Hippocampal and medial prefrontal ensemble spiking represents episodes and rules in similar task spaces.

Episodic memory requires the hippocampus and prefrontal cortex to guide decisions by representing events in spatial, temporal, and personal contexts. Both brain regions have been described by cognitive theories that represent events in context as locations in maps or memory spaces. We query whether ensemble spiking in these regions described spatial structures as rats performed memory tasks.

Hippocampal and Medial Prefrontal Cortex Fractal Spiking Patterns Encode Episodes and Rules.

A central question in neuroscience is how the brain represents and processes information to guide behavior. The principles that organize brain computations are not fully known, and could include scale-free, or fractal patterns of neuronal activity. Scale-free brain activity may be a natural consequence of the relatively small subsets of neuronal populations that respond to task features, i.

Goal Choices Modify Frontotemporal Memory Representations.

Adapting flexibly to changing circumstances is guided by memory of past choices, their outcomes in similar circumstances, and a method for choosing among potential actions. The hippocampus (HPC) is needed to remember episodes, and the prefrontal cortex (PFC) helps guide memory retrieval. Single-unit activity in the HPC and PFC correlates with such cognitive functions.

Hippocampal signals modify orbitofrontal representations to learn new paths.

We often remember the consequences of past choices to adapt to changing circumstances. Recalling past events requires the hippocampus (HPC), and using stimuli to anticipate outcome values requires the orbitofrontal cortex (OFC). Spatial reversal tasks require both structures to navigate newly rewarded paths.

An in silico model for determining the influence of neuronal co-activity on rodent spatial behavior.

Background: Neuropsychological and neurophysiological analyses focus on understanding how neuronal activity and co-activity predict behavior. Experimental techniques allow for modulation of neuronal activity, but do not control neuronal ensemble spatiotemporal firing patterns, and there are few, if any, sophisticated in silico techniques which accurately reconstruct physiological neural spike trains and behavior using unit co-activity as an input parameter.

New Method: Our approach to simulation of neuronal spike trains is based on using state space modeling to estimate a weighted graph of interaction strengths between pairs of neurons along with separate estimations of spiking threshold voltage and neuronal membrane leakage.

Medial Prefrontal Cortex Reduces Memory Interference by Modifying Hippocampal Encoding.

The prefrontal cortex (PFC) is crucial for accurate memory performance when prior knowledge interferes with new learning, but the mechanisms that minimize proactive interference are unknown. To investigate these, we assessed the influence of medial PFC (mPFC) activity on spatial learning and hippocampal coding in a plus maze task that requires both structures. mPFC inactivation did not impair spatial learning or retrieval per se, but impaired the ability to follow changing spatial rules.

Basal forebrain projections to the lateral habenula modulate aggression reward.

Maladaptive aggressive behaviour is associated with a number of neuropsychiatric disorders and is thought to result partly from the inappropriate activation of brain reward systems in response to aggressive or violent social stimuli. Nuclei within the ventromedial hypothalamus, extended amygdala and limbic circuits are known to encode initiation of aggression; however, little is known about the neural mechanisms that directly modulate the motivational component of aggressive behaviour. Here we established a mouse model to measure the valence of aggressive inter-male social interaction with a smaller subordinate intruder as reinforcement for the development of conditioned place preference (CPP).

In vivo imaging identifies temporal signature of D1 and D2 medium spiny neurons in cocaine reward.

The reinforcing and rewarding properties of cocaine are attributed to its ability to increase dopaminergic transmission in nucleus accumbens (NAc). This action reinforces drug taking and seeking and leads to potent and long-lasting associations between the rewarding effects of the drug and the cues associated with its availability. The inability to extinguish these associations is a key factor contributing to relapse.

Excitatory transmission at thalamo-striatal synapses mediates susceptibility to social stress.

Postsynaptic remodeling of glutamatergic synapses on ventral striatum (vSTR) medium spiny neurons (MSNs) is critical for shaping stress responses. However, it is unclear which presynaptic inputs are involved. Susceptible mice exhibited increased synaptic strength at intralaminar thalamus (ILT), but not prefrontal cortex (PFC), inputs to vSTR MSNs following chronic social stress.

Involvement of the anterior cingulate and frontoinsular cortices in rapid processing of salient facial emotional information.

The anterior cingulate cortex (ACC) and frontoinsular cortex (FI) have been implicated in processing information across a variety of domains, including those related to attention and emotion. However, their role in rapid information processing, for example, as required for timely processing of salient stimuli, is not well understood. Here, we designed an emotional face priming paradigm and employed functional magnetic resonance imaging to elucidate their role in these mechanisms.

Genetics as a tool for the dissociation of mental operations over the course of development.

In recent years it has become possible to differentiate separable aspects of attention and to characterize the anatomical structure and dynamic states of their underlying networks. When individual differences in the structure and dynamics of these networks are used as dependent measures in associations with individual genetic variation, it becomes possible to assign cellular and molecular changes that occur over the course of normal development to specific aspects of network structure and function. In this way, a more granular understanding of the physiology of neural networks can be obtained.

Neural correlates of using distancing to regulate emotional responses to social situations.

Cognitive reappraisal is a commonly used and highly adaptive strategy for emotion regulation that has been studied in healthy volunteers. Most studies to date have focused on forms of reappraisal that involve reinterpreting the meaning of stimuli and have intermixed social and non-social emotional stimuli. Here we examined the neural correlates of the regulation of negative emotion elicited by social situations using a less studied form of reappraisal known as distancing.

Functional dissociation of the frontoinsular and anterior cingulate cortices in empathy for pain.

