Mark Dekker. Aging and Cognitive Control. Proefschrift Rijksuniversiteit Groningen, 2009.

bespreking Mark Dekker. Aging and Cognitive Control. Proefschrift Rijksuniversiteit Groningen, 2009. Executieve functies, oftewel cognitieve controle processen, hebben betrekking op die functies die van belang zijn bij het aansturen van gedrag en handelingen. Over het algemeen wordt het executief functioneren gebruikt als een overkoepelende term waaronder meerdere processen geschaard worden. Zo worden flexibiliteit, planning, het werkgeheugen, generatie en inhibitie, maar ook sociale opvattingen en gedrag, allemaal onder het executief functioneren genoemd. Dit roept direct de vraag op of we als we het over executieve functies hebben, kunnen spreken over een enkele functie of dat het onderscheid tussen de verschillende functies wel degelijk van belang is. Aangezien deze functies zeer gevoelig zijn voor het effect van leeftijd, is een essentiële vraag of gezonde veroudering gepaard gaat met een algehele afname van het executief functioneren, of dat juist het onderscheid tussen de functies relevant is

The Influence of Executive Functioning on Facial and Subjective Pain Responses in Older Adults

Cognitive decline is known to reduce reliability of subjective pain reports. Although facial expressions of pain are generally considered to be less affected by this decline, empirical support for this assumption is sparse. The present study therefore examined how cognitive functioning relates to facial expressions of pain and whether cognition acts as a moderator between nociceptive intensity and facial reactivity. Facial and subjective responses of 51 elderly participants to mechanical stimulation at three intensities levels (50 kPa, 200 kPa, and 400 kPa) were assessed. Moreover, participants completed a neuropsychological examination of executive functioning (planning, cognitive inhibition, and working memory), episodic memory, and psychomotor speed. The results showed that executive functioning has a unique relationship with facial reactivity at low pain intensity levels (200 kPa). Moreover, cognitive inhibition (but not other executive functions) moderated the effect of pressure intensity on facial pain expressions, suggesting that the relationship between pressure intensity and facial reactivity was less pronounced in participants with high levels of cognitive inhibition. A similar interaction effect was found for cognitive inhibition and subjective pain report. Consequently, caution is needed when interpreting facial (as well as subjective) pain responses in individuals with a high level of cognitive inhibition

The presence of attentional and interpretation biases in patients with severe MS-related fatigue

Objective: Severe fatigue is a prevalent and disabling symptom in Multiple Sclerosis (MS). This study tested if a fatigue and physical activity-related attentional bias (AB), and a somatic interpretation bias (IB) is present in severely fatigued patients with MS, compared to healthy controls and patients with chronic fatigue syndrome (CFS/ME). Method: Severely fatigued patients with MS or CFS/ME and healthy controls completed a Visual Probe Task (VPT) assessing fatigue and physical activity-related AB, and an IB task that assesses the tendency to interpret ambiguous information in either a somatically threatening way or in a more neutral manner. The VPT was completed by 38 MS patients, 44 CFS/ME patients, and 46 healthy controls, the IB task by respectively 156, 40 and 46 participants. Results: ANOVA showed no statistical significant group differences in a fatigue-related AB or physical activity-related AB (omnibus test of interaction between topic*condition: F2,125 = 1.87; p = .159). Both patient groups showed a tendency to interpret ambiguous information in a somatically threatening way compared to healthy controls (F1,2 = 27.61, p &lt; .001). This IB was significantly stronger in MS patients compared to ME/CFS patients. IB was significantly correlated with cognitive responses to symptoms in MS patients. Conclusion: MS patients tend to interpret ambiguous information in a somatically threatening way. This may feed into unhelpful ways of dealing with symptoms, possibly contributing to perpetuation of severe fatigue in MS. Keywords: attentional bias, interpretation bias, fatigue, multiple sclerosis<br/

Rule induction performance in amnestic mild cognitive impairment and Alzheimer’s dementia: examining the role of simple and biconditional rule learning processes

Introduction: Rule induction tests such as the Wisconsin Card Sorting Test require executive control processes, but also the learning and memorization of simple stimulus–response rules. In this study, we examined the contribution of diminished learning and memorization of simple rules to complex rule induction test performance in patients with amnestic mild cognitive impairment (aMCI) or Alzheimer’s dementia (AD). Method: Twenty-six aMCI patients, 39 AD patients, and 32 control participants were included. A task was used in which the memory load and the complexity of the rules were independently manipulated. This task consisted of three conditions: a simple two-rule learning condition (Condition 1), a simple four-rule learning condition (inducing an increase in memory load, Condition 2), and a complex biconditional four-rule learning condition—inducing an increase in complexity and, hence, executive control load (Condition 3). Results: Performance of AD patients declined disproportionately when the number of simple rules that had to be memorized increased (from Condition 1 to 2). An additional increment in complexity (from Condition 2 to 3) did not, however, disproportionately affect performance of the patients. Performance of the aMCI patients did not differ from that of the control participants. In the patient group, correlation analysis showed that memory performance correlated with Condition 1 performance, whereas executive task performance correlated with Condition 2 performance. Conclusions: These results indicate that the reduced learning and memorization of underlying task rules explains a significant part of the diminished complex rule induction performance commonly reported in AD, although results from the correlation analysis suggest involvement of executive control functions as well. Taken together, these findings suggest that care is needed when interpreting rule induction task performance in terms of executive function deficits in these patients

