophenotypic features. Orbital disease is usually isolated rather than part of systemic disease, and shows an excellent long-term prognosis, making appropriate separation from other conditions important