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Sylvie Granon - One of the best experts on this subject based on the ideXlab platform.

  • individual differences in prefrontal cortical activation on the tower of london planning task implication for Effortful Processing
    European Journal of Neuroscience, 2003
    Co-Authors: F Cazalis, Romain Valabregue, Melanie Pelegriniissac, S Asloun, Trevor W Robbins, Sylvie Granon
    Abstract:

    Solving challenginxg ('Effortful') problems is known to involve the dorsal and dorsolateral prefrontal cortex in normal volunteers, although there is considerable individual variation. In this functional magnetic resonance imaging study, we show that healthy subjects with different levels of performance in the Tower of London planning task exhibit different patterns of brain activation. All subjects exhibited significant bilateral activation in the dorsolateral prefrontal cortex, the anterior and posterior cingulate areas and the parietal cortex. However, 'standard performers' (performance 70% correct) differed in the patterns of activation exhibited. Superior performers showed a significantly more spatially extended activation in the left dorsolateral prefrontal cortex than did standard performers, whereas the latter group tended to show increased activation of the anterior cingulate region.

  • Effortful information Processing in a spontaneous spatial situation by rats with medial prefrontal lesions
    Behavioural Brain Research, 1996
    Co-Authors: Sylvie Granon, Etienne Save, Marie-christine Buhot, Bruno Poucet
    Abstract:

    Previous research has suggested that the rat prefrontal cortex might play a role in spatial information Processing and in divided attention. More recent work showed that the effect of prefrontal lesions is more important when the task involves response selection in complex situations. The first aim of the present study was to test the effect of lesions of the prelimbic area of the rat prefrontal cortex in spatial exploration, a situation involving the Processing of spatial and non-spatial information, but requiring no response selection. The second aim was to manipulate the degree of cognitive effort required by the task. The latter effect was tested by manipulating the number of items to explore. Rats explored either a simple (3 objects) or a complex (6 objects) situation. We reasoned that acquiring spatial information so as to react adequately to spatial or non spatial changes involved more Effortful Processing in the complex situation than in the simpler one. The results suggest that the medial prefrontal cortex is not crucially involved in Effortful Processing when the task requires no response selection.

  • Nicotinic and muscarinic receptors in the rat prefrontal cortex: Differential roles in working memory, response selection and Effortful Processing
    Psychopharmacology, 1995
    Co-Authors: Sylvie Granon, Bruno Poucet, Catherine Thinus-blanc, Jean-pierre Changeux, C Vidal
    Abstract:

    The aim of the present study was to evaluate the effects of cholinergic receptor blockade in the rat prefrontal cortex on cognitive processes. The nicotinic antagonists neuronal bungarotoxin and dihydro- β -erythroidine and the muscarinic antagonist scopolamine were injected into the prelimbic area of the prefrontal cortex. Their behavioural effects were assessed in a T-maze to test reference memory (visual discrimination task) and working memory in delayed matching (MTS) and non-matching to sample (NMTS) tasks. Neuronal bungarotoxin produced a significant decrease in working memory performance in the MTS task but not in the NMTS task. In contrast, scopolamine impaired working memory in both MTS and NMTS tasks. Reference memory was not altered by any of the cholinergic antagonists. These results demonstrate a differential role of nicotinic and muscarinic receptors in the rat prefrontal cortex. Nicotinic transmission appears to be important in delayed response tasks requiring Effortful Processing for response selection, while the muscarinic system is involved in general working memory processes.

  • Working memory, response selection, and Effortful Processing in rats with medial prefrontal lesions
    Behavioral Neuroscience, 1994
    Co-Authors: Sylvie Granon, Catherine Thinus-blanc, Jean-pierre Changeux, Catherine Vidal, Bruno Poucet
    Abstract:

    This study examined the effects of lesions of the prelimbic area of the rat prefrontal cortex on acquisition and retention of nonmatching (NMTS) and matching-to-sample (MTS) tasks. Both tasks involved a reference and a working memory component, but only working memory was impaired by the lesions. A comparison of the 2 tasks revealed quantitatively similar deficits in postoperatively trained rats. In preoperatively trained rats, however, the deficits were more important in the MTS task than in the NMTS task. In addition, an effect of interference between successive trials was observed in the NMTS task but not in the MTS task. Perseverative tendencies were observed in the MTS task only. These results suggest that prefrontal lesions induce working memory deficits as a result of poor temporal encoding and increased susceptibility to interference and impair Effortful Processing, such as that engaged in response selection mechanisms.

Bruno Poucet - One of the best experts on this subject based on the ideXlab platform.

