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Control Task (control + task)
Kinds of Control Task Selected AbstractsA shift from diffuse to focal cortical activity with developmentDEVELOPMENTAL SCIENCE, Issue 1 2006Sarah Durston Recent imaging studies have suggested that developmental changes may parallel aspects of adult learning in cortical activation becoming less diffuse and more focal over time. However, while adult learning studies examine changes within subjects, developmental findings have been based on cross-sectional samples and even comparisons across studies. Here, we used functional MRI in children to test directly for shifts in cortical activity during performance of a cognitive control task, in a combined longitudinal and cross-sectional study. Our longitudinal findings, relative to our cross-sectional ones, show attenuated activation in dorsolateral prefrontal cortical areas, paralleled by increased focal activation in ventral prefrontal regions related to task performance. [source] Functional specificity of human premotor,motor cortical interactions during action selectionEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 7 2007Jacinta O'Shea Abstract Functional connections between dorsal premotor cortex (PMd) and primary motor cortex (M1) have been revealed by paired-pulse transcranial magnetic stimulation (TMS). We tested if such connections would be modulated during a cognitive process (response selection) known to rely on those circuits. PMd,M1 TMS applied 75 ms after a cue to select a manual response facilitated motor-evoked potentials (MEPs). MEPs were facilitated at 50 ms in a control task of response execution, suggesting that PMd,M1 interactions at 75 ms are functionally specific to the process of response selection. At 100 ms, PMd,M1 TMS delayed choice reaction time (RT). Importantly, the MEP (at 75 ms) and the RT (at 100 ms) effects were correlated in a way that was hand-specific. When the response was made with the M1-contralateral hand, MEPs correlated with slower RTs. When the response was made with the M1-ipsilateral hand, MEPs correlated with faster RTs. Paired-pulse TMS confined to M1 did not produce these effects, confirming the causal influence of PMd inputs. This study shows that a response selection signal evolves in PMd early during the reaction period (75,100 ms), impacts on M1 and affects behaviour. Such interactions are temporally, anatomically and functionally specific, and have a causal role in choosing which movement to make. [source] The essential role of Broca's area in imitationEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 5 2003Marc Heiser Abstract The posterior sector of Broca's area (Brodmann area 44), a brain region critical for language, may have evolved from neurons active during observation and execution of manual movements. Imaging studies showing increased Broca's activity during execution, imagination, imitation and observation of hand movements support this hypothesis. Increased Broca's activity in motor task, however, may simply be due to inner speech. To test whether Broca's area is essential to imitation, we used repetitive transcranial magnetic stimulation (rTMS), which is known to transiently disrupt functions in stimulated areas. Subjects imitated finger key presses (imitation) or executed finger key presses in response to spatial cues (control task). While performing the tasks, subjects received rTMS over the left and right pars opercularis of the inferior frontal gyrus (where Brodmann area 44 is probabilistically located) and over the occipital cortex. There was significant impairment in imitation, but not in the control task, during rTMS over left and right pars opercularis compared to rTMS over the occipital cortex. This suggests that Broca's area is a premotor region essential to finger movement imitation. [source] Direction of cross-modal information transfer affects human brain activation: a PET studyEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 1 2002Ryuta Kawashima Abstract The purpose of this study was to determine the functional organization of the human brain involved in cross-modal discrimination between tactile and visual information. Regional cerebral blood flow was measured by positron emission tomography in nine right-handed volunteers during four discrimination tasks; tactile,tactile (TT), tactile,visual (TV), visual,tactile (VT), and visual,visual (VV). The subjects were asked either to look at digital cylinders of different diameters or to grasp the digital cylinders with the thumb and index finger of the right hand using haptic interfaces. Compared with the motor control task in which the subjects looked at and grasped cylinders of the same diameter, the right lateral prefrontal cortex and the right inferior parietal lobule were activated in all the four discrimination tasks. In addition, the dorsal premotor cortex, the ventral premotor cortex, and the inferior temporal cortex of the right hemisphere were activated during VT but not during TV. Our results suggest that the human brain mechanisms underlying cross-modal discrimination have two different pathways depending on the temporal order in which stimuli are presented. [source] Differential patterns of cortical activation as a function of fluid reasoning complexityHUMAN BRAIN MAPPING, Issue 2 2009Bernardo Perfetti Abstract Fluid intelligence (gf) refers to abstract reasoning and problem solving abilities. It is considered a human higher cognitive factor central to general intelligence (g). The regions of the cortex supporting gf have been revealed by recent bioimaging studies and valuable