Functional MRI in twins discordant for schizophrenia during a working memory task: Preliminary results from the eutwinss study

2011 ◽  
Vol 26 (S2) ◽  
pp. 938-938
Author(s):  
K. Langbein ◽  
M. Dietzek ◽  
G. Mingoia ◽  
R. Maitra ◽  
M. Weisbrod ◽  
...  

IntroductionWorking memory deficits are considered a core feature of disturbed cognition in schizophrenia. Recent neuropsychological studies in twins suggest that there are shared genetic factors between schizophrenia and executive processes.AimWe used a co-twin control design to test the hypothesis that prefrontal activation during a working memory task is seen both in affected as well as unaffected twins discordant for schizophrenia, thus reflecting genetic load on this putative endophenotype.MethodsAs part of EUTwinsS, a multi-centre collaborative study on twins with schizophrenia, we obtained functional MRI scans during a Sternberg working memory task (with one maintenance and one manipulation variations) of twins discordant for schizophrenia (5 monozygotic pairs, 7 dizygotic pairs) and compared them to 10/4 healthy MZ/DZ twins, matched for age and gender.ResultsComparing the overall task-related effects (p < 0.001, uncorrected), we found stronger activation in control twins compared to either Sz-affected or unaffected twins in the right middle frontal gyrus and medial fronto-orbital cortex, and compared to Sz-affected twins also in the left cerebellum and right inferior occipital cortex. Comparing the manipulation vs. maintenance trials, healthy controls showed stronger activation than Sz-affected twins in the left hippocampus, but smaller in right caudate and anterior cingulate, while unaffected co-twins showed diminished right middle and left superior and middle frontal gyri compared to either group.ConclusionsWhile diminished prefrontal activation in unaffected co-twins might indicate compensatory processes during executive control, the overall activation deficits are consistent with a genetic effect on prefrontal cortical efficiency.

2005 ◽  
Vol 35 (2) ◽  
pp. 187-196 ◽  
Author(s):  
A. MENDREK ◽  
K. A. KIEHL ◽  
A. M. SMITH ◽  
D. IRWIN ◽  
B. B. FORSTER ◽  
...  

Background. In a recent longitudinal study of first-episode schizophrenia patients, we found that while dysfunction of the right dorsolateral prefrontal cortex (DLPFC), right thalamus, left cerebellum and cingulate gyrus normalized with antipsychotic treatment and significant reduction in symptomatology, the left DLPFC, left thalamus, and right cerebellum remained disturbed. In the present study we investigated whether these abnormalities are also present in clinically stable, relatively well-functioning schizophrenia patients in comparison to control subjects during performance of the N-back working-memory task.Method. Twelve schizophrenia and 12 control subjects completed the study. The functional images collected during scanning were analyzed using a random-effects model in a restricted set of six regions of interest (ROIs). In addition, the exploratory search in the entire brain volume was performed.Results. The ROI analyses revealed relative underactivation in the region of the left DLPFC and the right cerebellum, as well as overactivation in the left cerebellum. The exploratory whole-brain search exposed additional overactivation in the medial frontal, anterior cingulate, and left parietal cortices.Conclusions. The present study provides evidence of significant underactivations in stable schizophrenia patients in regions that we have previously observed to be dysfunctional in acutely psychotic and partially remitted patients, together with extensive overactivations in several regions that potentially reflect some compensatory mechanism or increased effort on the working-memory task.


Author(s):  
Selma Lugtmeijer ◽  
◽  
Linda Geerligs ◽  
Frank Erik de Leeuw ◽  
Edward H. F. de Haan ◽  
...  

AbstractWorking memory and episodic memory are two different processes, although the nature of their interrelationship is debated. As these processes are predominantly studied in isolation, it is unclear whether they crucially rely on different neural substrates. To obtain more insight in this, 81 adults with sub-acute ischemic stroke and 29 elderly controls were assessed on a visual working memory task, followed by a surprise subsequent memory test for the same stimuli. Multivariate, atlas- and track-based lesion-symptom mapping (LSM) analyses were performed to identify anatomical correlates of visual memory. Behavioral results gave moderate evidence for independence between discriminability in working memory and subsequent memory, and strong evidence for a correlation in response bias on the two tasks in stroke patients. LSM analyses suggested there might be independent regions associated with working memory and episodic memory. Lesions in the right arcuate fasciculus were more strongly associated with discriminability in working memory than in subsequent memory, while lesions in the frontal operculum in the right hemisphere were more strongly associated with criterion setting in subsequent memory. These findings support the view that some processes involved in working memory and episodic memory rely on separate mechanisms, while acknowledging that there might also be shared processes.


2011 ◽  
Vol 42 (1) ◽  
pp. 29-40 ◽  
Author(s):  
R. Kerestes ◽  
C. D. Ladouceur ◽  
S. Meda ◽  
P. J. Nathan ◽  
H. P. Blumberg ◽  
...  