  • Effortful information Processing in a spontaneous spatial situation by rats with medial prefrontal lesions
    Behavioural Brain Research, 1996
    Co-Authors: Sylvie Granon, Etienne Save, Marie-christine Buhot, Bruno Poucet
    Abstract:

    Previous research has suggested that the rat prefrontal cortex might play a role in spatial information Processing and in divided attention. More recent work showed that the effect of prefrontal lesions is more important when the task involves response selection in complex situations. The first aim of the present study was to test the effect of lesions of the prelimbic area of the rat prefrontal cortex in spatial exploration, a situation involving the Processing of spatial and non-spatial information, but requiring no response selection. The second aim was to manipulate the degree of cognitive effort required by the task. The latter effect was tested by manipulating the number of items to explore. Rats explored either a simple (3 objects) or a complex (6 objects) situation. We reasoned that acquiring spatial information so as to react adequately to spatial or non spatial changes involved more Effortful Processing in the complex situation than in the simpler one. The results suggest that the medial prefrontal cortex is not crucially involved in Effortful Processing when the task requires no response selection.

  • Nicotinic and muscarinic receptors in the rat prefrontal cortex: Differential roles in working memory, response selection and Effortful Processing
    Psychopharmacology, 1995
    Co-Authors: Sylvie Granon, Bruno Poucet, Catherine Thinus-blanc, Jean-pierre Changeux, C Vidal
    Abstract:

    The aim of the present study was to evaluate the effects of cholinergic receptor blockade in the rat prefrontal cortex on cognitive processes. The nicotinic antagonists neuronal bungarotoxin and dihydro- β -erythroidine and the muscarinic antagonist scopolamine were injected into the prelimbic area of the prefrontal cortex. Their behavioural effects were assessed in a T-maze to test reference memory (visual discrimination task) and working memory in delayed matching (MTS) and non-matching to sample (NMTS) tasks. Neuronal bungarotoxin produced a significant decrease in working memory performance in the MTS task but not in the NMTS task. In contrast, scopolamine impaired working memory in both MTS and NMTS tasks. Reference memory was not altered by any of the cholinergic antagonists. These results demonstrate a differential role of nicotinic and muscarinic receptors in the rat prefrontal cortex. Nicotinic transmission appears to be important in delayed response tasks requiring Effortful Processing for response selection, while the muscarinic system is involved in general working memory processes.

  • Working memory, response selection, and Effortful Processing in rats with medial prefrontal lesions
    Behavioral Neuroscience, 1994
    Co-Authors: Sylvie Granon, Catherine Thinus-blanc, Jean-pierre Changeux, Catherine Vidal, Bruno Poucet
    Abstract:

    This study examined the effects of lesions of the prelimbic area of the rat prefrontal cortex on acquisition and retention of nonmatching (NMTS) and matching-to-sample (MTS) tasks. Both tasks involved a reference and a working memory component, but only working memory was impaired by the lesions. A comparison of the 2 tasks revealed quantitatively similar deficits in postoperatively trained rats. In preoperatively trained rats, however, the deficits were more important in the MTS task than in the NMTS task. In addition, an effect of interference between successive trials was observed in the NMTS task but not in the MTS task. Perseverative tendencies were observed in the MTS task only. These results suggest that prefrontal lesions induce working memory deficits as a result of poor temporal encoding and increased susceptibility to interference and impair Effortful Processing, such as that engaged in response selection mechanisms.

C Vidal - One of the best experts on this subject based on the ideXlab platform.

  • Nicotinic and muscarinic receptors in the rat prefrontal cortex: Differential roles in working memory, response selection and Effortful Processing
    Psychopharmacology, 1995
    Co-Authors: Sylvie Granon, Bruno Poucet, Catherine Thinus-blanc, Jean-pierre Changeux, C Vidal
    Abstract:

    The aim of the present study was to evaluate the effects of cholinergic receptor blockade in the rat prefrontal cortex on cognitive processes. The nicotinic antagonists neuronal bungarotoxin and dihydro- β -erythroidine and the muscarinic antagonist scopolamine were injected into the prelimbic area of the prefrontal cortex. Their behavioural effects were assessed in a T-maze to test reference memory (visual discrimination task) and working memory in delayed matching (MTS) and non-matching to sample (NMTS) tasks. Neuronal bungarotoxin produced a significant decrease in working memory performance in the MTS task but not in the NMTS task. In contrast, scopolamine impaired working memory in both MTS and NMTS tasks. Reference memory was not altered by any of the cholinergic antagonists. These results demonstrate a differential role of nicotinic and muscarinic receptors in the rat prefrontal cortex. Nicotinic transmission appears to be important in delayed response tasks requiring Effortful Processing for response selection, while the muscarinic system is involved in general working memory processes.

