La dépendance à l'égard de l'environnement lors de lésions cérébrales: conduites d'imitation, de préhension et d'utilisation [Environmental dependence in brain lesions: imitative behavior, prehension and utilization].

This paper reviews the literature on clinical signs such as imitation behavior, grasp reaction, manipulation of tools, utilization behavior, environmental dependency, hyperlexia, hypergraphia and echolalia. Some aspects of this semiology are of special interest because they refer to essential notions such as free-will and autonomy.

Major depressive disorders in the general hospital: how to implement guidelines.

OBJECTIVE: An implementation study that evaluated the impact of previously adopted guidelines on the clinical practice of medical residents was conducted to improve the recognition and treatment of major depressive disorders (MDDs) in hospitalized patients with somatic diseases. METHODS: Guidelines were implemented in two wards (ENT and oncology) using intranet diffusion, interactive sessions with medical residents, and support material. Discharge letters of 337 and 325 patients, before and after the intervention, respectively, were checked for statement of diagnosis or treatment of MDDs and, in a post hoc analysis, for any mention about psychiatric management. RESULTS: No difference was found in the number of diagnosed or treated MDDs before and after the intervention. However, significantly more statements about psychological status (29/309 vs. 13/327) and its management (36/309 vs. 19/327) were observed after the intervention (P<.01). CONCLUSION: The intervention was not successful in improving the management of MDDs. However, a possible effect on general psychological aspects of medical diseases was observed.

Maturation and Functional Integration of New Granule Cells into the Adult Hippocampus.

The adult hippocampus generates functional dentate granule cells (GCs) that release glutamate onto target cells in the hilus and cornus ammonis (CA)3 region, and receive glutamatergic and γ-aminobutyric acid (GABA)ergic inputs that tightly control their spiking activity. The slow and sequential development of their excitatory and inhibitory inputs makes them particularly relevant for information processing. Although they are still immature, new neurons are recruited by afferent activity and display increased excitability, enhanced activity-dependent plasticity of their input and output connections, and a high rate of synaptogenesis. Once fully mature, new GCs show all the hallmarks of neurons generated during development. In this review, we focus on how developing neurons remodel the adult dentate gyrus and discuss key aspects that illustrate the potential of neurogenesis as a mechanism for circuit plasticity and function.