ABSTRACT
Simple multisensory manipulations can induce the illusory misattribution of external objects to one's own body, allowing to experimentally investigate body ownership. In this context, body ownership has been conceptualized as the result of the online Bayesian optimal estimation of the probability that one object belongs to the body from the congruence of multisensory inputs. This idea has been highly influential, as it provided a quantitative basis to bottom-up accounts of self-consciousness. However, empirical evidence fully supporting this view is scarce, as the optimality of the putative inference process has not been assessed rigorously. This pre-registered study aimed at filling this gap by testing a Bayesian model of hand ownership based on spatial and temporal visuo-proprioceptive congruences. Model predictions were compared to data from a virtual-reality reaching task, whereby reaching errors induced by a spatio-temporally mismatching virtual hand have been used as an implicit proxy of hand ownership. To rigorously test optimality, we compared the Bayesian model versus alternative non-Bayesian models of multisensory integration, and independently assess unisensory components and compare them to model estimates. We found that individually measured values of proprioceptive precision correlated with those fitted from our reaching task, providing compelling evidence that the underlying visuo-proprioceptive integration process approximates Bayesian optimality. Furthermore, reaching errors correlated with explicit ownership ratings at the single individual and trial level. Taken together, these results provide novel evidence that body ownership, a key component of self-consciousness, can be truly described as the bottom-up, behaviourally optimal processing of multisensory inputs.
Subject(s)
Illusions , Touch Perception , Humans , Visual Perception , Body Image , Ownership , Bayes Theorem , Brain , Proprioception , Hand , Models, StatisticalABSTRACT
Revisión de 100 casos operados de HED. 76 casos fueron varones. El mecanismo fue el accidente de tránsito o la caída en 81 casos. La historia de alteración de conciencia se registró en 82 pacientes. Se encontraron sin focalidad al ingreso 31 casos. El HED se presentó supratentorial en 87. El tiempo promedio entre el traumatismo encéfalo craneano (TEC) y la cirugía fue de 33 horas. No hubo recidivas post cirugía. La mortalidad alcanzó a 5 casos. Cerca de un 25 porciento de los pacientes se presentan concientes pero con focalidad o signos de hipertensión intracraneal. Se observa relación directa entre estado neurológico de ingreso y al alta
Subject(s)
Humans , Male , Female , Infant, Newborn , Infant , Child, Preschool , Adolescent , Adult , Middle Aged , Brain Injuries/surgery , Hematoma, Epidural, Cranial/surgery , Accidents, Traffic , Glasgow Coma Scale , Retrospective StudiesABSTRACT
En el manejo precoz de los T.R.M. conviene procurar o considerar lo siguiente: 1. No agregar daño. 2. Examen neurológico y radiografía en sala de urgencias. 3. Si la lesión es estable poner collar en cama plana. 4. Si la lesión es inestable o con déficit neurológico, poner tracción con estribo de Crutzfield. 5. Si hay dudas de diagnóstico poner tracción. 6. Corticoides. 7. Cuidar al máximo los enfermos con lesión neurológica parcial. 8. La cirugía precoz no tiene lugar en la terapia, salvo excepciones