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We studied the electrodermal skin conductance responses (SCRs) of 36 subjects with well-characterized lesions in various regions of the cerebral hemispheres. Several lesion loci were consistently associated with defective electrodermal responding: the ventromedial frontal region (right and left), the right inferior parietal region, and the anterior cingulate gyrus (right and left). Our findings provide direct information regarding neural correlates of skin conductance responses in bumans. [ABSTRACT FROM AUTHOR]

Recent water maze experiments suggest that rats performing place navigation primarily use the geometric information provided by a set of landmarks, and neglect the featural information provided by the identities of the landmarks. Here, I develop a model that explains how an animal may perform place navigation by relying only on geometric information. The core of the model is the representation of places as panoramas defined by circular bar-codes embodying the relative bearings and apparent sizes of the landmarks, irrespective of their identities. There are two stages in the model. During the first stage, the animal freely explores its environment in order to acquire spatial information at the local level. During the second stage, the animal uses the information previously memorized to perform place navigation towards the goal it intends to reach. The possible role of two brain areas in place navigation is discussed within this framework. Beyond their primary role in landmark-based representations of places, hippocampal place cells may be involved in computing the current distances to the landmarks. Beyond their primary role in landmark-based representations of headings, post-subicular head-direction cells may be involved in computing the “compass bearings” of the landmarks. [ABSTRACT FROM AUTHOR]

Selective attention, the ability to filter relevant from a sea of sensory information, relies on the prioritization of goal-relevant information (target facilitation) and the suppression of goal-irrelevant information (distractor suppression). Although several lines of evidence have shown that target facilitation and distractor suppression were mediated by distinct mechanisms, the underlying neural substrates remain unclear. To address this question, we acquired structural and resting-state magnetic resonance imaging scans, as well as behavioral data from a modified Posner cueing task. Specifically, the location of a target (Target Cue, TC) and a distractor (Distractor Cue, DC) was either cued in advance to separately trigger target facilitation and distractor suppression, or no predictive information was provided, serving as a baseline. We combined voxel-based morphometry (VBM) and resting-state functional connectivity (rsFC) analyses to explore the neural correlates of behavioral benefits, yielding the following results. First, behavioral data showed faster responses to TC and DC conditions compared to baseline, the benefits of which were named TC-benefit and DC-benefit. Second, the VBM analysis revealed that the gray matter volume (GMV) in the superior frontal (SFG) and postcentral gyrus inversely correlated with individual TC-benefit, while the GMV in the superior parietal lobe, middle frontal gyrus, and angular gyrus inversely correlated with individual DC-benefit, indicating that target facilitation and distractor suppression was associated with the GMV of distinct and distributed regions in the frontoparietal cortex. Third, the rsFC analysis with the SFG as a seed region further found distinct patterns of rsFC for target facilitation and distractor suppression. Specifically, individual TC-benefit were positively correlated with distributed connections between the SFG and brain regions, mainly within the ventral attention and somato-motor network; but individual DC-benefit were positively correlated with centralized connections between the SFG and brain regions, mainly within the frontoparietal, dorsal attention and ventral attention network. Finally, a multiple linear regression analysis showed that the GMV and rsFC could jointly explain individual differences in TC- and DC-benefit. Taken together, these results provided neural evidence for different structural and functional substrates underlying target facilitation and distractor suppression. ∙ Location cue of a distractor or target quickened search responses (DC/TC-benefit). ∙Neural substrates of DC/TC-benefit were explored using VBM and rsFC analyses. ∙Both GMV and rsFC analysis revealed distinct neural correlates of DC/TC-benefit. ∙GMV and rsFC together explained over 80% of individual variations in DC/TC-benefit. [ABSTRACT FROM AUTHOR]

Female mate choice is a dynamic process that allows individuals to selectively mate with those of the opposite sex that display a preferred set of traits. Because in many species males compete with each other for fertilization opportunities, female mate choice can be a powerful agent of sexual selection, often resulting in highly conspicuous traits in males. Although the evolutionary causes and consequences of the ornamentation and behaviors displayed by males to attract mates have been well studied, embarrassingly little is known about the proximate neural mechanisms through which female choice occurs. In vertebrates, female mate choice is inherently a social behavior, and although much remains to be discovered about this process, recent evidence suggests the neural substrates and circuits underlying other fundamental social behaviors (such as pair bonding, aggression and parental care) are likely similarly recruited during mate choice. Notably, female mate choice is not static, as social and ecological environments can shape the brain and, consequently, behavior in specific ways. In this Review, we discuss how social and/or ecological influences mediate female choice and how this occurs within the brain. We then discuss our current understanding of the neural substrates underlying female mate choice, with a specific focus on those that also play a role in regulating other social behaviors. Finally, we propose several promising avenues for future research by highlighting novel model systems and new methodological approaches, which together will transform our understanding of the causes and consequences of female mate choice., Competing Interests: Competing interestsThe authors declare no competing or financial interests., (© 2020. Published by The Company of Biologists Ltd.)