White matter hyperintensities and working memory: an explorative study

Contains fulltext : 73317.pdf (publisher's version ) (Closed access)White matter hyperintensities (WMH) are commonly observed in elderly people and may have the most profound effect on executive functions, including working memory. Surprisingly, the Digit Span backward, a frequently employed working memory task, reveals no association with WMH. In the present study, it was investigated whether more detailed analyses of WMH variables and study sample selection are important when establishing a possible relationship between the Digit Span backward and WMH. To accomplish this, the Digit Span backward and additional working memory tests, WMH subscores, and cardiovascular risk factors were examined. The results revealed that performance on the Digit Span backward test is unrelated to WMH, whereas a relationship between other working memory tests and WMH was confirmed. Furthermore, a division between several white matter regions seems important; hyperintensities in the frontal deep white matter regions were the strongest predictor of working memory performance.16 p

Relationship between chronic pain and cognition in cognitively intact older persons and patients with Alzheimer's disease; the need to control for mood

Background: Brain areas that are involved in cognition and mood also play a role in pain processing. Objective: The goal of the present study was to examine the relationship between chronic pain and cognition [executive functions (EF) and memory], while controlling for mood, in cognitively intact older persons and in patients with Alzheimer's disease (AD). Methods: Two groups of subjects participated: 20 older persons without dementia and 19 patients in an early stage of probable AD who suffered from arthrosis/arthritis. Pain intensity and pain affect were assessed by the Colored Analogue Scale for Pain Intensity and for Pain Affect, the Faces Pain Scale (FPS) and the Number of Words Chosen-Affective (NWC-A). Level of depression and anxiety were evaluated by questionnaires. EF and memory were assessed by neuropsychological tests. Results: The results show that significant correlations between specific cognitive functions, pain intensity and pain affect were lacking in the cognitively intact older persons. Cognition, in particular memory, appeared to be related to depressive symptoms. In contrast, a significant positive correlation was observed between EF, pain intensity and pain affect measured by the FPS in the AD group. Conclusions: Although older persons with depression were excluded, in studies on pain and cognition one should control for the presence of depressive symptoms in older persons with and without dementia. Copyright © 2008 S. Karger AG

The Influence of Executive Functioning on Facial and Subjective Pain Responses in Older Adults

Cognitive decline is known to reduce reliability of subjective pain reports. Although facial expressions of pain are generally considered to be less affected by this decline, empirical support for this assumption is sparse.The present study therefore examined how cognitive functioning relates to facial expressions of pain and whether cognition acts as a moderator between nociceptive intensity and facial reactivity. Facial and subjective responses of 51 elderly participants tomechanical stimulation at three intensities levels (50 kPa, 200 kPa, and 400 kPa) were assessed. Moreover, participants completed a neuropsychological examination of executive functioning (planning, cognitive inhibition, and working memory), episodic memory, and psychomotor speed. The results showed that executive functioning has a unique relationship with facial reactivity at low pain intensity levels (200 kPa). Moreover, cognitive inhibition (but not other executive functions) moderated the effect of pressure intensity on facial pain expressions, suggesting that the relationship between pressure intensity and facial reactivity was less pronounced in participants with high levels of cognitive inhibition. A similar interaction effect was found for cognitive inhibition and subjective pain report. Consequently, caution is needed when interpreting facial (as well as subjective) pain responses in individuals with a high level of cognitive inhibition.status: publishe

Pain and executive functions: a unique relationship between Stroop task and experimentally induced pain

There is a growing body of evidence that a higher level of cognitive inhibition is associated with lower experimental pain sensitivity. However, a systematic examination of the association between executive functions, which include not only inhibition but also updating and shifting, and experimental pain sensitivity is lacking. This study aimed to overcome this limitation by exploring the relationship between a range of executive functions and different measures of experimentally induced cold pain in healthy participants. In a group of 54 healthy participants (age 21-24 years), executive functions (EF) were investigated in a systematic manner following a well-established framework developed by Miyake and collaborators. The investigation included multiple tests of inhibition (Stroop, Stop-signal, and Left-right), updating (Keep-track, Letter-memory, and Spatial n-back), and set-shifting (Plus-minus, Number-letter, and Local-global). The cold pressor test was used to obtain measures of pain threshold (the first sensation of pain), sensitivity to pain (the moment when substantial pain was reported), and pain tolerance (the moment when pain became unbearable). Results showed no relationship between pain measures and measures of updating and shifting. All pain measures were related to Stroop interference inhibition score, but not to other two inhibition tasks. Further analyses confirmed the unique relationship between Stroop-type of inhibition and response to pain. We argue that there is a fundamental relationship between cognitive inhibition and pain experience, which relies on one's ability to suppress automatic processes