scholarly journals A critical role for human ventromedial frontal lobe in value comparison based on multi-attribute configuration

2018 ◽  
Author(s):  
Gabriel Pelletier ◽  
Lesley K. Fellows

ABSTRACTReal-life decisions are often between options with multiple value-relevant attributes. Neuroeconomic models propose that the value associated with each attribute is integrated in a global value for each option. However, evidence from patients with ventromedial frontal (VMF) damage argues against a very general role for this region in value integration, suggesting instead that it contributes critically to specific value inference or comparison processes. Here, we tested value-based decision-making between artificial multi-attribute objects in 12 men and women with focal damage to VMF, compared to a healthy control group (N=24) and a control group with frontal lobe damage sparing VMF (N=12). In a ‘configural’ condition, overall object value was predicted by the conjunction of two attributes, while in an ‘elemental’ condition, object value could be assessed by combining the independent values of individual attributes. Patients with VMF damage were impaired in making choices when value was uniquely predicted by the configuration of attributes, but intact when choosing based on elemental attribute-values. This is evidence that VMF is critical for inferring the value of whole objects in multi-attribute choice. These findings have implications for models of value-based choice, and add to emerging views of how this region may interact with medial temporal lobe systems involved in configural object processing and relational memory.

2020 ◽  
Vol 30 (6) ◽  
pp. 3632-3643
Author(s):  
Gabriel Pelletier ◽  
Lesley K Fellows

Abstract Whether you are a gazelle bounding to the richest tract of grassland or a return customer heading to the freshest farm stand at a crowded market, the ability to learn the value of spatial locations is important in adaptive behavior. The ventromedial frontal lobe (VMF) is implicated in value-based decisions between objects and in flexibly learning to choose between objects based on feedback. However, it is unclear if this region plays a material-general role in reward learning. Here, we tested whether VMF is necessary for learning the value of spatial locations. People with VMF damage were compared with healthy participants and a control group with frontal damage sparing VMF in an incentivized spatial search task. Participants chose among spatial targets distributed among distractors, rewarded with an expected value that varied along the right-left axis of the screen. People with VMF damage showed a weaker tendency to reap reward in contralesional hemispace. In some individuals, this impairment could be dissociated from the ability to make value-based decisions between objects, assessed separately. This is the first evidence that the VMF is critically involved in reward-guided spatial search and offers a novel perspective on the relationships between value, spatial attention, and decision-making.


2020 ◽  
Vol 30 (6) ◽  
pp. 3827-3837 ◽  
Author(s):  
Alex Kafkas ◽  
Andrew R Mayes ◽  
Daniela Montaldi

Abstract The neural basis of memory is highly distributed, but the thalamus is known to play a particularly critical role. However, exactly how the different thalamic nuclei contribute to different kinds of memory is unclear. Moreover, whether thalamic connectivity with the medial temporal lobe (MTL), arguably the most fundamental memory structure, is critical for memory remains unknown. We explore these questions using an fMRI recognition memory paradigm that taps familiarity and recollection (i.e., the two types of memory that support recognition) for objects, faces, and scenes. We show that the mediodorsal thalamus (MDt) plays a material-general role in familiarity, while the anterior thalamus plays a material-general role in recollection. Material-specific regions were found for scene familiarity (ventral posteromedial and pulvinar thalamic nuclei) and face familiarity (left ventrolateral thalamus). Critically, increased functional connectivity between the MDt and the parahippocampal (PHC) and perirhinal cortices (PRC) of the MTL underpinned increases in reported familiarity confidence. These findings suggest that familiarity signals are generated through the dynamic interaction of functionally connected MTL-thalamic structures.


2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Jiliang Fang ◽  
Danhong Wang ◽  
Qing Zhao ◽  
Yang Hong ◽  
Yulian Jin ◽  
...  

Objective. To explore acupuncture effects on brain functional connectivity in patients with functional dyspepsia (FD).Methods. Eight patients in an acupuncture treatment group and ten healthy adults in the control group participated in the study. Acupuncture effectiveness was evaluated based on changes of the gastrointestinal symptoms, gastric motility measurements, and gastrin levels and comparisons with the control group when appropriate. To investigate functional connectivity changes related to FD and potential modulation after acupuncture, a set of regions of interest (ROIs) were selected according to previous fMRI reports of acupuncture.Results. Patients showed significant improvements of FD signs and symptoms after acupuncture treatments. For all of the ROIs, we identified subportions of the networks showing reduced connectivity in patients with FD. Connectivity between the ROIs and corresponding disease targets showed significant improvement after acupuncture treatment (P<0.05) in all ROIs except for right medial temporal lobe-hippocampus and right inferior parietal lobule.Conclusion. Functional connectivity of the brain is changed in patients with FD but approximates that in healthy control after acupuncture treatment. The relief of gastrointestinal signs and symptoms by acupuncture is likely due to the normalization of brain-gut axis associated with FD.


