Behavioral and neural correlates of performance feedback in younger and older adults Von der Medizinischen Fakultät der Rheinisch-Westfälischen Technischen Hochschule Aachen zur Erlangung des akademischen Grades einer Doktorin der Theoretischen Medizin genehmigte Dissertation vorgelegt von Dipl.-Psych. Lydia Beck aus Köln Berichter: Herr Universitätsprofessor Dr.phil. Dipl.-Psych. Siegfried Gauggel Herr Professor Dr.rer.nat. Dipl.-Psych. Walter Sturm Tag der mündlichen Prüfung: 8. November 2010 Diese Dissertation ist auf den Internetseiten der Hochschulbibliothek online verfügbar. Lydia Beck – Performance feedback in younger and older adults Table of contents 1 General Introduction 1 2 Study One: Effects of performance feedback on executive control in younger and older adults 3 2.1 Introduction 3 2.2 Experiment 1: Feedback effect in younger adults 5 2.2.1 Introduction 5 2.2.2 Method 6 2.2.3 Results 9 2.2.4 Discussion 10 2.3 Experiment 2: Feedback effect in older adults 12 2.3.1 Introduction 12 2.3.2 Method 13 2.3.3 Results 14 2.3.4 Discussion 15 2.4 General Discussion 17 3 Study Two: Neural correlates of positive and negative performance feedback in younger and older adults 21 3.1 Introduction 21 3.2 Method 22 3.2.1 Participants 22 3.2.2 Experimental Paradigm 23 3.2.3 Procedure 25 3.2.4 Image acquisition 25 3.2.5 Statistical Analysis 26 3.3 Results 27 3.3.1 Behavioral Data 27 3.3.
Behavioral and neural correlates of performance feedback in younger and older adults Von der Medizinischen Fakultät der Rheinisch-Westfälischen Technischen Hochschule Aachen zur Erlangung des akademischen Grades einer Doktorin der Theoretischen Medizin genehmigte Dissertation vorgelegt von Dipl.-Psych. Lydia Beck aus Köln Berichter: Herr Universitätsprofessor Dr.phil. Dipl.-Psych. Siegfried Gauggel Herr Professor Dr.rer.nat. Dipl.-Psych. Walter Sturm Tag der mündlichen Prüfung: 8. November 2010 Diese Dissertation ist auf den Internetseiten der Hochschulbibliothek online verfügbar.
Lydia Beck – Performance feedback in younger and older adults Table of contents 1General Introduction 1 2Study One: Effects of performance feedback on executive control in younger and older adults 32.1Introduction 32.2 5Experiment 1: Feedback effect in younger adults2.2.1Introduction 52.2.2Method 62.2.3Results 92.2.4Discussion 102.3Experiment 2: Feedback effect in older adults 122.3.1Introduction 122.3.2Method 132.3.3Results 142.3.4Discussion 152.4General Discussion 17 3Study Two: Neural correlates of positive and negative performance feedback in younger and older adults 213.1Introduction 213.2Method 223.2.1Participants 223.2.2 23Experimental Paradigm3.2.3Procedure 253.2.4Image acquisition 253.2.5Statistical Analysis 263.3Results 273.3.1Behavioral Data 273.3.2Imaging Data 283.4Discussion 33
Lydia Beck – Performance feedback in younger and older adults
4General Conclusion and Future Perspective 5Summary 6Deutschsprachige Zusammenfassung 7References 8Publications and quotable abstracts 9Acknowledgments 10Erklärung § 5 Abs.1 zur Datenaufbewahrung
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Lydia Beck – Performance feedback in younger and older adults AbbreviationsANOVA BA BOLD CI EPI ES FWE fMRI FWHM FOV hrf M MNI MR MRI mm ms n N PFC RT SD TE TR
Analysis of variance Brodmann area Blood oxygenation level-dependent Confidence Interval Echo-planar imaging Effect size Family-wise error Functional magnetic resonance imaging Full-width half maximum Field of view Hemodynamic response function Mean Montreal Neurological Institute Magnetic resonance Magnetic resonance imaging Millimeters Milliseconds Number of participants per group Total number of participants Prefrontal cortex Reaction time Standard deviation Echo time Repetition time
