Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
DisciplineDiscipline
-
Is Peer ReviewedIs Peer Reviewed
-
Item TypeItem Type
-
SubjectSubject
-
YearFrom:-To:
-
More FiltersMore FiltersSourceLanguage
Done
Filters
Reset
1,553
result(s) for
"Dolan, R."
Sort by:
Emotion, Cognition, and Behavior
2002
Emotion is central to the quality and range of everyday human experience. The neurobiological substrates of human emotion are now attracting increasing interest within the neurosciences motivated, to a considerable extent, by advances in functional neuroimaging techniques. An emerging theme is the question of how emotion interacts with and influences other domains of cognition, in particular attention, memory, and reasoning. The psychological consequences and mechanisms underlying the emotional modulation of cognition provide the focus of this article.
Journal Article
Depression is related to an absence of optimistically biased belief updating about future life events
by
Walter, H.
,
Heekeren, H. R.
,
Dolan, R. J.
in
Adult
,
Adult and adolescent clinical studies
,
Analysis of Variance
2014
When challenged with information about the future, healthy participants show an optimistically biased updating pattern, taking desirable information more into account than undesirable information. However, it is unknown how patients suffering from major depressive disorder (MDD), who express pervasive pessimistic beliefs, update their beliefs when receiving information about their future. Here we tested whether an optimistically biased information processing pattern found in healthy individuals is absent in MDD patients.
MDD patients (n = 18; 13 medicated; eight with co-morbid anxiety disorder) and healthy controls (n = 19) estimated their personal probability of experiencing 70 adverse life events. After each estimate participants were presented with the average probability of the event occurring to a person living in the same sociocultural environment. This information could be desirable (i.e. average probability better than expected) or undesirable (i.e. average probability worse than expected). To assess how desirable versus undesirable information influenced beliefs, participants estimated their personal probability of experiencing the 70 events a second time.
Healthy controls showed an optimistic bias in updating, that is they changed their beliefs more toward desirable versus undesirable information. Overall, this optimistic bias was absent in MDD patients. Symptom severity correlated with biased updating: more severely depressed individuals showed a more pessimistic updating pattern. Furthermore, MDD patients estimated the probability of experiencing adverse life events as higher than healthy controls.
Our findings raise the intriguing possibility that optimistically biased updating of expectations about one's personal future is associated with mental health.
Journal Article
Adolescent friendships predict later resilient functioning across psychosocial domains in a healthy community cohort
2017
Adolescence is a key time period for the emergence of psychosocial and mental health difficulties. To promote adolescent adaptive ('resilient') psychosocial functioning (PSF), appropriate conceptualisation and quantification of such functioning and its predictors is a crucial first step. Here, we quantify resilient functioning as the degree to which an individual functions better or worse than expected given their self-reported childhood family experiences, and relate this to adolescent family and friendship support.
We used Principal Component and regression analyses to investigate the relationship between childhood family experiences and PSF (psychiatric symptomatology, personality traits and mental wellbeing) in healthy adolescents (the Neuroscience in Psychiatry Network; N = 2389; ages 14-24). Residuals from the relation between childhood family experiences and PSF reflect resilient functioning; the degree to which an individual is functioning better, or worse, than expected given their childhood family experiences. Next, we relate family and friendship support with resilient functioning both cross-sectionally and 1 year later.
Friendship and family support were positive predictors of immediate resilient PSF, with friendship support being the strongest predictor. However, whereas friendship support was a significant positive predictor of later resilient functioning, family support had a negative relationship with later resilient PSF.
We show that friendship support, but not family support, is an important positive predictor of both immediate and later resilient PSF in adolescence and early adulthood. Interventions that promote the skills needed to acquire and sustain adolescent friendships may be crucial in increasing adolescent resilient PSF.
Journal Article
Per Theodor Cleve (1840-1905): The Prolific Part-Time Protistologist and Oceanographer
2025
Per Theodor Cleve is known as a 19th century chemist, credited with discovery of two rare-earth elements. However, throughout his distinguished career as a chemist, he was also a protistologist. From 1863 to 1905, Cleve published prodigiously on protists, authoring over 70 works totaling about 2,500 pages, and he described numerous taxa, especially from the marine plankton. Notably, many of Cleve's works are still cited today. His work concerning the utility of certain protist species in characterizing water masses has been recognized in histories of Oceanography. However, Cleve is not a familiar name to many of us, as he has been consistently overlooked in histories of protistology. Here, first Cleve's life is summarized, and then his contributions to protistology, and oceanography, are reviewed to show his significant, and neglected, contributions to the fields.
Journal Article
Increased fronto-striatal reward prediction errors moderate decision making in obsessive–compulsive disorder
2017
Obsessive-compulsive disorder (OCD) has been linked to functional abnormalities in fronto-striatal networks as well as impairments in decision making and learning. Little is known about the neurocognitive mechanisms causing these decision-making and learning deficits in OCD, and how they relate to dysfunction in fronto-striatal networks.
We investigated neural mechanisms of decision making in OCD patients, including early and late onset of disorder, in terms of reward prediction errors (RPEs) using functional magnetic resonance imaging. RPEs index a mismatch between expected and received outcomes, encoded by the dopaminergic system, and are known to drive learning and decision making in humans and animals. We used reinforcement learning models and RPE signals to infer the learning mechanisms and to compare behavioural parameters and neural RPE responses of the OCD patients with those of healthy matched controls.
Patients with OCD showed significantly increased RPE responses in the anterior cingulate cortex (ACC) and the putamen compared with controls. OCD patients also had a significantly lower perseveration parameter than controls.
