Neurobiological Causal Models of Language Processing.

The language faculty is physically realized in the neurobiological infrastructure of the human brain. Despite significant efforts, an integrated understanding of this system remains a formidable challenge. What is missing from most theoretical accounts is a specification of the neural mechanisms that implement language function.

The Tripod neuron: a minimal structural reduction of the dendritic tree.

Neuron models with explicit dendritic dynamics have shed light on mechanisms for coincidence detection, pathway selection and temporal filtering. However, it is still unclear which morphological and physiological features are required to capture these phenomena. In this work, we introduce the Tripod neuron model and propose a minimal structural reduction of the dendritic tree that is able to reproduce these computations.

Neuronal spike-rate adaptation supports working memory in language processing.

Language processing involves the ability to store and integrate pieces of information in working memory over short periods of time. According to the dominant view, information is maintained through sustained, elevated neural activity. Other work has argued that short-term synaptic facilitation can serve as a substrate of memory.

Language ERPs reflect learning through prediction error propagation.

Event-related potentials (ERPs) provide a window into how the brain is processing language. Here, we propose a theory that argues that ERPs such as the N400 and P600 arise as side effects of an error-based learning mechanism that explains linguistic adaptation and language learning. We instantiated this theory in a connectionist model that can simulate data from three studies on the N400 (amplitude modulation by expectancy, contextual constraint, and sentence position), five studies on the P600 (agreement, tense, word category, subcategorization and garden-path sentences), and a study on the semantic P600 in role reversal anomalies.

Evaluation of sentinel lymph node biopsy prior to axillary lymph node dissection: the role of isolated tumor cells/micrometastases and multifocality/multicentricity-a retrospective study of 1214 breast cancer patients.

Purpose: Sentinel lymph node biopsy (SLNB) alone has thus become an accepted surgical approach for patients with limited axillary metastatic disease. We investigated to what extent isolated tumor cells (ITC) or micrometastasis in SLNBs is associated with proven tumor cells or metastasis in non-sentinel lymph nodes. Furthermore, we investigated the feasibility of SLNB in multifocal and multicentric tumors as both entities have been considered a contraindication for this technique.