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Displaying a stress response to threatening stimuli is essential for survival. These reactions must be adjusted to be adaptive. Otherwise, even mental illnesses may develop. Describing the physiological stress response may contribute to distinguishing the abnormal responses that accompany the pathology, which may help to improve the development of both diagnoses and treatments. Recent advances have elucidated many of the processes and structures involved in stress response management; however, there is still much to unravel regarding this phenomenon. The main aim of the present research is to characterize the response of three brain areas deeply involved in the stress response (i.e., to an acute stressful experience). Specifically, the electrophysiological activity of the infralimbic division of the medial prefrontal cortex (IL), the basolateral nucleus of the amygdala (BLA), and the dorsal hippocampus (dHPC) was recorded after the infusion of 0.5 µl of corticosterone-releasing factor into the dorsal raphe nucleus (DRN), a procedure which has been validated as a paradigm to cause acute stress. This procedure induced a delayed reduction in slow waves in the three structures, and an increase in faster oscillations, such as those in theta, beta, and gamma bands. The mutual information at low theta frequencies between the BLA and the IL increased, and the delta and slow wave mutual information decreased. The low theta–mid gamma phase–amplitude coupling increased within BLA, as well as between BLA and IL. This electrical pattern may facilitate the activation of these structures, in response to the stressor, and memory consolidation.

The stress system coordinates the adaptive responses of the organism to stressors of any kind. Dysfunction in this circuit may induce disturbances in emotional and cognitive aspects of several stress-related pathologies including depression. Thus, comprehension of dynamics and communication between these structures may lead to better understand neurobiological mechanism underlying anxiety disorders and also the beneficial effects of some treatments, such as deep brain stimulation (DBS). The main purpose of this work is to delve into interactions between several of the structures related to stress control evaluating changes in their oscillatory activity after applying to 2 different models of acute stress. In Experiment 1 Local Field Potentials (LFP) from the infralimbic division of the medial prefrontal cortex (IL), the basolateral division of the amygdala and the dorsal hippocampus, were recorded after the injection of corticotropin releasing hormone (CRH) in the dorsal raphe nucleus (DR). In Experiment 2, we analysed the effects of the electrical activation of the central nucleus of the amygdala (CeA) over the oscillatory dynamics of the IL. In addition, in Experiment 3 the effects of high-frequency electrical stimulation (DBS) targeting the nucleus accumbens core in the oscillatory activity of the infralimbic cortex were examined. Injection of CRH in the DR induced a general activation of the amygdala and the hippocampus, so a significant increment in theta waves power, as well as theta LFP coherence between these structures, was observed. Electrical activation of the CeA caused a delayed but significant change in IL, with prominent slow waves accompanied by an increase in theta activity, coupled with faster oscillations, including gamma and spindles. Interestingly, DBS of nucleus accumbens core generated a similar but not identical slow wave in the IL since spindles were not detected. These results are discussed in terms of processing of the stress response and

P Udaondo1,3, S Garcia-Delpech1,2, D Salom1,2, M Garcia-Pous1, M Diaz-Llopis1,21Department of Ophthalmology, Nuevo Hospital Universitario y Politecnico La Fe, Valencia, Spain; 2Faculty of Medicine, Universitat de València, Valencia, Spain; 3Universidad Cardenal Herrera CEU, Valencia, SpainAbstract: Q Fever is a zoonosis caused by Coxiella burnetii. Ocular manifestations are rare in this infection. We describe the case of a man complaining of an intense retro-orbital headache, fever, arthralgia, and bilateral loss of vision, who showed an anterior uveitis accompanied by exudative bilateral inferior retinal detachment and optic disk edema. At the beginning, a Vogt–Koyanagi–Harada (VKH) syndrome was suspected, but the patient was diagnosed with Q fever and treatment with doxycycline was initiated, with complete resolution after 2 weeks. We wondered if Q fever could unleash VKH syndrome or simulate a VKH syndrome by a similar immunological process.Keywords: Q fever, Vogt–Koyanagi–Harada syndrome, panuveitis, exudative retinal detachment