hypothesis on the neural correlates of individual differences have been proposed. However, little is known about the interaction between individual variability in gf and variation in cortical activity following task complexity increase. To further investigate this, two samples of participants (high-IQ, N = 8; low-IQ, N = 10) with significant differences in gf underwent two reasoning (moderate and complex) tasks and a control task adapted from the Raven progressive matrices. Functional magnetic resonance was used and the recorded signal analyzed between and within the groups. The present study revealed two opposite patterns of neural activity variation which were probably a reflection of the overall differences in cognitive resource modulation: when complexity increased, high-IQ subjects showed a signal enhancement in some frontal and parietal regions, whereas low-IQ subjects revealed a decreased activity in the same areas. Moreover, a direct comparison between the groups' activation patterns revealed a greater neural activity in the low-IQ sample when conducting moderate task, with a strong involvement of medial and lateral frontal regions thus suggesting that the recruitment of executive functioning might be different between the groups. This study provides evidence for neural differences in facing reasoning complexity among subjects with different gf level that are mediated by specific patterns of activation of the underlying fronto-parietal network. Hum Brain Mapp, 2009. © 2007 Wiley-Liss, Inc. [source] Biphasic hemodynamic responses influence deactivation and may mask activation in block-design fMRI paradigmsHUMAN BRAIN MAPPING, Issue 4 2008Jed A. Meltzer Abstract A previous block-design fMRI study revealed deactivation in the hippocampus in the transverse patterning task, specifically designed, on the basis of lesion literature, to engage hippocampal information processing. In the current study, a mixed block/event-related design was used to determine the temporal nature of the signal change leading to the seemingly paradoxical deactivation. All positive activations in the hippocampal-dependent condition, relative to a closely matched control task, were seen to result from positive BOLD transients in the typical 4,7 s poststimulus time range. However, most deactivations, including in the hippocampus and in other "default mode" regions commonly deactivated in cognitive tasks, were attributable to enhanced negative transient signals in a later time range, 10,12 s. This late hemodynamic transient was most pronounced in medial prefrontal cortex. In some regions, the hippocampal-dependent condition enhanced both the early positive and late negative transients to approximately the same degree, resulting in no significant signal change when block analysis is used, despite very different event-related responses. These results imply that delayed negative transients can play a role in determining the presence and sign of brain activation in block-design studies, in which case an event-related analysis can be more sensitive than a block analysis, even if the different conditions occur within blocks. In this case, default mode deactivations are timelocked to stimulus presentation as much as positive activations are, but in a later time range, suggesting a specific role of negative transient signals in task performance. Hum Brain Mapp, 2008. © 2007 Wiley-Liss, Inc. [source] On an output-feedback stabilization problem with uncertainty in the relative degreeINTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL, Issue 7 2008Giorgio Bartolini Abstract This paper deals with an output-feedback finite-time control problem for a class of nonlinear uncertain systems whose relative degree is affected by an uncertain system parameter and is therefore unknown at the stage of control design. We show that an existing second-order sliding mode control algorithm can address successfully the control task of a finite-time output-feedback stabilization when the uncertain relative degree is equal to 1 or 2. We derive constructive tuning rules for the control parameters and show its effectiveness by using computer simulations. Copyright © 2007 John Wiley & Sons, Ltd. [source] Reduced right hemisphere activation in severely abused violent offenders during a working memory task: An fMRI studyAGGRESSIVE BEHAVIOR, Issue 2 2001Adrian Raine Abstract This study uses functional magnetic resonance imaging (fMRI) to address two important gaps in our knowledge of brain functioning and violence: (1) What are the brain correlates of adults in the community who have suffered severe physical abuse early in life and who go on to perpetrate serious violence in adulthood? (2) What characterizes those who experience severe physical abuse but who refrain from serious violence? Four groups of participants recruited from the community (controls, severe physical child abuse only, serious violence only, and severely abused, seriously violent offenders) underwent fMRI while performing a visual/verbal working memory task. Violent offenders who had suffered severe child abuse show reduced right hemisphere functioning, particularly in the right temporal cortex. Abused individuals who refrain from serious violence showed relatively lower left, but higher right, activation of the superior temporal gyrus. Abused individuals, irrespective of violence status, showed reduced cortical activation during the working memory task, especially in the left hemisphere. Brain deficits were independent of IQ, history of head injury, task performance, cognitive strategy, and mental activity during the control task. Findings constitute the first fMRI study of brain dysfunction in violent offenders, and indicate that initial right hemisphere dysfunction, when combined with the effects of severe early physical abuse, predisposes to serious violence but that relatively good right hemisphere functioning protects against violence in physically abused children. Aggr. Behav. 