Lydia Beck – Performance feedback in younger and older adults 1 General Introduction The termexecutive control describes a wide range of cognitive processes that are critical for the goal-directed regulation of our behavior. Examples of these cognitive processes include decision making, planning, problem-solving, setting of priorities, sequencing and inhibition of actions, monitoring, feedback processing and goal-setting. Executive control allows for an adaptive regulation of cognitive processes which enable goal-directed stimulus processing and action regulation. Previous studies have shown that executive control performance declines with age. It was demonstrated that older adults (> 60 years) revealed impaired executive control performance as compared to younger adults (Cepeda et al., 2001; Rosano et al., 2005; Treitz et al., 2007; Zelazo et al., 2004). Imaging studies have shown that during tasks for the assessment of executive control, a neural network including the prefrontal cortex (PFC) is active (Bench et al., 1993; Bunge et al., 2002; Carter et al., 1995, 1998). Especially the frontal lobes of the brain have been associated with age-related decline. This assumption is known as thefrontal hypothesis of cognitive aging(West, 1996; Raz, 2000) and has been supported by current findings (Bugaiska et al., 2007; Andrés et al., 2006). It is now well established that executive control can be divided into several subprocesses which can be impaired separately (e.g., Arbuthnott, 1995; Zelazo et al., 1997). A recent meta-analysis of neuroimaging tasks supports the distinction of separable executive control processes (Nee et al., 2007). However, it is unclear whether different executive subprocesses are differentially affected during the course of aging and if they interact with each other. Botvinick and colleagues (2001) postulate executive control as a meta-construct in which different components interact with each other in order to cope with higher order cognitive functions. The authors propose that the level of control is regulated by bottom-up as well as top-down executive processes and that these processes interact with each other. The bottom-up regulation of executive control can be assessed by the so-called flanker taskThe flanker task (Eriksen & Eriksen, 1974) is a visual. discrimination task in which the participant is required to respond to a central 1
Lydia Beck – Performance feedback in younger and older adults stimulus which is flanked by several other stimuli that can be congruent or incongruent, i.e., equal to or different from the target. As incongruent targets require more executive control exertion as compared to congruent targets, the difference between responses to both kinds of stimuli is a measure for executive control. Smaller differences indicate better executive control as compared to higher differences. The top-down regulation of action on the other hand can be assessed by the influence of feedback. It has been shown that feedback has a positive influence on performance in a variety of cognitive domains such as memory, learning, and decision-making (e.g., Ashby et al., 2002; Butler et al., 2008; Diehl & Sterman, 1995; Pashler, 2005; West et al., 2005). Still it is unclear if feedback which itself requires the exertion of executive control can improve bottom-up executive control performance. Therefore, the first study of the present thesis aimed to investigate if feedback has an influence on bottom-up executive control as measured by the flanker task and if age has a moderating influence. In a first experiment, younger adults performed the flanker task and were randomly assigned to one of two groups. The feedback group received information about their mean reaction times while the no-feedback group did not receive such information. A second experiment served to replicate the findings in a group of older adults. Effect sizes (ES) were calculated to enable a comparison between both age groups. As previous literature has demonstrated that aging is associated with the deterioration of the brain, the purpose of the second study of the present thesis was to investigate whether feedback is processed similarly in younger and older adults on a neuronal level. Event-related functional Magnetic Resonance Imaging (fMRI) was applied in the flanker task and evaluative performance feedback was provided after each trial. Differential brain activations were assessed by calculating a full factorial model with the factors age group (younger vs. older adults) and type of evaluative feedback (positive, negative, neutral). The influence of different feedback conditions on subsequent trial performance was assessed as a behavioral correlate.