Enhanced RPE signals in the ACC and putamen extend previous findings of fronto-striatal deficits in OCD. These abnormally strong RPEs suggest a hyper-responsive learning network in patients with OCD, which might explain their indecisiveness and intolerance of uncertainty.
Journal Article
Computational neuroimaging strategies for single patient predictions
by
Dolan, R.J.
,
Brodersen, K.H.
,
Schlagenhauf, F.
in
Attention deficit hyperactivity disorder
,
Bayesian
,
Brain Diseases - diagnostic imaging
2017
Neuroimaging increasingly exploits machine learning techniques in an attempt to achieve clinically relevant single-subject predictions. An alternative to machine learning, which tries to establish predictive links between features of the observed data and clinical variables, is the deployment of computational models for inferring on the (patho)physiological and cognitive mechanisms that generate behavioural and neuroimaging responses. This paper discusses the rationale behind a computational approach to neuroimaging-based single-subject inference, focusing on its potential for characterising disease mechanisms in individual subjects and mapping these characterisations to clinical predictions. Following an overview of two main approaches – Bayesian model selection and generative embedding – which can link computational models to individual predictions, we review how these methods accommodate heterogeneity in psychiatric and neurological spectrum disorders, help avoid erroneous interpretations of neuroimaging data, and establish a link between a mechanistic, model-based approach and the statistical perspectives afforded by machine learning.
•Reviews computational neuroimaging strategies for single patient predictions.•Generative models for inferring individual disease mechanisms in psychiatry and neurology.•Mapping inferred mechanisms to clinical predictions by Bayesian model selection and•generative embedding.•Links a mechanistic model-based approach to statistical perspectives by machine learning.
Journal Article
Optimistic update bias increases in older age
2014
Healthy older adults report greater well-being and life satisfaction than their younger counterparts. One potential explanation for this is enhanced optimism. We tested the influence of age on optimistic and pessimistic beliefs about the future and the associated structural neural correlates.
Eighteen young and 18 healthy older adults performed a belief updating paradigm, measuring differences in updating beliefs for desirable and undesirable information about future negative events. These measures were related to regional brain volume, focusing on the anterior cingulate cortex (ACC) because this region is strongly linked to a positivity bias in older age.
We demonstrate an age-related reduction in updating beliefs when older adults are faced with undesirable, but not desirable, information about negative events. This greater 'update bias' in older age persisted even after controlling for a variety of variables including subjective rating scales and poorer overall memory. A structural brain correlate of this greater 'update bias' was evident in greater grey matter volume in the dorsal ACC in older but not in young adults.
We show a greater update bias in healthy older age. The link between this bias and relative volume of the ACC suggests a shared mechanism with an age-related positivity bias. Older adults frequently have to make important decisions relating to personal, health and financial issues. Our findings have wider behavioural implications in these contexts because an enhanced optimistic update bias may skew such real-world decision making.
Journal Article
The human amygdala and orbital prefrontal cortex in behavioural regulation
Survival in complex environments depends on an ability to optimize future behaviour based on past experience. Learning from experience enables an organism to generate predictive expectancies regarding probable future states of the world, enabling deployment of flexible behavioural strategies. However, behavioural flexibility cannot rely on predictive expectancies alone and options for action need to be deployed in a manner that is responsive to a changing environment. Important moderators on learning-based predictions include those provided by context and inputs regarding an organism's current state, including its physiological state. In this paper, I consider human experimental approaches using functional magnetic resonance imaging that have addressed the role of the amygdala and prefrontal cortex (PFC), in particular the orbital PFC, in acquiring predictive information regarding the probable value of future events, updating this information, and shaping behaviour and decision processes on the basis of these value representations.
Journal Article
β-Adrenergic Modulation of Emotional Memory-Evoked Human Amygdala and Hippocampal Responses
by
Strange, B. A.
,
Dolan, R. J.
,
McGaugh, James L.
in
Adrenergic beta-Antagonists - administration & dosage
,
Adult
,
Amygdala
2004
Human emotional experience is typically associated with enhanced episodic memory. We have used functional magnetic resonance imaging to demonstrate that successful encoding of emotional, compared to neutral, verbal stimuli evokes increased human amygdala responses. Items that evoke amygdala activation at encoding evoke greater hippocampal responses at retrieval compared to neutral items. Administration of the β-adrenergic antagonist propranolol at encoding abolishes the enhanced amygdala encoding and hippocampal retrieval effects, despite propranolol being no longer present at retrieval. Thus, memory-related amygdala responses at encoding and hippocampal responses at recognition for emotional items depend on β-adrenergic engagement at encoding. Our results suggest that human emotional memory is associated with a β-adrenergic-dependent modulation of amygdala-hippocampal interactions.
Journal Article
Tunable cavity coupling of the zero phonon line of a nitrogen-vacancy defect in diamond
2015
We demonstrate the tunable enhancement of the zero phonon line of a single nitrogen-vacancy colour centre in diamond at cryogenic temperature. An open cavity fabricated using focused ion beam milling provides mode volumes as small as 1.24 m3 (4.7 ) and quality factor In situ tuning of the cavity resonance is achieved with piezoelectric actuators. At optimal coupling to a TEM00 cavity mode, the signal from individual zero phonon line transitions is enhanced by a factor of 6.25 and the overall emission rate of the NV− centre is increased by 40% compared with that measured from the same centre in the absence of cavity field confinement. This result represents a step forward in the realisation of efficient spin-photon interfaces and scalable quantum computing using optically addressable solid state spin qubits.
Journal Article