27:111,129, 2001. © 2001 Wiley-Liss, Inc. [source] Language dominance assessment by means of fMRI: Contributions from task design, performance, and stimulus modalityJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 5 2001Margret Hund-Georgiadis MD Abstract We investigated the influence of different task demands, task designs, and presentation modalities on the functional MRI activation patterns during a language lateralization task in a group of 14 right-handed control subjects. A word classification task was presented as target task appropriate to evoke language-related activation in the inferior frontal gyrus (IFG). The choice of the contrasting baseline task was demonstrated to have a major impact on the functional outcome: While a fixation baseline elicited activations in the inferior frontal gyrus of both hemispheres, a nonsemantic perceptual control task helped to isolate the relevant target task of word classification. The modality of stimulus presentation did not influence the functional data: Auditory and visual presentation modes broadly evoked activations in similar brain regions during word classification. Minor differences in task performance and the side of the responding hand did not interfere with the functional activation patterns of the target task. On the basis of our results, a protocol of functional lateralization in the inferior frontal gyrus is suggested. J. Magn. Reson. Imaging 2001;13:668,675. © 2001 Wiley-Liss, Inc. [source] Functional Magnetic Resonance Imaging of Working Memory among Multiple Sclerosis PatientsJOURNAL OF NEUROIMAGING, Issue 2 2004Lawrence H. Sweet PhD ABSTRACT Background and Purpose. Verbal working memory (VWM) deficits have been a well-replicated finding among patients with multiple sclerosis (MS). Functional magnetic resonance imaging (FMRI) studies have described a VWM system in healthy samples; however, functional neuroimaging of this system among MS patients is just beginning to appear. Methods. Fifteen MS patients and 15 sex-, age-, education-, and IQ-matched healthy control (HC) participants completed a 2-Back VWM task as whole-brain FMRI was conducted. Results. Each group exhibited increased brain activity compared to the 0-Back control task in regions associated with the 2-Back in previous neuroimaging studies. These included Broca's area, supplementary motor area (SMA), premotor cortices (PMC), and dorsolateral prefrontal cortices (DLPFC). MS patients exhibited greater cortical activity than did HC participants in left primary motor and somatosensory cortices, PMC, DLPFC, anterior cingulate, and bilateral SMA. MS patients exhibited relatively less activation in Broca's area, bilateral cerebellum, and other regions not typically associated with the 2-Back (eg, right fusiform gyrus, left lingual gyrus, right hippocampus). Performance accuracy and reaction time did not differ between groups. Conclusions. Normal performance of a challenging VWM task among high-functioning MS patients is associated with a shift toward greater activity in regions related to sensorimotor functions and anterior attentional/executive components of the VWM system. Posterior memory storage systems appeared unaffected, while portions of the visual processing and subvocal rehearsal systems were less active. Although a shift in neural activity was noted relative toHC participants, deviation from regions normally involved in VWM function was not observed in this patient sample. [source] Action monitoring in motor control: ERPs following selection and execution errors in a force production taskPSYCHOPHYSIOLOGY, Issue 5 2003Ellen R. A. De Bruijn Abstract Action monitoring has been studied in many tasks by means of measuring the error-related negativity (Ne/ERN), but never in a motor control task requiring precise force production. Errors in discrete choice reaction tasks are the result of incorrect selections, but errors in force production can also arise from incorrect executions. ERPs were obtained while participants produced low or high isometric forces with their left or right hand. As expected, incorrect choices of hand elicited an Ne/ERN. Interestingly, Ne/ERNs were also present in the less discrete selection error of an incorrect choice of force, but only when erroneously a low instead of a high force was chosen. In both force ranges, no Ne/ERNs were found after errors in execution. These errors showed a large positivity in feedback ERPs and, similar to correct responses, a prolonged negativity in response ERPs. We propose that, compared to selection errors, the time uncertainty aspects of execution errors and the resulting changing response representations prohibit error detection by the internal monitoring system responsible for generating the Ne/ERN. [source] Cognitive and emotional modulation of the cardiac defense response in humansPSYCHOPHYSIOLOGY, Issue 3 2000María Nieves Pérez The cognitive and emotional modulation of the cardiac defense response was investigated in this study. One hundred forty-four participants were exposed to three presentations of an intense auditory stimulus while performing one of four attentional tasks: a control task, an external perceptual tracking task, and two internal tasks presented at either easy or difficult memory loads. State anxiety was