Lisbeth Evers - Academia.edu (original) (raw)
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Papers by Lisbeth Evers
Brain and Cognition, 2009
The objective of this study was to examine response inhibition-and feedback-related neural activi... more The objective of this study was to examine response inhibition-and feedback-related neural activity in adults with attention deficit hyperactivity disorder (ADHD) using event-related functional MRI. Sixteen male adults with ADHD and 13 healthy/normal controls participated in this study and performed a modified Go/NoGo task. Behaviourally, attention and inhibition problems in the ADHD group were observed; no feedback-related differences between the groups were detected. The neuroimaging data showed that the ADHD group displayed more activation in the inferior frontal gyrus and putamen during response inhibition. During feedback-related processes, the ADHD group displayed less activation in the inferior frontal/orbitofrontal cortex, hippocampus/nucleus accumbens, and caudate nucleus, but more activity in the inferior frontal gyrus. These results indicate that at least two distinguishable underlying brain networks related to response inhibition and feedback are altered in adults with ADHD.
Healthy cognitive aging is thought to impact most heavily on episodic memory [1]. However, change... more Healthy cognitive aging is thought to impact most heavily on episodic memory [1]. However, changes in episodic memory prior to the age of 60 are more controversial than changes in older adults [2]. Furthermore, cognitive decline already present in middle age may not yet manifest in behavior due to the action of neural compensation processes that preserve performance at the
Alzheimer's & Dementia, 2011
Background: Cerebral aging is associated with changes in brain structure as well as with changes ... more Background: Cerebral aging is associated with changes in brain structure as well as with changes in neural activity. The links between structural and functional changes are still largely unknown. The present study explored the relationship between volume and memory-related brain activation within several gray matter regions. Methods: MRI and fMRI scans were acquired of 37 healthy older individuals (mean age 67 years, SD 9.9). Gray matter volumes and the haemodynamic response on a verbal memory task were measured in three brain areas, viz.: the hippocampus, the parahippocampal gyrus, and the inferior prefrontal cortex. Results: We found a significant association between gray matter volume and activation in the left and right hippocampus as well as in the right inferior prefrontal cortex. These associations were all positive, indicating that smaller volumes were associated with less activation. However, we found no link with the factor age, which was in line with most previous studies performed to date. This indicates that associations between gray matter volume and activation within brain areas are not necessarily related to brain aging. Conclusions: We argue that structure-function relationships in aging individuals do not necessarily reflect age-related deterioration and that they might just as well reflect the normal architecture of the healthy brain.
Current Pharmaceutical Design, 2010
Acute tryptophan depletion (ATD), a method to temporarily lower central serotonin levels, has bee... more Acute tryptophan depletion (ATD), a method to temporarily lower central serotonin levels, has been used to study the functioning of the serotonergic system. Relatively recent studies that examined the effects of ATD on brain activation associated with cognitive and emotional processing in healthy volunteers are reviewed. An overview of the findings in healthy volunteers is important for the interpretation of the effect of ATD on brain activation in patients with an affective disorder, such as major depression. These studies show that during response control and negative feedback processing ATD modulates the BOLD response in the inferior/orbitofrontal cortex, the anterior cingulate cortex and the dorsomedial prefrontal cortex. During emotional processing, it is consistently found that ATD modulates the BOLD response in the amygdala. These brain regions also show abnormal activation in depressed patients.
Brain and Cognition, 2009
The objective of this study was to examine response inhibition-and feedback-related neural activi... more The objective of this study was to examine response inhibition-and feedback-related neural activity in adults with attention deficit hyperactivity disorder (ADHD) using event-related functional MRI. Sixteen male adults with ADHD and 13 healthy/normal controls participated in this study and performed a modified Go/NoGo task. Behaviourally, attention and inhibition problems in the ADHD group were observed; no feedback-related differences between the groups were detected. The neuroimaging data showed that the ADHD group displayed more activation in the inferior frontal gyrus and putamen during response inhibition. During feedback-related processes, the ADHD group displayed less activation in the inferior frontal/orbitofrontal cortex, hippocampus/nucleus accumbens, and caudate nucleus, but more activity in the inferior frontal gyrus. These results indicate that at least two distinguishable underlying brain networks related to response inhibition and feedback are altered in adults with ADHD.
Healthy cognitive aging is thought to impact most heavily on episodic memory [1]. However, change... more Healthy cognitive aging is thought to impact most heavily on episodic memory [1]. However, changes in episodic memory prior to the age of 60 are more controversial than changes in older adults [2]. Furthermore, cognitive decline already present in middle age may not yet manifest in behavior due to the action of neural compensation processes that preserve performance at the
Alzheimer's & Dementia, 2011
Background: Cerebral aging is associated with changes in brain structure as well as with changes ... more Background: Cerebral aging is associated with changes in brain structure as well as with changes in neural activity. The links between structural and functional changes are still largely unknown. The present study explored the relationship between volume and memory-related brain activation within several gray matter regions. Methods: MRI and fMRI scans were acquired of 37 healthy older individuals (mean age 67 years, SD 9.9). Gray matter volumes and the haemodynamic response on a verbal memory task were measured in three brain areas, viz.: the hippocampus, the parahippocampal gyrus, and the inferior prefrontal cortex. Results: We found a significant association between gray matter volume and activation in the left and right hippocampus as well as in the right inferior prefrontal cortex. These associations were all positive, indicating that smaller volumes were associated with less activation. However, we found no link with the factor age, which was in line with most previous studies performed to date. This indicates that associations between gray matter volume and activation within brain areas are not necessarily related to brain aging. Conclusions: We argue that structure-function relationships in aging individuals do not necessarily reflect age-related deterioration and that they might just as well reflect the normal architecture of the healthy brain.
Current Pharmaceutical Design, 2010
Acute tryptophan depletion (ATD), a method to temporarily lower central serotonin levels, has bee... more Acute tryptophan depletion (ATD), a method to temporarily lower central serotonin levels, has been used to study the functioning of the serotonergic system. Relatively recent studies that examined the effects of ATD on brain activation associated with cognitive and emotional processing in healthy volunteers are reviewed. An overview of the findings in healthy volunteers is important for the interpretation of the effect of ATD on brain activation in patients with an affective disorder, such as major depression. These studies show that during response control and negative feedback processing ATD modulates the BOLD response in the inferior/orbitofrontal cortex, the anterior cingulate cortex and the dorsomedial prefrontal cortex. During emotional processing, it is consistently found that ATD modulates the BOLD response in the amygdala. These brain regions also show abnormal activation in depressed patients.