32 research outputs found
Localized microstimulation of primate pregenual cingulate cortex induces negative decision-making
The pregenual anterior cingulate cortex (pACC) has been implicated in human anxiety disorders and depression, but the circuit-level mechanisms underlying these disorders are unclear. In healthy individuals, the pACC is involved in cost-benefit evaluation. We developed a macaque version of an approach-avoidance decision task used to evaluate anxiety and depression in humans and, with multi-electrode recording and cortical microstimulation, we probed pACC function as monkeys performed this task. We found that the macaque pACC has an opponent process-like organization of neurons representing motivationally positive and negative subjective value. Spatial distribution of these two neuronal populations overlapped in the pACC, except in one subzone, where neurons with negative coding were more numerous. Notably, microstimulation in this subzone, but not elsewhere in the pACC, increased negative decision-making, and this negative biasing was blocked by anti-anxiety drug treatment. This cortical zone could be critical for regulating negative emotional valence and anxiety in decision-making.National Institutes of Health (U.S.) (Javits Merit Grant R01 NS025529)United States. Office of Naval Research (N000140710903)National Parkinson Foundation (U.S.) (Lynn Diamond Fellowship
Validation of the theoretical domains framework for use in behaviour change and implementation research
Background
An integrative theoretical framework, developed for cross-disciplinary implementation and other behaviour change research, has been applied across a wide range of clinical situations. This study tests the validity of this framework.
Methods
Validity was investigated by behavioural experts sorting 112 unique theoretical constructs using closed and open sort tasks. The extent of replication was tested by Discriminant Content Validation and Fuzzy Cluster Analysis.
Results
There was good support for a refinement of the framework comprising 14 domains of theoretical constructs (average silhouette value 0.29): 'Knowledge', 'Skills', 'Social/Professional Role and Identity', 'Beliefs about Capabilities', 'Optimism', 'Beliefs about Consequences', 'Reinforcement', 'Intentions', 'Goals', 'Memory, Attention and Decision Processes', 'Environmental Context and Resources', 'Social Influences', 'Emotions', and 'Behavioural Regulation'.
Conclusions
The refined Theoretical Domains Framework has a strengthened empirical base and provides a method for theoretically assessing implementation problems, as well as professional and other health-related behaviours as a basis for intervention development
Goal-oriented searching mediated by ventral hippocampus early in trial-and-error learning
Most behavioral learning in biology is trial and error, but how these learning processes are influenced by individual brain systems is poorly understood. Here we show that ventral-to-dorsal hippocampal subdivisions have specific and sequential functions in trial-and-error maze navigation, with ventral hippocampus (vH) mediating early task-specific goal-oriented searching. Although performance and strategy deployment progressed continuously at the population level, individual mice showed discrete learning phases, each characterized by particular search habits. Transitions in learning phases reflected feedforward inhibitory connectivity (FFI) growth occurring sequentially in ventral, then intermediate, then dorsal hippocampal subdivisions. FFI growth at vH occurred abruptly upon behavioral learning of goal-task relationships. vH lesions or the absence of vH FFI growth delayed early learning and disrupted performance consistency. Intermediate hippocampus lesions impaired intermediate place learning, whereas dorsal hippocampus lesions specifically disrupted late spatial learning. Trial-and-error navigational learning processes in naive mice thus involve a stereotype sequence of increasingly precise subtasks learned through distinct hippocampal subdivisions. Because of its unique connectivity, vH may relate specific goals to internal states in learning under healthy and pathological conditions
Striatum-Centered Fiber Connectivity Is Associated with the Personality Trait of Cooperativeness
Cooperativeness is an essential behavioral trait evolved to facilitate group living. Social and cognitive mechanisms involved in cooperation (e.g., motivation, reward encoding, action evaluation, and executive functions) are sub-served by the striatal-projected circuits, whose physical existence has been confirmed by animal studies, human postmortem studies, and in vivo human brain studies. The current study investigated the associations between Cooperativeness and fiber connectivities from the striatum to nine subcortical and cortical regions, including the amygdala, hippocampus, medial orbitofrontal cortex, lateral orbitofrontal cortex, ventrolateral prefrontal cortex, dorsolateral prefrontal cortex, posterior cingulate cortex/retrosplenial cortex, dorsal cingulate cortex, and rostral cingulate cortex. Results showed that Cooperativeness was negatively correlated with fiber connectivity for the cognitive control system (from the dorsal caudate to the rostral cingulate cortex and ventrolateral prefrontal cortex), but not with fiber connectivity for the social cognitive system (e.g., connectivity with the medial prefrontal cortex and amygdala). These results partially supported Declerck et al.'s (2013) cognitive neural model of the role of cognitive control and social cognition in cooperation