Linda Clare - One of the best experts on this subject based on the ideXlab platform.

  • learning face name associations in early stage dementia comparing the effects of errorless learning and Effortful Processing
    Neuropsychological Rehabilitation, 2007
    Co-Authors: Josephine Dunn, Linda Clare
    Abstract:

    Some recent studies suggest that errorless learning principles may be beneficial in memory rehabilitation for people with dementia, while others indicate that Effortful Processing may be more important. The present study compared the effects of four different learning techniques, varying in level of effort required and number of errors elicited, on free recall, cued recall and recognition of novel and previously known associations among people with early-stage dementia. Ten participants with a diagnosis of early-stage Alzheimer's, vascular or mixed dementia learned novel and previously familiar face–name associations with each of four techniques – vanishing cues, forward cues, target selection, and paired associate learning – in a within-subjects design. All conditions produced significant learning for both novel and familiar associations. There were no significant differences between conditions, although mean scores were slightly higher for errorful conditions. Reducing errors did not produce any benefit...

  • learning face name associations in early stage dementia comparing the effects of errorless learning and Effortful Processing
    Neuropsychological Rehabilitation, 2007
    Co-Authors: Josephine Dunn, Linda Clare
    Abstract:

    Some recent studies suggest that errorless learning principles may be beneficial in memory rehabilitation for people with dementia, while others indicate that Effortful Processing may be more important. The present study compared the effects of four different learning techniques, varying in level of effort required and number of errors elicited, on free recall, cued recall and recognition of novel and previously known associations among people with early-stage dementia. Ten participants with a diagnosis of early-stage Alzheimer's, vascular or mixed dementia learned novel and previously familiar face-name associations with each of four techniques--vanishing cues, forward cues, target selection, and paired associate learning--in a within-subjects design. All conditions produced significant learning for both novel and familiar associations. There were no significant differences between conditions, although mean scores were slightly higher for errorful conditions. Reducing errors did not produce any benefits. Enhancing level of effort had no significant effects for familiar associations, but high-effort conditions were significantly more effective than low-effort conditions in facilitating cued recall of novel associations. The results confirm that memory rehabilitation techniques can produce significant benefits, but do not support the view that error reduction during learning facilitates greater improvement in early-stage dementia. Effort enhancement may be more important, especially when learning novel associations.

Jean-pierre Changeux - One of the best experts on this subject based on the ideXlab platform.

  • Nicotinic and muscarinic receptors in the rat prefrontal cortex: Differential roles in working memory, response selection and Effortful Processing
    Psychopharmacology, 1995
    Co-Authors: Sylvie Granon, Bruno Poucet, Catherine Thinus-blanc, Jean-pierre Changeux, C Vidal
    Abstract:

    The aim of the present study was to evaluate the effects of cholinergic receptor blockade in the rat prefrontal cortex on cognitive processes. The nicotinic antagonists neuronal bungarotoxin and dihydro- β -erythroidine and the muscarinic antagonist scopolamine were injected into the prelimbic area of the prefrontal cortex. Their behavioural effects were assessed in a T-maze to test reference memory (visual discrimination task) and working memory in delayed matching (MTS) and non-matching to sample (NMTS) tasks. Neuronal bungarotoxin produced a significant decrease in working memory performance in the MTS task but not in the NMTS task. In contrast, scopolamine impaired working memory in both MTS and NMTS tasks. Reference memory was not altered by any of the cholinergic antagonists. These results demonstrate a differential role of nicotinic and muscarinic receptors in the rat prefrontal cortex. Nicotinic transmission appears to be important in delayed response tasks requiring Effortful Processing for response selection, while the muscarinic system is involved in general working memory processes.

  • Working memory, response selection, and Effortful Processing in rats with medial prefrontal lesions
    Behavioral Neuroscience, 1994
    Co-Authors: Sylvie Granon, Catherine Thinus-blanc, Jean-pierre Changeux, Catherine Vidal, Bruno Poucet
    Abstract:

    This study examined the effects of lesions of the prelimbic area of the rat prefrontal cortex on acquisition and retention of nonmatching (NMTS) and matching-to-sample (MTS) tasks. Both tasks involved a reference and a working memory component, but only working memory was impaired by the lesions. A comparison of the 2 tasks revealed quantitatively similar deficits in postoperatively trained rats. In preoperatively trained rats, however, the deficits were more important in the MTS task than in the NMTS task. In addition, an effect of interference between successive trials was observed in the NMTS task but not in the MTS task. Perseverative tendencies were observed in the MTS task only. These results suggest that prefrontal lesions induce working memory deficits as a result of poor temporal encoding and increased susceptibility to interference and impair Effortful Processing, such as that engaged in response selection mechanisms.