2004 ◽  
Vol 16 (1) ◽  
pp. 15-23 ◽  
Author(s):  
M. M. Kishiyama ◽  
A. P. Yonelinas ◽  
M. M. Lazzara

The ability to detect novelty is a characteristic of all mammalian nervous systems (Sokolov, 1963), and it plays a critical role in memory in the sense that items that are novel, or distinctive, are remembered better than those that are less distinct (von Restorff, 1933). Although several brain areas are sensitive to stimulus novelty, it is not yet known which regions play a role in producing novelty-related effects on memory. In the current study, we investigated novelty effects on recognition memory in amnesic patients and healthy control subjects. The control subjects demonstrated better recognition for items that were novel (i.e., presented in an infrequent color), and this effect was found for both recollection and familiarity-based responses. However, the novelty advantage was effectively eliminated in patients with extensive medial temporal lobe damage, mild hypoxic patients expected to have relatively selective hippocampal damage, and in a patient with thalamic lesions. The results indicate that the human medial temporal lobes play a critical role in producing normal novelty effects in memory.


2003 ◽  
Vol 9 (1) ◽  
pp. 31-44 ◽  
Author(s):  
NICK ALDERMAN ◽  
PAUL W. BURGESS ◽  
CAROLINE KNIGHT ◽  
COLLETTE HENMAN

Shallice and Burgess (1991) reported the utility of the Multiple Errands Test (MET) in discriminating executive deficits in three frontal lobe patients with preserved high IQ, who were otherwise unimpaired on tests of executive function. The aim of this study was to ascertain the value of a simplified version of the MET (MET–SV) for use with the range of people more routinely encountered in clinical practice. Main findings were as follows: 1) The test discriminated well between neurological patients and controls, and the group effects remained when the difference in current general cognitive functions (WAIS–R FSIQ) was taken into account. 2) The best predictors of performance in the healthy control group (n = 46) were age and the number of times participants asked for help (with more requests associated with poorer performance). 3) In the neurological group, two clear patterns of failure emerged, with performance either characterized by rule breaking or failure to achieve tasks. These two patterns were associated with different dysexecutive symptoms in everyday life. 4) The patients not only made more errors than controls, but also different ones. A scoring method that took this into account markedly increased test sensitivity. 5) Many patients passed traditional tests of executive frontal lobe function but still failed the MET–SV. This pattern was strongly associated with observed dysexecutive symptoms in everyday life. The results demonstrate the clinical utility of the test, and suggest that there are two common and independent sources of failure on multitasking tests in a general neurological population: memory dysfunction, and initiation problems. (JINS, 2003, 9, 31–44.)


2019 ◽  
Author(s):  
Alex Kafkas ◽  
Andrew R. Mayes ◽  
Daniela Montaldi

AbstractThe neural basis of memory is highly distributed, but the thalamus is known to play a particularly critical role. However, exactly how the different thalamic nuclei contribute to different kinds of memory is unclear. Moreover, whether thalamic connectivity with the medial temporal lobe (MTL), arguably the most fundamental memory structure, is critical for memory, remains unknown. We explore these questions using an fMRI recognition memory paradigm that taps familiarity and recollection (i.e., the two types of memory that support recognition) for objects, faces and scenes. We show that the mediodorsal thalamus (MDt) plays a material-general role in familiarity, while the anterior thalamus plays a material-general role in recollection. Material-specific regions were found for scene familiarity (ventral posteromedial and pulvinar thalamic nuclei) and face familiarity (left ventrolateral thalamus). Critically, increased functional connectivity between the MDt and the parahippocampal (PHC) and perirhinal cortices (PRC) of the MTL underpinned increases in reported familiarity confidence. These findings suggest that familiarity signals are generated through the dynamic interaction of functionally connected MTL-thalamic structures.


2016 ◽  
Vol 86 (1-2) ◽  
pp. 9-17 ◽  
Author(s):  
Bekir Ucan ◽  
Mustafa Sahin ◽  
Muyesser Sayki Arslan ◽  
Nujen Colak Bozkurt ◽  
Muhammed Kizilgul ◽  
...  

