Phenomenological modelling of non-volatile memory threshold voltage shift induced by nonlinear ionization with a femtosecond laser.

The behaviour of semiconductor materials and devices subjected to femtosecond laser irradiation has been under scrutiny, for many reasons, during the last decade. In particular, recent works have shown that the specific functionality and/or geometry of semiconductor devices, among which non-volatile memory (NVM) devices hold a special place, could be used to improve the knowledge about ultrafast laser-semiconductor interactions. So far, such an approach has been applied to draw conclusions about the spatio-temporal properties of laser propagation in bulk materials. Here, by comparing the evolution of the electrical characteristics of Flash cells under the cumulative effect of repeated femtosecond laser pulses with first-order physical considerations and TCAD (Technology Computer Aided Design) simulations, we clearly establish the role of the carriers created by nonlinear ionization on the functionality of the structures. The complete electrical analysis informs indirectly on the energy of the laser-produced free-carriers which, to date, was almost inaccessible by an experimental method applicable to the bulk of a material. Establishing the link between the carrier energy and laser parameters is of major importance to improve the comprehension of the nonlinear ionization mechanisms associated to intense laser-semiconductor interactions and applied in various fields from microelectronics to laser micromachining.

Yes they can! An approach to observational learning in low-functioning children with autism.

Learning by doing and learning by observing are two facets of the tight coupling between perception and action discovered at the brain level. Developmental studies of observational learning still remain rare and even more rare are studies documenting the capacities of low-functioning children with autism to learn by observation. In the first investigation of this question, twenty nonverbal children with autism with a developmental age of 24 and 36 months, and twenty matched typical children, were presented with an experimental box requiring that a hierarchical sequence of subgoals be performed before it could be opened. A 9-day testing procedure included four presentations of the red box and two video demonstrations of how to open it. Two scores were computed, one concerning the number of sub-goals fulfilled and the other the relevant manipulations of the material. Within-group analyses revealed that only the typical children learned partly or fully the sequence of subgoals after the first video-demonstration. The addition of a second demonstration allowed the two subgroups with autism to learn partly or fully the sequence of subgoals. The differences between learning to manipulate and learning to produce a goal are discussed in terms of relationships between understanding actions and understanding action-effect relations.

Human newborns match tongue protrusion of disembodied human and robotic mouths.

No evidence had been provided so far of newborns' capacity to give a matching response to 2D stimuli. We report evidence from 18 newborns who were presented with three types of stimuli on a 2D screen. The stimuli were video-recorded displays of tongue protrusion shown by: (a) a human face, (b) a human tongue from a disembodied mouth, and (c) an artificial tongue from a robotic mouth. Compared to a baseline condition, neonates increased significantly their tongue protrusion when seeing disembodied human and artificial tongue movements, but not when seeing a 2D full-face protruding tongue. This result was interpreted as revealing the exploration of top-heavy patterns of the 2D face that distracted infants' attention from the tongue. Results also showed progressively more accurate matching (full tongue protrusion) throughout repeated exposure to each kind of stimulus. Such findings are not in line with the predictions of the innate releasing mechanism (IRM) model or of the oral exploration hypothesis. They support the active intermodal mapping (AIM) hypothesis that emphasizes not only the importance of repeated experience, as would the associative sequence learning (ASL) hypothesis, but also predicts a differential learning and progressive correction of the response adapted to each stimulus.