• The Cg1, IL, PrL, BLA, NAc, and DG probably mediated the paradoxical effect—reward and aversion. • Rewarding and aversive neural substrates involve in methamphetamine's conditioned suppression. • Our data conflict the reward comparison but support the paradoxical effect hypothesis of abused drugs. • The findings provide some clinical insights for drug addiction. Clinical studies of drug addiction focus on the reward impact of abused drugs that produces compulsive drug-seeking behavior and drug dependence. However, a small amount of research has examined the opposite effect of aversion to abused drugs to balance the reward effect for drug taking. An aversive behavioral model of abused drugs in terms of conditioned taste aversion (CTA) was challenged by the reward comparison hypothesis (Grigson, 1997). To test the reward comparison hypothesis, the present study examined the rewarding or aversive neural substrates involved in methamphetamine-induced conditioned suppression. The behavioral data showed that methamphetamine induced conditioned suppression on conditioning and reacquisition but extinguished it on extinction. A higher level of stressful aversive corticosterone occurred on conditioning and reacquisition but not extinction. The c-Fos or p-ERK immunohistochemical activity showed that the cingulated cortex area 1 (Cg1), infralimbic cortex (IL), prelimbic cortex (PrL), basolateral amygdala (BLA), nucleus accumbens (NAc), and dentate gyrus (DG) of the hippocampus were overexpressed in aversive CTA induced by methamphetamine. These data may indicate that the Cg1, IL, PrL, BLA, NAc, and DG probably mediated the paradoxical effect—reward and aversion. Altogether, our data conflicted with the reward comparison hypothesis, and methamphetamine may simultaneously induce the paradoxical effect of reward and aversion in the brain to support the paradoxical effect hypothesis of abused drugs. The present data implicate some insights for drug addiction in clinical aspects. [ABSTRACT FROM AUTHOR]

Summary Animals use sensory information to move toward more favorable conditions. Drosophila larvae can move up or down gradients of odors (chemotax), light (phototax), and temperature (thermotax) by modulating the probability, direction, and size of turns based on sensory input. Whether larvae can anemotax in gradients of mechanosensory cues is unknown. Further, although many of the sensory neurons that mediate taxis have been described, the central circuits are not well understood. Here, we used high-throughput, quantitative behavioral assays to demonstrate Drosophila larvae anemotax in gradients of wind speeds and to characterize the behavioral strategies involved. We found that larvae modulate the probability, direction, and size of turns to move away from higher wind speeds. This suggests that similar central decision-making mechanisms underlie taxis in somatosensory and other sensory modalities. By silencing the activity of single or very few neuron types in a behavioral screen, we found two sensory (chordotonal and multidendritic class III) and six nerve cord neuron types involved in anemotaxis. We reconstructed the identified neurons in an electron microscopy volume that spans the entire larval nervous system and found they received direct input from the mechanosensory neurons or from each other. In this way, we identified local interneurons and first- and second-order subesophageal zone (SEZ) and brain projection neurons. Finally, silencing a dopaminergic brain neuron type impairs anemotaxis. These findings suggest that anemotaxis involves both nerve cord and brain circuits. The candidate neurons and circuitry identified in our study provide a basis for future detailed mechanistic understanding of the circuit principles of anemotaxis. Graphical Abstract Highlights • Drosophila larvae perform negative anemotaxis • To anemotax, larvae modulate the turn rate, size, and direction as in other taxis • Chordotonal and multidendritic class III sensory neurons together mediate anemotaxis • The anemotactic circuitry involves both the nerve cord and the brain Jovanic et al. use high-throughput quantitative behavioral analysis, manipulation of neuronal activity, and EM reconstruction of neuronal connectivity to characterize Drosophila larva anemotactic behavior and identify two types of sensory neurons, six nerve cord neurons, and a brain dopaminergic neuron cluster all implicated in anemotaxis. [ABSTRACT FROM AUTHOR]

