Practice of a novel task leads to improved performance. The brain mechanisms associated with prac... more Practice of a novel task leads to improved performance. The brain mechanisms associated with practice-induced improvement in performance are largely unknown. To address this question we have examined the functional anatomy of the human brain with positron emission tomography (PET) during the naive and practiced performance of a simple verbal response selection task (saying an appropriate verb for a visually presented noun). As a control state, subjects were asked to repeat the visually presented nouns. Areas of the brain most active during naive performance (anterior cingulate, left prefrontal and left posterior temporal cortices, and the right cerebellar hemisphere), compared to repeating the visually presented nouns, were all significantly less active during practiced performance. These changes were accompanied by changes in the opposite direction in sylvian-insular cortex bilaterally and left medial extrastriate cortex. In effect, brief practice made the cortical circuitry used for verbal response selection indistinguishable from simple word repetition. Introduction of a novel list of words reversed the learning-related effects. These results indicate that two distinct circuits can be used for verbal response selection and normal subjects can change the brain circuits used during task performance following less than 15 min of practice. One critical factor in determining the circuitry used appears to be the degree to which a task is learned or automatic.
Proceedings of The National Academy of Sciences, 2002
The Arabidopsis thaliana SOS1 protein is a putative Na ؉ ͞H ؉ antiporter that functions in Na ؉ e... more The Arabidopsis thaliana SOS1 protein is a putative Na ؉ ͞H ؉ antiporter that functions in Na ؉ extrusion and is essential for the NaCl tolerance of plants. sos1 mutant plants share phenotypic similarities with mutants lacking the protein kinase SOS2 and the Ca 2؉ sensor SOS3. To investigate whether the three SOS proteins function in the same response pathway, we have reconstituted the SOS system in yeast cells. Expression of SOS1 improved the Na ؉ tolerance of yeast mutants lacking endogenous Na ؉ transporters. Coexpression of SOS2 and SOS3 dramatically increased SOS1dependent Na ؉ tolerance, whereas SOS2 or SOS3 individually had no effect. The SOS2͞SOS3 kinase complex promoted the phosphorylation of SOS1. A constitutively active form of SOS2 phosphorylated SOS1 in vitro independently of SOS3, but could not fully substitute for the SOS2͞SOS3 kinase complex for activation of SOS1 in vivo. Further, we show that SOS3 recruits SOS2 to the plasma membrane. Although sos1 mutant plants display defective K ؉ uptake at low external concentrations, neither the unmodified nor the SOS2͞SOS3-activated SOS1 protein showed K ؉ transport capacity in vivo, suggesting that the role of SOS1 on K ؉ uptake is indirect. Our results provide an example of functional reconstitution of a plant response pathway in a heterologous system and demonstrate that the SOS1 ion transporter, the SOS2 protein kinase, and its associated Ca 2؉ sensor SOS3 constitute a functional module. We propose a model in which SOS3 activates and directs SOS2 to the plasma membrane for the stimulatory phosphorylation of the Na ؉ transporter SOS1.
El presente trabajo pretende ofrecer una experiencia de Musicoterapia realizada en el marco de un... more El presente trabajo pretende ofrecer una experiencia de Musicoterapia realizada en el marco de un Centro de Salud Mental. La Musicoterapia está incluída dentro de las actividades que realizan los pacientes del Hospital de día.
Practice of a novel task leads to improved performance. The brain mechanisms associated with prac... more Practice of a novel task leads to improved performance. The brain mechanisms associated with practice-induced improvement in performance are largely unknown. To address this question we have examined the functional anatomy of the human brain with positron emission tomography (PET) during the naive and practiced performance of a simple verbal response selection task (saying an appropriate verb for a visually presented noun). As a control state, subjects were asked to repeat the visually presented nouns. Areas of the brain most active during naive performance (anterior cingulate, left prefrontal and left posterior temporal cortices, and the right cerebellar hemisphere), compared to repeating the visually presented nouns, were all significantly less active during practiced performance. These changes were accompanied by changes in the opposite direction in sylvian-insular cortex bilaterally and left medial extrastriate cortex. In effect, brief practice made the cortical circuitry used for verbal response selection indistinguishable from simple word repetition. Introduction of a novel list of words reversed the learning-related effects. These results indicate that two distinct circuits can be used for verbal response selection and normal subjects can change the brain circuits used during task performance following less than 15 min of practice. One critical factor in determining the circuitry used appears to be the degree to which a task is learned or automatic.
Proceedings of The National Academy of Sciences, 2002
The Arabidopsis thaliana SOS1 protein is a putative Na ؉ ͞H ؉ antiporter that functions in Na ؉ e... more The Arabidopsis thaliana SOS1 protein is a putative Na ؉ ͞H ؉ antiporter that functions in Na ؉ extrusion and is essential for the NaCl tolerance of plants. sos1 mutant plants share phenotypic similarities with mutants lacking the protein kinase SOS2 and the Ca 2؉ sensor SOS3. To investigate whether the three SOS proteins function in the same response pathway, we have reconstituted the SOS system in yeast cells. Expression of SOS1 improved the Na ؉ tolerance of yeast mutants lacking endogenous Na ؉ transporters. Coexpression of SOS2 and SOS3 dramatically increased SOS1dependent Na ؉ tolerance, whereas SOS2 or SOS3 individually had no effect. The SOS2͞SOS3 kinase complex promoted the phosphorylation of SOS1. A constitutively active form of SOS2 phosphorylated SOS1 in vitro independently of SOS3, but could not fully substitute for the SOS2͞SOS3 kinase complex for activation of SOS1 in vivo. Further, we show that SOS3 recruits SOS2 to the plasma membrane. Although sos1 mutant plants display defective K ؉ uptake at low external concentrations, neither the unmodified nor the SOS2͞SOS3-activated SOS1 protein showed K ؉ transport capacity in vivo, suggesting that the role of SOS1 on K ؉ uptake is indirect. Our results provide an example of functional reconstitution of a plant response pathway in a heterologous system and demonstrate that the SOS1 ion transporter, the SOS2 protein kinase, and its associated Ca 2؉ sensor SOS3 constitute a functional module. We propose a model in which SOS3 activates and directs SOS2 to the plasma membrane for the stimulatory phosphorylation of the Na ؉ transporter SOS1.
El presente trabajo pretende ofrecer una experiencia de Musicoterapia realizada en el marco de un... more El presente trabajo pretende ofrecer una experiencia de Musicoterapia realizada en el marco de un Centro de Salud Mental. La Musicoterapia está incluída dentro de las actividades que realizan los pacientes del Hospital de día.
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Papers by Jose Pardo