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Prevalence, symptoms, and treatment of depression suggest that major depressive disorders (MDD) present sex differences. Social stress-induced neurovascular pathology is associated with depressive symptoms in male mice; however, this association is unclear in females. Here, we report that chronic social and subchronic variable stress promotes blood-brain barrier (BBB) alterations in mood-related brain regions of female mice. Targeted disruption of the BBB in the female prefrontal cortex (PFC) induces anxiety- and depression-like behaviours. By comparing the endothelium cell-specific transcriptomic profiling of the mouse male and female PFC, we identify several pathways and genes involved in maladaptive stress responses and resilience to stress. Furthermore, we confirm that the BBB in the PFC of stressed female mice is leaky. Then, we identify circulating vascular biomarkers of chronic stress, such as soluble E-selectin. Similar changes in circulating soluble E-selectin, BBB gene expression and morphology can be found in blood serum and postmortem brain samples from women diagnosed with MDD. Altogether, we propose that BBB dysfunction plays an important role in modulating stress responses in female mice and possibly MDD.

Difficulties in Facial Emotion Recognition (FER) are commonly associated with individuals diagnosed with Autism Spectrum Disorder (ASD). However, the mechanisms underlying these impairments remain inconclusive. While atypical cortical connectivity has been observed in autistic individuals, there is a paucity of investigation during cognitive tasks such as FER. It is possible that atypical cortical connectivity may underlie FER impairments in this population. Electroencephalography (EEG) Imaginary Coherence was examined in 22 autistic adults and 23 typically developing (TD) matched controls during a complex, dynamic FER task. Autistic adults demonstrated reduced coherence between both short and long range inter-hemispheric electrodes. By contrast, short range intra-hemispheric connectivity was increased in frontal and occipital regions during FER. These findings suggest altered network functioning in ASD.

Human fear is important in wildlife management, but self-reported fear provides only partial information about fear reactions. Thus, eye movements, skin conductance, and changes in heart rate were assessed during picture viewing, visual search, and implicit evaluation tasks. Pictures of bears, wolves, moose, and hares were presented to participants who self-reported as fearful of bears (n = 8), fearful of bears and wolves (n = 15), or not fearful of bears or wolves (n = 14). The feared animal was expected to elicit strong physiological responses, be dwelled upon, and be associated with negative words. Independent of fearfulness, bear pictures elicited the strongest physiological responses, and wolf pictures showed the strongest negative associations. The bear-fearful group showed stronger physiological responses to bears. The bear- and wolf-fearful group showed more difficulty in associating bears with good words. Presence of a feared animal in the search task, resulted in prolonged response time.

There is evidence that some atypical antipsychotics, including olanzapine, can produce unwanted metabolic side effects, weight gain and diabetes. However, neuronal correlates of change related to food information processing have not been investigated with these medications. We studied the effect of a pharmacological manipulation with an antipsychotic known to cause weight gain on metabolites, cognitive tasks and neural correlates related to food regulation. We used functional magnetic resonance imaging in conjunction with a task requiring visual processing of appetitive stimuli in schizophrenic patients and healthy controls before and after 16 weeks of antipsychotic medication with olanzapine. In patients, the psychological and neuronal changes associated following the treatment correlated with appetite control measures and metabolite levels in fasting blood samples. After 16 weeks of olanzapine treatment, the patients gained weight, increased their waist circumference, had fewer positive schizophrenia symptoms, a reduced ghrelin plasma concentration and an increased concentration of triglycerides, insulin and leptin. In premotor area, somatosensory cortices as well as bilaterally in the fusiform gyri, the olanzapine treatment increased the neural activity related to appetitive information in schizophrenic patients to similar levels relative to healthy individuals. However, a higher increase in sensitivity to appetitive stimuli after the treatment was observed in insular cortices, amygdala and cerebellum in schizophrenic patients as compared with healthy controls. Furthermore, these changes in neuronal activity correlated with changes in some metabolites and cognitive measurements related to appetite regulation.

Two experiments were conducted to assess simultaneously the effects of attentional and emotional processes on startle eyeblink modulation. In each experiment, participants were presented with a pleasant and an unpleasant picture. Half the participants were asked to attend to the pleasant picture and to ignore the unpleasant picture, whereas the reverse was the case for the other participants. Startle probes were presented at 3500 and 4500 ms after stimulus onset in Experiment 1 and at 250, 750, and 4450 ms after stimulus onset and 950 ms after stimulus offset in Experiment 2. Attentional processing affected startle eyeblink modulation and electrodermal responses in both experiments. However, effects of picture valence on startle eyeblink modulation were found only in Experiment 2. The results confirm the utility of startle eyeblink modulation as an index of attentional and emotional processing. They also illustrate that procedural characteristics, such as the nature of the lead intervals and how attention and emotion are operationalized, can determine whether emotional or attentional processes will be reflected in startle eyeblink.