Summary Sparse manipulation of neuron excitability during free behavior is critical for identifying neural substrates of behavior. Genetic tools for precise neuronal manipulation exist in the fruit fly, Drosophila melanogaster , but behavioral tools are still lacking to identify potentially subtle phenotypes only detectible using high-throughput and high spatiotemporal resolution. We developed three assay components that can be used modularly to study natural and optogenetically induced behaviors. FlyGate automatically releases flies one at a time into an assay. FlyDetect tracks flies in real time, is robust to severe occlusions, and can be used to track appendages, such as the head. GlobeDisplay is a spherical projection system covering the fly's visual receptive field with a single projector. We demonstrate the utility of these components in an integrated system, FlyPEZ, by comprehensively modeling the input-output function for directional looming-evoked escape takeoffs and describing a millisecond-timescale phenotype from genetic silencing of a single visual projection neuron type. Graphical Abstract Highlights • FlyGate automatically releases flies one at a time into an assay • FlyDetect tracks flies in real time and is robust to severe occlusions • GlobeDisplay is a panoramic spherical projection system that uses a single projector • FlyPEZ uses these tools to quantify natural and optogenetically induced behavior Williamson et al. developed a high-throughput device to automatically isolate individual flies and record their behavior with high-speed video. They demonstrate the system's utility for studying the Drosophila brain using modern genetic tools by discovering behavioral phenotypes that result from manipulation of small groups of neurons. [ABSTRACT FROM AUTHOR]

[This corrects the article DOI: 10.3389/fnins.2018.00951.].

Inhibition of action is involved in stopping a movement, as well as terminating unnecessary movement during performance of a behavior. The inhibition of single actions, known as response inhibition (Inhibition of the urge to respond before or after actions) has been widely investigated using the go/no-go task and stop signal task. However, few studies focused on phase and volition-related inhibition after an action has been initiated. Here, we used functional magnetic resonance imaging (fMRI) to investigate the neural correlates of planning and execution underlying the voluntary inhibition of ongoing action. We collected fMRI data while participants performed a continuous finger-tapping task involving voluntary and involuntary (externally directed) inhibition, and during the initiation of movement. The results revealed areas of significantly greater activation during the preparation of inhibition of an ongoing action during voluntary inhibition, compared with involuntary inhibition, in the supplementary (SMA) and pre-supplementary motor areas, dorsolateral prefrontal cortex, inferior frontal gyrus (IFG), inferior parietal lobe, bilateral globus pallidus/putamen, bilateral insula and premotor cortex. Focusing on the period of execution of inhibition of ongoing actions, an event-related fMRI analysis revealed significant activation in the SMA, middle cingulate cortex, bilateral insula, right IFG and inferior parietal cortex. Additional comparative analyses suggested that brain activation while participants were planning to inhibit an ongoing action was similar to that during planning to start an action, indicating that the same neural substrates of motor planning may be recruited even when an action is ongoing. The present finding that brain activation associated with inhibiting ongoing actions was compatible with that seen in response inhibition (urge to stop before/after actions) suggests that common inhibitory mechanisms for motor movement are involved in both actual and planned motor action, which makes our behavior keep going seamlessly.

Scope: Caffeine is one of the most frequently used psychoactive substances ingested mainly via beverage or food products. Major depressive disorder is a serious and devastating psychiatric disorder. Emerging evidence indicates that caffeine enhances the antidepressant-like activity of common antidepressant drugs in rodents. However, whether joint administration of low dose of caffeine enhances the antidepressant actions in depressed patients remains unclear., Methods and Results: A total of 95 male inpatients were assigned to three groups and were asked to take either caffeine (60, 120 mg) or placebo (soymilk powder) daily for 4 wk on the basis of their current antidepressant medications. Results showed that chronic supplementation with low dose of caffeine (60 mg) produced rapid antidepressant action by reduction of depressive scores. Furthermore, low dose of caffeine improved cognitive performance in depressed patients. However, caffeine did not affect sleep as measured by overnight polysomnography. Moreover, chronic caffeine consumption elicited inhibition of hypothalamic-pituitary-adrenal axis activation by normalization of salivary cortisol induced by Trier social stress test., Conclusions: These findings indicated the potential benefits of further implications of supplementary administration of caffeine to reverse the development of depression and enhance the outcome of antidepressants treatment in major depressive disorder., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Objectives: An important subset of patients with schizophrenia present clinically significant persistent negative symptoms (PNS). Identifying the neural substrates of PNS could help improve our understanding and treatment of these symptoms., Methods: This study included 64 non-affective first-episode of psychosis (FEP) patients and 60 healthy controls; 16 patients displayed PNS (i.e., at least one primary negative symptom at moderate or worse severity sustained for at least six consecutive months). Using voxel-based morphometry (VBM), we explored for gray matter differences between PNS and non-PNS patients; patient groups were also compared to controls. All comparisons were performed at p < 0.05, corrected for multiple comparisons., Results: PNS patients had smaller gray matter in the right frontal medial-orbital gyrus (extending into the inferior frontal gyrus) and right parahippocampal gyrus (extending into the fusiform gyrus) compared to non-PNS patients. Compared to controls, PNS patients had smaller gray matter in the right parahippocampal gyrus (extending into the fusiform gyrus and superior temporal gyrus); non-PNS patients showed no significant differences to controls., Conclusion: Neural substrates of PNS are evident in FEP patients. A better understanding of the neural etiology of PNS may encourage the search for new medications and/or alternative treatments to better help those affected.