also manipulated by requiring each group to perform either with or without the threat of shock. Heart rate and vasomotor activity were recorded. Results indicated that only the externally directed tracking task led to potentiation of the cardiac response. No predicted effects for attentional demands were obtained and the anxiety manipulation did not appear to have an effect. Differences between measures were also observed, particularly with respect to response habituation. Unlike cardiac activity, vasomotor responses displayed resistance to habituation. The results are discussed in relation to contemporary accounts of defensive responding. [source] Articulatory suppression attenuates the verbal overshadowing effect: a role for verbal encoding in face identificationAPPLIED COGNITIVE PSYCHOLOGY, Issue 2 2006Lee H. V. Wickham Verbal overshadowing is the phenomenon that verbally describing a face between presentation and test can impair identification of the face (Schooler & Engstler-Schooler, 1990). This study examined the effects of articulatory suppression and distinctiveness upon the magnitude of the verbal overshadowing effect. Participants engaged in articulatory suppression or a control task whilst viewing a target face. They then either described the face or completed a distractor task before selecting the target face from a line-up. This was repeated for 12 trials. Articulatory suppression impaired identification performance overall, and reduced the negative effects of description to non-significance, whereas the control group demonstrated the standard verbal overshadowing effect. Typical faces showed verbal overshadowing, whereas distinctive faces did not. These results are consistent with the view that verbal overshadowing arises because the description of the target face creates a verbal code that interferes with a verbal code created spontaneously during encoding. Copyright © 2006 John Wiley & Sons, Ltd. [source] The effects of verbalization on face recognition in young and older adultsAPPLIED COGNITIVE PSYCHOLOGY, Issue 6 2002Amina Memon To explore the forensic implications of ,verbal overshadowing' in young and older eyewitnesses, we examined the effects of providing a verbal face description on subsequent performance in a lineup task. Young (18,30 years) and older (60,80 years) adults viewed a videotaped crime and performed some unrelated cognitive tasks. Participants in the experimental condition were then asked to supply a description of the target person in the event or to perform a control task. Upon completing the description/control task participants attempted to identify the target person from a target present photo-lineup presented in a sequential or simultaneous mode. Older participants made more false choices and sequential testing reduced correct choices. There was a weak trend consistent with verbal overshadowing that was unrelated to age as well as measures of verbal and face-matching expertise. Although overshadowing reduced performance only slightly, it appeared to affect the self-reported use of a feature-matching strategy linked to accurate decisions by young adults and inaccurate decisions by senior adults. Copyright © 2002 John Wiley & Sons, Ltd. [source] Enforcement of environmental charges: some economic aspects and evidence from the German Waste Water ChargeENVIRONMENTAL POLICY AND GOVERNANCE, Issue 5 2001Professor Dr Erik Gawel Enforcement problems are usually analysed with respect to command-and-control measures of environmental regulation. The recognition that any environmental policy instrument entails an enforcement problem in principle is basic to a comparative analysis of enforcement effects. This paper deals with the comparative enforcement effects of charges: How does enforcement of a charge function? Which problems occur particularly in the enforcement of charges? Could enforcement be facilitated by a specific construction of charge laws? Are economic concepts of charge enforceable at all, and if so, under what conditions? Are charges more readily enforceable than other instruments? Therefore, some economic theory assessments of enforcement processes are presented first. In a third part, the paper sheds light on the practical experience made with the enforcement of the German Waste Water Charge. It is argued that the well worn thesis of an enforcement-friendly ,self-control' of market instruments is based on unrealistic assumptions. Whether against this background enforcement of environmental policy can be facilitated by an increased application use of charges must be viewed sceptically in an overall assessment of the problematic. Moreover, the transition from allocative control tasks to fiscal environmental charges may well be a symptom of rather than a contribution to the solution of the political and administrative crisis of enforcement. Especially for charges, the crucial question seems to be the political implementation rather than concrete enforcement by local authorities. Copyright © 2001 John Wiley & Sons, Ltd. and ERP Environment [source] How specific is the relation between executive function and theory of mind?INFANT AND CHILD DEVELOPMENT, Issue 2 2002Contributions of inhibitory control, working memory Abstract The relation between executive function (EF) and theory of mind (ToM) may involve specific processes of inhibition and/or working memory capacity contributing to ToM, or it might be a reflection of general intellectual ability. To differentiate these alternatives, we administered task batteries measuring inhibitory control (IC), working memory, and ToM, as well as measures of verbal and performance