The present research investigated blink startle modulation during the anticipation of pleasant, unpleasant, or neutral pictures. In Experiment 1 (N = 18), participants were presented with three different tone-picture pairings. Tones differed in pitch and were followed by pleasant, neutral or unpleasant pictures. Acoustic blink reflexes were elicited during some tones and during stimulus free intervals. Blink facilitation during tones that preceded pleasant and unpleasant pictures was larger than during the tone that preceded neutral pictures. Experiment 2 (N = 10) assessed whether this difference was due to a difference in the presentation frequency of the three conditions. No difference in blink facilitation between the conditions was found when pictures of flowers and mushrooms replaced the pleasant and unpleasant pictures, indicating that picture content was instrumental in causing the differential blink facilitation in Experiment 1. The results from Experiment 1 seem to indicate that startle modulation during the anticipation of pictorial material reflects the interest in or the arousal associated with the pictures rather than picture valence.

We used the startle eyeblink modification paradigm to investigate whether clinically anxious children, like high trait-anxious adults, display a bias in favour of threat words compared to neutral words. The present study included 16 clinically anxious children whose diagnostic status was determined using the parent version of a semistructured diagnostic interview as part of a larger childhood anxiety study. The children were presented with threat and neutral words for 6 s each. A startle-eliciting auditory stimulus - a 100 dBA burst of white noise of 50 ms duration - was presented during the words at lead intervals of 60, 120, 240, or 3500 ms and during intertrial intervals. The overall pattern of startle eyeblink modification indicated inhibition at the 120 and 240 ms lead intervals and facilitation at the 3500 ms lead interval. Startle-latency shortening during threat words at the 60 ms lead interval was larger than at other intervals, whereas there was no difference during neutral words. This result reflects an anxiety-related bias in favour of threat words occurring at a very early - and possibly preattentive stage - of information processing.

The present study examined the effects of task-relevance of an habituation stimulus and intermodality change on electrodermal responses and on secondary task probe reaction time. In experimental conditions, subjects received 24 presentations of either a tone or a vibrotactile stimulus followed by one presentation of a stimulus From the other modality. Subjects in control conditions received 25 presentations of a tone or a vibration. Within each of these conditions, half the subjects were required to count the number of longer-than-usual stimuli which occurred with a probability of.25. Secondary task probes consisted of a visual stimulus of 500ms duration which, during habituation training, was presented 150, 300 or 600ms following stimulus onset and during some of the inter stimulus intervals. Trial 25 contained a probe at the 300ms position. The results indicated that skin conductance responses were not only larger on trial 25 in the experimental condition than in the control, but that they were larger than during the first half of the habituation series. In addition, reaction time was slower to within-stimulus probes in the task-relevant condition than to those presented in the task-irrelevant condition; was slower on trial 25 in the experimental condition than in the control, and, in the experimental condition, was slower on trial 25 than during the first half of the habituation series. The data are consistent with an information processing approach to orienting and habituation and appear to pose problems for non-comparator theories of habituation.

The present study was designed to elicit response differentiation by conditional tonic (contextual) and phasic stimuli, using a differential compound conditioning paradigm. Sixteen borderline hypertensives (BH) and sixteen normotensives (NT) served as subjects. A tone (400 Hz, 70 dBA) lasting for eight seconds was the phasic conditional stimulus. Illuminations of the subjects' room differing in color (blue and yellow respectively) served as tonic stimuli (two minutes duration each). While the tonic stimulus was present only one phasic stimulus was given. During acquisition phase, this stimulus was reinforced by the unconditional stimulus (US, electric stimulation) in one context, whereas it was not in the other one. During extinction, no US was given. Skin conductance (SC), heart rate (HR), and forearm bloodflow (FBF) were the dependent variables to be conditioned. In both groups, conditional responses could be obtained for phasic changes in SC and HR. FBF was reliably conditioned by tonic stimulation (context) in BH only. In addition, BH showed stronger SC activity (more non-specific SC responses, higher SC level) than NT. did.