44 research outputs found

    Apraxia of tool use: more evidence for the technical reasoning hypothesis

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    Various distinct cognitive processes such as semantic memory, executive planning or technical reasoning have been shown to support tool use. The aim of this study is to investigate the relationship between these processes. To do so, a large apraxia battery was submitted to 16 patients with left brain-damage (LBD) and aphasia and 19 healthy controls. The battery included: classical apraxia tests (Pantomime of Tool Use and Single Tool Use), familiar and novel tool use tests (Tool-Object Pairs and Sequential Mechanical Problem-Solving), semantic memory tests (Recognition of tool utilization gestures and Functional and Categorical Associations) as well as the Tower Of London. The Sequential Mechanical Problem-Solving task is a new task which permits the evaluation of pre-planning in unusual tool use situations. In this task as well as in the Tool-Object Pairs task, participants solved a tool use problem in a Choice and a No-Choice condition to examine the effect of tool selection. Globally, left brain damaged patients were impaired as compared to controls. We found high correlations in left brain damaged patients between performances on classical apraxia tests, familiar and novel tool use tests and Functional and Categorical Associations but no significant association between these performances and Tower Of London or Recognition of tool utilization gestures. Furthermore, the two conditions (Choice and No-Choice) of Tool-Object Pairs and Sequential Mechanical Problem-Solving were associated. In sum, all tasks involving tool use are strongly associated in LBD patients. Moreover, the ability to solve sequential mechanical problems does not depend on executive planning. Also, tool use appears to be associated with knowledge about object function but not with knowledge about tool manipulation. Taken together, these findings indicate that technical reasoning and, to a lesser extent, semantic memory may both play an important role in tool use

    Frontal versus dysexecutive syndromes: relevance of an interactionist approach in a case series of patients with prefrontal lobe damage

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    The concepts of "frontal" and "dysexecutive" syndromes are still a matter of debate in the literature. These terms are often used interchangeably but can be distinguished when considering specific frontal behavioural deficits which occur during social interaction. Despite being of interest for the clinical assessment and care management of patients with anterior brain damage, few studies have tried to disentangle the specificity of each syndrome. We report the case of eight patients with frontal lobe damage who were assigned to one of two groups based on whether or not they showed a dysexecutive syndrome. The nondysexecutive group differed from the dysexecutive group in showing environmental dependency phenomena, behavioural disorders triggered by social interaction. By adopting an interactionist perspective, this pilot study contributes to defining more precisely the distinction between "frontal" and "dysexecutive" syndromes. The discussion focuses on the potential interest of the interactionist approach in designing appropriate methodologies of assessment and rehabilitation of patients with frontal lobe syndrome

    An integrative view of Luria’s perspective on arithmetic problem solving: The two sides of environmental dependency

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    INTRODUCTION: A. R. Luria was the first author to hypothesize that executive dysfunction can lead to specific deficits in arithmetic problem solving, showing that patients\u27 performance depends on the structure of the tasks. Cummings (1995. Anatomic and behavioral aspects of frontal-subcortical circuits. Annals of the New York Academy of Sciences, 15, 1-13) proposed the term "environmental dependency" to define such behavioral disorders triggered by the characteristics of the test and pointed out also the role of executive impairments. Few studies compare executive functioning and problem solving in brain-damaged patients, and none have examined the question from this point of view. Thus, the main aim of the present paper was to study the relationship between environmental dependency and executive functions. METHOD: Fifty neurological patients with frontal, subcortical, and posterior brain lesions were compared to 45 matched healthy controls and were divided into two groups (dysexecutive/nondysexecutive) according to their performances on executive tasks. Then, we confronted the results of the two groups on an experimental protocol designed in accordance with Luria\u27s proposals. We made also comparisons between groups on the basis of lesion location. RESULTS: Our findings indicate a high association between executive functions and environmental dependency, showing that dysexecutive patients\u27 performances were dependent on task demands. In addition, a specific frontal behavior not associated with executive functions and characterized by the solving of insoluble problems was highlighted. CONCLUSION: The discussion focused on the interest to take into account the methodological and clinical contributions of environmental dependency. Based on our findings and theoretical arguments, we highlight the need to fractionate this concept

    Decision-making of Prefrontal Patients with the Iowa Gambling Task: Unexpected Spared Performances and Preliminary Evidence for the Need of Alternative Measures

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    Objective. Human decision-making is a growing area of research most commonly associated with the Iowa Gambling Task (IGT), which was first developed to assess patients with prefrontal cortex (PFC) damage. The IGT is now considered an appropriate task to predict behavioral disorders in various clinical populations. However, several studies have questioned the validity and reliability of the task, arguing that its particular payoff scheme may influence the decision-making process in terms of sensitivity to gain-loss frequency (GLF) rather than long-term outcome (the basic assumption of IGT). Despite the potential significance of this assertion for the diagnosis of decision-making deficits, few studies have addressed the influence of GLF on IGT performances in clinical populations, and there is no study to date that involves patients with prefrontal lobe damage. Method. We tested 17 patients with PFC damage and 17 matched healthy controls with the IGT to analyze influence in choice behavior of both long-term outcomes and GLF. Results. There was a difference between groups in the GLF score, but none between groups in the long-term outcome variable (the traditional measure). Our findings demonstrate that only control subjects seemed able to consider both long-term outcome and GLF. Conclusions. The discussion focuses on the contribution of empirical data, which may have implications for the clinical assessment of decision-making ability with the IGT

    Mechanical problem-solving and imitation of meaningless postures in left brain damaged patients: Two sides of the same coin?