intelligence, to 47 typically developing preschool children. Inhibitory control tasks in which a dominant response needed to be suppressed while a subdominant response was activated (Conflict IC) significantly predicted performance on false belief tasks over and above working memory, the intelligence measures, a simple delay task (Delay IC), and age. In contrast, working memory, Delay IC, and intelligence were not significant in this analysis. Conflict IC, but not Delay IC, was related to working memory. Together, these findings suggest that the combination of inhibition and working memory (as reflected in Conflict IC tasks) may be central to the relation between EF and false belief understanding. Copyright © 2002 John Wiley & Sons, Ltd. [source] Online trained support vector machines-based generalized predictive control of non-linear systemsINTERNATIONAL JOURNAL OF ADAPTIVE CONTROL AND SIGNAL PROCESSING, Issue 10 2006S. Iplikci Abstract In this work, an online support vector machines (SVM) training method (Neural Comput. 2003; 15: 2683,2703), referred to as the accurate online support vector regression (AOSVR) algorithm, is embedded in the previously proposed support vector machines-based generalized predictive control (SVM-Based GPC) architecture (Support vector machines based generalized predictive control, under review), thereby obtaining a powerful scheme for controlling non-linear systems adaptively. Starting with an initially empty SVM model of the unknown plant, the proposed online SVM-based GPC method performs the modelling and control tasks simultaneously. At each iteration, if the SVM model is not accurate enough to represent the plant dynamics at the current operating point, it is updated with the training data formed by persistently exciting random input signal applied to the plant, otherwise, if the model is accepted as accurate, a generalized predictive control signal based on the obtained SVM model is applied to the plant. After a short transient time, the model can satisfactorily reflect the behaviour of the plant in the whole phase space or operation region. The incremental algorithm of AOSVR enables the SVM model to learn the new training data pair, while the decremental algorithm allows the SVM model to forget the oldest training point. Thus, the SVM model can adapt the changes in the plant and also in the operating conditions. The simulation results on non-linear systems have revealed that the proposed method provides an excellent control quality. Furthermore, it maintains its performance when a measurement noise is added to the output of the underlying system. Copyright © 2006 John Wiley & Sons, Ltd. [source] A review of current developments in process and quality control for injection moldingADVANCES IN POLYMER TECHNOLOGY, Issue 3 2005Zhongbao Chen Abstract Injection molding is one of the most versatile and important manufacturing processes capable of mass-producing complicated plastic parts in net shape with excellent dimensional tolerance. Injection molding process and quality control has been an active research area for many years, as part quality and yield requirements become more stringent. This paper reviews the state-of-the-art research and development in injection molding control. It organizes prior studies into four categories, namely, process setup, machine control, process control, and quality control, and presents the distinction and connection of these different levels of control. This paper further reviews and compares the typical variables, models, and control methods that have been proposed and employed for those control tasks. Strictly speaking, real online quality control without human intervention has yet to be realized, primarily due to the lack of transducers for online, real time quality response measurement, and a robust model that correlates the control variables with quantitative quality measurements. Based on the research progress to date, this paper suggests that the different levels of control tasks have to be integrated into a multilevel quality control system, and that the quality sensor and the process and quality model are the two most important areas for further advancement in injection molding control. © 2005 Wiley Periodicals, Inc. Adv Polym Techn 24: 165,182, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.20046 [source] Cognitive deficits in narcolepsyJOURNAL OF SLEEP RESEARCH, Issue 3 2006A. NAUMANN Summary The aim of the investigations was to explore the nature and the severity of cognitive deficits in narcolepsy patients. In two studies, narcolepsy patients were compared with matched control subjects on a range of attention, memory and executive control tasks. Impairments were only observed on attention and executive function tasks which involved higher demands on inhibition or task management abilities whereas relatively routine memory and attention tasks yielded intact performance in narcolepsy patients. The overall pattern of results indicates an executive control deficit in narcolepsy which might be related to a reduction of available cognitive processing resources because of the need for continuous allocation of resources to monitoring and maintenance of vigilance. [source] Low- and high-level controlled processing in executive motor control tasks in 5,6-year-old children at risk of ADHDTHE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 7 2003Ariane C. Kalff Background: The scant research on the characteristics of Attention-Deficit/Hyperactivity Disorder (ADHD) in kindergarten years curtails progress on early assessment of ADHD. Method: By screening a general population sample