BackgroundPatients with major depressive disorder (MDD) show deficits in processing of facial emotions that persist beyond recovery and cessation of treatment. Abnormalities in neural areas supporting attentional control and emotion processing in remitted depressed (rMDD) patients suggests that there may be enduring, trait-like abnormalities in key neural circuits at the interface of cognition and emotion, but this issue has not been studied systematically.MethodNineteen euthymic, medication-free rMDD patients (mean age 33.6 years; mean duration of illness 34 months) and 20 age- and gender-matched healthy controls (HC; mean age 35.8 years) performed the Emotional Face N-Back (EFNBACK) task, a working memory task with emotional distracter stimuli. We used blood oxygen level-dependent (BOLD) functional magnetic resonance imaging (fMRI) to measure neural activity in the dorsolateral (DLPFC) and ventrolateral prefrontal cortex (VLPFC), orbitofrontal cortex (OFC), ventral striatum and amygdala, using a region of interest (ROI) approach in SPM2.ResultsrMDD patients exhibited significantly greater activity relative to HC in the left DLPFC [Brodmann area (BA) 9/46] in response to negative emotional distracters during high working memory load. By contrast, rMDD patients exhibited significantly lower activity in the right DLPFC and left VLPFC compared to HC in response to positive emotional distracters during high working memory load. These effects occurred during accurate task performance.ConclusionsRemitted depressed patients may continue to exhibit attentional biases toward negative emotional information, reflected by greater recruitment of prefrontal regions implicated in attentional control in the context of negative emotional information.


2015 ◽  
Vol 27 (8) ◽  
pp. 1633-1647 ◽  
Author(s):  
Ben Deen ◽  
Rebecca Saxe ◽  
Marina Bedny

In congenital blindness, the occipital cortex responds to a range of nonvisual inputs, including tactile, auditory, and linguistic stimuli. Are these changes in functional responses to stimuli accompanied by altered interactions with nonvisual functional networks? To answer this question, we introduce a data-driven method that searches across cortex for functional connectivity differences across groups. Replicating prior work, we find increased fronto-occipital functional connectivity in congenitally blind relative to blindfolded sighted participants. We demonstrate that this heightened connectivity extends over most of occipital cortex but is specific to a subset of regions in the inferior, dorsal, and medial frontal lobe. To assess the functional profile of these frontal areas, we used an n-back working memory task and a sentence comprehension task. We find that, among prefrontal areas with overconnectivity to occipital cortex, one left inferior frontal region responds to language over music. By contrast, the majority of these regions responded to working memory load but not language. These results suggest that in blindness occipital cortex interacts more with working memory systems and raise new questions about the function and mechanism of occipital plasticity.


1994 ◽  
Vol 1 (4) ◽  
pp. 293-304 ◽  
Author(s):  
Jonathan D. Cohen ◽  
Steven D. Forman ◽  
Todd S. Braver ◽  
B. J. Casey ◽  
David Servan-Schreiber ◽  
...  

2013 ◽  
Vol 25 (4pt1) ◽  
pp. 931-941 ◽  
Author(s):  
Jacqueline Bruce ◽  
Philip A. Fisher ◽  
Alice M. Graham ◽  
William E. Moore ◽  
Shannon J. Peake ◽  
...  

AbstractChildren in foster care have often encountered a range of adverse experiences, including neglectful and/or abusive care and multiple caregiver transitions. Prior research findings suggest that such experiences negatively affect inhibitory control and the underlying neural circuitry. In the current study, event-related functional magnetic resonance imaging was employed during a go/no go task that assesses inhibitory control to compare the behavioral performance and brain activation of foster children and nonmaltreated children. The sample included two groups of 9- to 12-year-old children: 11 maltreated foster children and 11 nonmaltreated children living with their biological parents. There were no significant group differences on behavioral performance on the task. In contrast, patterns of brain activation differed by group. The nonmaltreated children demonstrated stronger activation than did the foster children across several regions, including the right anterior cingulate cortex, the middle frontal gyrus, and the right lingual gyrus, during correct no go trials, whereas the foster children displayed stronger activation than the nonmaltreated children in the left inferior parietal lobule and the right superior occipital cortex, including the lingual gyrus and cuneus, during incorrect no go trials. These results provide preliminary evidence that the early adversity experienced by foster children impacts the neural substrates of inhibitory control.