The frontoinsular cortex (FI) and the anterior cingulate cortex (ACC) are thought to be involved in empathy for others' pain. However, the functional roles of FI and ACC in empathetic responses have not yet been clearly dissociated in previous studies. In this study, participants viewed color photographs depicting human body parts in painful or nonpainful situations and performed either pain judgment (painful/nonpainful) or laterality judgment (left/right) of the body parts.

Neural correlates of the use of psychological distancing to regulate responses to negative social cues: a study of patients with borderline personality disorder.

Background: Emotional instability is a defining feature of borderline personality disorder (BPD); yet, little is understood about its underlying neural correlates. One possible contributing factor to emotional instability is a failure to adequately employ adaptive cognitive regulatory strategies such as psychological distancing.

Methods: To determine whether there are differences in neural dynamics underlying this control strategy between BPD patients and healthy control (HC) subjects, blood oxygenation level-dependent (BOLD) functional magnetic resonance imaging signals were acquired as 18 BPD and 16 HC subjects distanced from or simply looked at pictures depicting social interactions.

A functional magnetic resonance imaging study of deliberate emotion regulation in resilience and posttraumatic stress disorder.

Background: Sexual violence is an important public health problem in the United States, with 13% to 26% of women reporting a history of sexual assault. While unfortunately common, there is substantial individual variability in response to sexual assault. Approximately half of rape victims develop posttraumatic stress disorder (PTSD), while others develop no psychopathology (e.

Effective connectivity of the fronto-parietal network during attentional control.

The ACC, the dorsolateral prefrontal cortex (DLPFC), and the parietal cortex near/along the intraparietal sulcus (IPS) are members of a network subserving attentional control. Our recent study revealed that these regions participate in both response anticipation and conflict processing. However, little is known about the relative contribution of these regions in attentional control and how the dynamic interactions among these regions are modulated by detection of predicted versus unpredicted targets and conflict processing.

Testing the behavioral interaction and integration of attentional networks.

One current conceptualization of attention subdivides it into functions of alerting, orienting, and executive control. Alerting describes the function of tonically maintaining the alert state and phasically responding to a warning signal. Automatic and voluntary orienting are involved in the selection of information among multiple sensory inputs.

Alexithymic trait and voluntary control in healthy adults.

Background: Alexithymia is a personality trait characterized by deficiency in understanding, processing, or describing emotions. Recent studies have revealed that alexithymia is associated with less activation of the anterior cingulate cortex, a brain region shown to play a role in cognitive and emotional processing. However, few studies have directly investigated the cognitive domain in relation to alexithymia to examine whether alexithymic trait is related to less efficient voluntary control.

Searching for the majority: algorithms of voluntary control.

Voluntary control of information processing is crucial to allocate resources and prioritize the processes that are most important under a given situation; the algorithms underlying such control, however, are often not clear. We investigated possible algorithms of control for the performance of the majority function, in which participants searched for and identified one of two alternative categories (left or right pointing arrows) as composing the majority in each stimulus set. We manipulated the amount (set size of 1, 3, and 5) and content (ratio of left and right pointing arrows within a set) of the inputs to test competing hypotheses regarding mental operations for information processing.

Functional connectivity of the sensorimotor area in naturally sleeping infants.

Patterns of cortical functional connectivity in normal infants were examined during natural sleep by observing the time course of very low frequency oscillations. Such oscillations represent fluctuations in blood oxygenation level and cortical blood flow thus allowing computation of neurophysiologic connectivity. Structural and resting-state information were acquired for 11 infants, with a mean age of 12.

Provisional hypotheses for the molecular genetics of cognitive development: imaging genetic pathways in the anterior cingulate cortex.

Brain imaging genetic research involves a multitude of methods and spans many traditional levels of analysis. Given the vast permutations among several million common genetic variants with thousands of brain tissue voxels and a wide array of cognitive tasks that activate specific brain systems, we are prompted to develop specific hypotheses that synthesize converging evidence and state clear predictions about the anatomical sources, magnitude and direction (increases vs. decreases) of allele- and task-specific brain activity associations.

The functional integration of the anterior cingulate cortex during conflict processing.

Although functional activation of the anterior cingulate cortex (ACC) related to conflict processing has been studied extensively, the functional integration of the subdivisions of the ACC and other brain regions during conditions of conflict is still unclear. In this study, participants performed a task designed to elicit conflict processing by using flanker interference on target response while they were scanned using event-related functional magnetic resonance imaging. The physiological response of several brain regions in terms of an interaction between conflict processing and activity of the anterior rostral cingulate zone (RCZa) of the ACC, and the effective connectivity between this zone and other regions were examined using psychophysiological interaction analysis and dynamic causal modeling, respectively.

The relation of brain oscillations to attentional networks.

Previous studies have suggested the relation of particular frequency bands such as theta (4-8 Hz), alpha (8-14 Hz), beta (14-30 Hz), or gamma (>30 Hz) to cognitive functions. However, there has been controversy over which bands are specifically related to attention. We used the attention network test to separate three anatomically defined brain networks that carry out the functions of alerting, orienting, and executive control of attention.

The Anatomical and Evolutionary Relationship between Self-awareness and Theory of Mind.

Although theories that examine direct links between behavior and brain remain incomplete, it is known that brain expansion significantly correlates with caloric and oxygen demands. Therefore, one of the principles governing evolutionary cognitive neuroscience is that cognitive abilities that require significant brain function (and/or structural support) must be accompanied by significant fitness benefit to offset the increased metabolic demands. One such capacity is self-awareness (SA), which (1) is found only in the greater apes and (2) remains unclear in terms of both cortical underpinning and possible fitness benefit.