of 1317 five- to six-year-old children, four groups of children were selected. The performance of 30 children later diagnosed with ADHD was compared with 74 children later diagnosed with ,borderline ADHD' (children exhibiting all ADHD symptoms but without disruptions on two situations), 113 children later diagnosed with other psychopathology, and 126 healthy controls on computerised motor control tasks involving low- and high-level controlled processing. In addition, motor control was compared with movement speed. Results: The children at risk of ADHD were in general less accurate and more variable in their movements than the children with other psychopathology and healthy controls. Under conditions of high-level controlled processing, the children at risk of ADHD were disproportionately more inaccurate and had a more unstable performance with their preferred hand than the other children. In addition, linear effects were found, with the children at risk of ADHD having the worst performance, followed by the children with ,borderline ADHD', and then both groups of control children. No significant group differences were found in movement speed. Conclusions: The main findings are interpreted as evidence for a specific deficit in high-level controlled processing in young children at risk of ADHD, now found in a motor task, rather than a response task. Furthermore, the results support the notion that ADHD represents a dimensional trait. In addition, problems in movement control (the need to allocate attentional capacity) rather than problems in movement speed distinguish children at risk of ADHD from other children. The findings are interpreted as evidence that higher-order executive processes, such as self-control and self-regulation, are already affected early in the development of ADHD. [source] The graphemic/motor frontal area Exner's area revisited,ANNALS OF NEUROLOGY, Issue 4 2009Franck-Emmanuel Roux MD Objective In 1881, Exner first described a "graphic motor image center" in the middle frontal gyrus. Current psycholinguistic models of handwriting involve the conversion of abstract, orthographic representations into motor representations before a sequence of appropriate hand movements is produced. Direct cortical stimulation and functional magnetic resonance imaging (fMRI) were used to study the human frontal areas involved in writing. Methods Cortical electrical stimulation mapping was used intraoperatively in 12 patients during the removal of brain tumors to identify the areas involved in oral language (sentence reading and naming) and writing, and to spare them during surgery. The fMRI activation experiment involved 12 right-handed and 12 left-handed healthy volunteers using word dictation (without visual control) and 2 control tasks. Results Direct cortical electrical stimulation of restricted areas rostral to the primary motor hand area (Brodmann area [BA] 6) impaired handwriting in 6 patients, without disturbing hand movements or oral language tasks. In 6 other patients, stimulation of lower frontal regions showed deficits combining handwriting with other language tasks. fMRI also revealed selective activation during word handwriting in left versus right BA6 depending on handedness. This area was anatomically matched to those areas that affected handwriting on electrical stimulation. Interpretation An area in middle frontal gyrus (BA6) that we have termed the graphemic/motor frontal area supports bridging between orthography and motor programs specific to handwriting. Ann Neurol 2009;66:537,545 [source] The Impact of Internal Auditor Compensation and Role on External Auditors' Planning Judgments and Decisions,CONTEMPORARY ACCOUNTING RESEARCH, Issue 2 2001F. Todd Dezoort Abstract This paper reports the results of an experiment that investigates how external audit planning is affected when internal auditors have incentives and the opportunity to bias their evaluations. Specifically, we draw on attribution theory to examine how internal auditor eligibility for incentive compensation and participation in consulting (i.e., two factors that provide incentives to bias audit evaluations) affect external audit planning. In addition, we examine the effects of incentive compensation and a consulting role across two routine internal audit tasks , an objective tests of controls task and a subjective inventory valuation task , to evaluate whether their effects are contingent upon task subjectivity (i.e., opportunity to bias audit evaluations). Seventy-six external auditors from four Big 5 public accounting firms participated in an experiment that manipulated internal auditor compensation (fixed salary versus incentive compensation), the type of work that the internal auditors routinely perform (primarily auditing versus primarily consulting), and audit task subjectivity (objective tests of controls versus subjective inventory valuation). Our results suggest that the nature of internal auditors' compensation and work affect audit planning recommendations differently. The opportunity to receive incentive compensation results in less reliance on internal auditors' work and greater budgeted audit hours, but only for the subjective task. Although a consulting role decreases perceived internal auditor objectivity, it has a limited effect on planning recommendations. Specifically, consulting has no effect on reliance, and leads to greater budgeted audit hours only when incentive compensation is available. We discuss potential explanations for the results as well as implications for audit research, practice, and regulation. [source] | ||||||||||||||||||||||||||||||||||