Abstract.The relationship between Hashimoto’s thyroiditis and vitamin D has been demonstrated in several studies. The aim of the present study was to evaluate vitamin D concentrations in patients with Hashimoto’s thyroiditis, the effect of vitamin D therapy on the course of disease, and to determine changes in thyroid autoantibody status and cardiovascular risk after vitamin D therapy. We included 75 patients with Hashimoto’s thyroiditis and 43 healthy individuals. Vitamin D deficiency is defined as a 25-hydroxy vitamin D (25(OH)D3) concentration less than 20ng/mL. Vitamin D deficient patients were given 50.000 units of 25(OH)D3 weekly for eight weeks in accordance with the Endocrine Society guidelines. All evaluations were repeated after 2 months of treatment. Patients with Hashimoto’s thyroiditis had significantly lower vitamin D concentrations compared with the controls (9.37±0.69 ng/mL vs 11.95±1.01 ng/mL, p < 0.05, respectively). Thyroid autoantibodies were significantly decreased by vitamin D replacement treatment in patients with euthyroid Hashimoto’s thyroiditis. Also, HDL cholesterol concentrations improved in the euthyroid Hashimoto group after treatment. The mean free thyroxine (fT4) concentrations were 0.89±0.02 ng/dL in patients with Hashimoto’s thyroiditis and 1.07±0.03 ng/dL in the healthy control group (p < 0.001). The mean thyroid volumes were 7.71±0.44 mL in patients with Hashimoto’s thyroiditis and 5.46±0.63 mL in the healthy control group (p < 0.01). Vitamin D deficiency is frequent in Hashimoto’s thyroiditis and treatment of patients with this condition with Vitamin D may slow down the course of development of hypothyroidism and also decrease cardiovascular risks in these patients. Vitamin D measurement and replacement may be critical in these patients.


1997 ◽  
Vol 78 (03) ◽  
pp. 0990-0992 ◽  
Author(s):  
Andreas Hillarp ◽  
Bengt Zӧller ◽  
Peter J Svensson ◽  
Bjӧrn Dahlbäck

SummaryA dimorphism in the 3’-untranslated region of the prothrombin gene (G to A transition at position 20210) has recently been reported to be associated with increases in plasma prothrombin levels and in the risk of venous thrombosis (1). We have examined the prothrombin dimorphism among 99 unselected outpatients with phlebography verified deep venous thrombosis, and in 282 healthy controls. The prevalence of the 20210 A allele was 7.1% (7/99) in the patient group, and 1.8% (5/282) in the healthy control group (p = 0.0095). The relative risk of venous thrombosis was calculated to be 4.2 (95% Cl, 1.3 to 13.6), and was still significant when adjustment was made for age, sex and the factor V:R506Q mutation causing APC resistance [odds ratio 3.8 (95% Cl, 1.1 13.2)]. As previously reported, 28% of the patients were carriers of the factor V:R506Q mutation. Thus, 34% (one patient carried both traits) of unselected patients with deep venous thrombosis were carriers of an inherited prothrombotic disorder. To sum up, our results confirm the 20210 A allele of the prothrombin gene to be an important risk factor for venous thrombosis.


2020 ◽  
Vol 26 (27) ◽  
pp. 3341-3348 ◽  
Author(s):  
Marek Femlak ◽  
Anna Gluba-Brzozka ◽  
Beata Franczyk ◽  
Jacek Rysz

Introduction: Diabetes mellitus (DM) due to its increasing prevalence and associated morbidity and mortality has become a serious public health problem. In DM, HDL may lose its beneficial features and become proatherogenic due to its altered biological activity thus increasing cardiovascular risk. The aim of this study was to assess the influence of the presence of diabetes mellitus type 2 and its duration on the distribution of HDL subfractions. Moreover, the effect of statin treatment on HDL subfraction share was analysed in this study. Methods: The study group consisted of 50 patients with newly diagnosed DM and 50 persons with DM for longer than 10 years while the control group consisted of 50 healthy volunteers. HDL subfractions were analysed with the use of Lipoprint. Results: We demonstrated progressive worsening of heart functioning and impairment of its structure in the course of diabetes mellitus. Moreover, we observed that HDL-6 subfraction and intermediate HDL fraction are lowest in the group with advanced DMt2 compared to the group with newly diagnosed DM and a healthy control group. Finally, the results of our study indicated the effect of statin treatment on HDL subfractions that seems not to be advantageous. Conclusion: It seems that in patients with diabetes mellitus compromised antiatherogenic properties of HDL, as a result of oxidative modification and glycation of the HDL protein as well as the transformation of the HDL proteome into a proinflammatory protein, increase cardiovascular risk.


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