2011 ◽  
Vol 64 (11) ◽  
pp. 2168-2180 ◽  
Author(s):  
Joanna L. Brooks ◽  
Robert H. Logie ◽  
Robert McIntosh ◽  
Sergio Della Sala

Two experiments explored lateralized biases in mental representations of matrix patterns formed from aural verbal descriptions. Healthy participants listened, either monaurally or binaurally, to verbal descriptions of 6 by 3 matrix patterns and were asked to form a mental representation of each pattern. In Experiment 1, participants were asked to judge which half of the matrix, left or right, contained more filled cells and to rate the certainty of their judgement. Participants tended to judge that the left side was fuller than the right and showed significantly greater certainty when judging patterns that were fuller on the left. This tendency was particularly strong for left-ear presentation. In Experiment 2, participants conducted the same task as that in Experiment 1 but were also asked to recall the pattern for the side judged as fuller. Participants were again more certain in judging patterns that were fuller on the left—particularly for left-ear presentation—but were no more accurate in remembering the details from the left. These results suggest that the left side of the mental representation was represented more saliently but it was not remembered more accurately. We refer to this lateralized bias as “representational pseudoneglect”. Results are discussed in terms of theories of visuospatial working memory.


2011 ◽  
Vol 17 (6) ◽  
pp. 1080-1093 ◽  
Author(s):  
C.B. Hartberg ◽  
K. Sundet ◽  
L.M. Rimol ◽  
U.K. Haukvik ◽  
E.H. Lange ◽  
...  

AbstractRelationships between cortical brain structure and neurocognitive functioning have been reported in schizophrenia, but findings are inconclusive, and only a few studies in bipolar disorder have addressed this issue. This is the first study to directly compare relationships between cortical thickness and surface area with neurocognitive functioning in patients with schizophrenia (n = 117) and bipolar disorder (n = 121) and healthy controls (n = 192). MRI scans were obtained, and regional cortical thickness and surface area measurements were analyzed for relationships with test scores from 6 neurocognitive domains. In the combined sample, cortical thickness in the right rostral anterior cingulate was inversely related to working memory, and cortical surface area in four frontal and temporal regions were positively related to neurocognitive functioning. A positive relationship between left transverse temporal thickness and processing speed was specific to schizophrenia. A negative relationship between right temporal pole thickness and working memory was specific to bipolar disorder. In conclusion, significant cortical structure/function relationships were found in a large sample of healthy controls and patients with schizophrenia or bipolar disorder. The differences that were found between schizophrenia and bipolar may indicate differential relationship patterns in the two disorders, which may be of relevance for understanding the underlying pathophysiology. (JINS, 2011, 17, 1080–1093)


2009 ◽  
Vol 194 (1) ◽  
pp. 25-33 ◽  
Author(s):  
Matthew R. Broome ◽  
Pall Matthiasson ◽  
Paolo Fusar-Poli ◽  
James B. Woolley ◽  
Louise C. Johns ◽  
...  

BackgroundPeople with prodromal symptoms have a very high risk of developing psychosis.AimsTo use functional magnetic resonance imaging to examine the neurocognitive basis of this vulnerability.MethodCross-sectional comparison of regional activation in individuals with an ‘at-risk mental state’ (at-risk group: n=17), patients with first-episode schizophreniform psychosis (psychosis group: n=10) and healthy volunteers (controls: n=15) during an overt verbal fluency task and an N-back working memory task.ResultsA similar pattern of between-group differences in activation was evident across both tasks. Activation in the at-risk group was intermediate relative to that in controls and the psychosis group in the inferior frontal and anterior cingulate cortex during the verbal fluency task and in the inferior frontal, dorsolateral prefrontal and parietal cortex during the N-back task.ConclusionsThe at-risk mental state is associated with abnormalities of regional brain function that are qualitatively similar to, but less severe than, those in patients who have recently presented with psychosis.


2018 ◽  
Author(s):  
Robert M Mok ◽  
M. Clare O'Donoghue ◽  
Nicholas E Myers ◽  
Erin H.S. Drazich ◽  
Anna Christina Nobre

Working memory (WM) is essential for normal cognitive function, but shows marked decline in aging. Studies have shown that the ability to attend selectively to relevant information amongst competing distractors is related to WM capacity. The extent to which WM deficits in aging are related to impairments in selective attention is unclear. To investigate the neural mechanisms supporting selective attention in WM in aging, we tested a large group of older adults using functional magnetic resonance imaging whilst they performed a category-based (faces/houses) selective-WM task. Older adults were able to use attention to encode targets and suppress distractors to reach high levels of task performance. A subsequent, surprise recognition-memory task showed strong consequences of selective attention. Attended items in the relevant category were recognised significantly better than items in the ignored category. Neural measures also showed reliable markers of selective attention during WM. Purported control regions including the dorsolateral and inferior prefrontal and anterior cingulate cortex were reliably recruited for attention to both categories. Activation levels in category-sensitive visual cortex showed reliable modulation according to attentional demands, and positively correlated with subsequent memory measures of attention and WM span. Psychophysiological interaction analyses showed that activity in category-sensitive areas were coupled with non-sensory cortex known to be involved in cognitive control and memory processing, including regions in the PFC and hippocampus. In summary, we found that brain mechanisms of attention for selective WM are relatively preserved in aging, and individual differences in these abilities corresponded to the degree of attention-related modulation in the brain.


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