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    Left brain damaged (LBD) patients with difficulties to use familiar tools are also impaired when asked to use novel tools to solve mechanical problems (Goldenberg and Hagmann, 1998, Goldenberg and Spatt, 2009, Hartmann et al., 2005, Jarry et al., 2013, Osiurak et al., 2009 and Osiurak et al., 2013). These patients have been suggested to be unable to reason about the mechanical properties of tools and objects, whether they are familiar or novel (i.e., the technical reasoning hypothesis; Jarry et al., 2013). Goldenberg, 2009 and Goldenberg, 2013 has formulated a somewhat similar view in his spatial, categorical apprehension hypothesis. For him, tool use is based on the ability to configure a whole chain of mechanical relationships between multiple objects or multiple parts of objects. Importantly, this spatial, categorical apprehension can also be applied to the human body, considered as a multi-part mechanical object. In this framework, Goldenberg, 2009 and Goldenberg, 2013 has argued that, in LBD patients, difficulties in both tool use and imitation of meaningless postures (IMP) (particularly hand postures) might be two manifestations of the same disorder. Therefore, according to the spatial, categorical apprehension hypothesis, a strong link should be observed between the use of familiar tools, mechanical problem-solving, and IMP. No study so far has tested this prediction within the same group of LBD patients. So, our aim was to fill this gap by exploring the relationships between the use of familiar tools (i.e., Tool-Object Pairs (TOP)), mechanical problem-solving, and IMP in 17 LBD patients. [...

    Tool use in left brain damage and Alzheimer's disease: What about function and manipulation knowledge?

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    Tool use disorders are usually associated with difficulties in retrieving function and manipulation knowledge. Here, we investigate tool use (Real Tool Use, RTU), function (Functional Association, FA) and manipulation knowledge (Gesture Recognition, GR) in 17 left-brain-damaged (LBD) patients and 14 AD patients (Alzheimer disease). LBD group exhibited predicted deficit on RTU but not on FA and GR while AD patients showed deficits on GR and FA with preserved tool use skills. These findings question the role played by function and manipulation knowledge in actual tool use

    Rethinking the Cognitive Mechanisms Underlying Pantomime of Tool Use: Evidence from Alzheimer's Disease and Semantic Dementia

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    OBJECTIVES: Pantomiming the use of familiar tools is a central test in the assessment of apraxia. However, surprisingly, the nature of the underlying cognitive mechanisms remains an unresolved issue. The aim of this study is to shed a new light on this issue by exploring the role of functional, mechanical, and manipulation knowledge in patients with Alzheimer\u27s disease and semantic dementia and apraxia of tool use. METHODS: We performed multiple regression analyses with the global performance and the nature of errors (i.e., production and conception) made during a pantomime of tool use task in patients and control participants as dependent variables and tasks investigating functional, mechanical, and manipulation knowledge as predictors. RESULTS: We found that mechanical problem solving, assessing mechanical knowledge, was a good predictor of the global performance of pantomime of tool use. We also found that occurrence of conception errors was robustly predicted by the task assessing functional knowledge whereas that of production errors was not explained by only one predictor. CONCLUSIONS: Our results suggest that both functional and mechanical knowledge are important to pantomime the use of tools. To our knowledge, this is the first demonstration that mechanical knowledge plays a role in pantomime of tool use. Although impairment in pantomime of tool use tasks (i.e., apraxia) is widely explained by the disruption of manipulation knowledge, we propose that pantomime of tool use is a complex problem-solving task. (JINS, 2017, 23, 128-138)

    Presumed Symbolic Use of Diurnal Raptors by Neanderthals

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    In Africa and western Eurasia, occurrences of burials and utilized ocher fragments during the late Middle and early Late Pleistocene are often considered evidence for the emergence of symbolically-mediated behavior. Perhaps less controversial for the study of human cognitive evolution are finds of marine shell beads and complex designs on organic and mineral artifacts in early modern human (EMH) assemblages conservatively dated to ≈100–60 kilo-years (ka) ago. Here we show that, in France, Neanderthals used skeletal parts of large diurnal raptors presumably for symbolic purposes at Combe-Grenal in a layer dated to marine isotope stage (MIS) 5b (≈90 ka) and at Les Fieux in stratigraphic units dated to the early/middle phase of MIS 3 (60–40 ka). The presence of similar objects in other Middle Paleolithic contexts in France and Italy suggest that raptors were used as means of symbolic expression by Neanderthals in these regions

    Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences

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    The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & Nemésio 2007; Donegan 2008, 2009; Nemésio 2009a–b; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on 18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based researchers who signed it in the short time span from 20 September to 6 October 2016
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