Pre-training to find a hidden platform in the Morris water maze can compensate for a deficit to find a cued platform in a rat model of Parkinson's disease

The bilateral intranigral infusion of 1 micromol 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in adult male Wistar rats caused a specific and partial loss of substantia nigra pars compacta (SNc) dopamine neurons, a partial depletion of striatal dopamine, and a deficit to learn the intra-maze cued version of the Morris water maze. Pre-training the SNc rats in the spatial version of the water maze or simply maintaining the animals on the water maze platform reversed this deficit. This improvement was even observed when the order of the extra-maze cues presented to the rats during pre-training of the spatial version was changed during training of the intra-maze cued version. However, this deficit was not reversed either by maintaining the animals on the platform if the spatial cues were surrounded and covered with a curtain or by swimming sessions in the maze without the escape platform and the curtain. These findings suggest that none of the following elements alone, learned during the spatial task pre-training, could help SNc rats learn the intra-maze cued task: improvement of swimming skills or knowledge of the existence of the escape platform; distance between the platform and the border of the pool; location of a particular extra-maze cue; relations among extra-maze cues. However, the simultaneous presence of the escape platform and extra-maze cues (irrespective of their relational configuration) during the pre-training sessions proved to be necessary for this improving effect to occur.     

Excuses,justifications, and the just war tradition: are there good reasons to kill the Naked Soldier?

In war there is a phenomenon known as the Naked Soldier problem (NS). A combatant discovers a vulnerable enemy combatant who is unable to defend himself and usually unaware of the combatant’s presence. This enemy combatant is not presently engaged in fighting and not threatening the lives of others. While killing the NS is legally permissible, the question I address in this essay is whether or not there can be a moral justification for doing so. I think such a moral justification is lacking, and there are only excuses for killing the NS. In this essay, I distinguish between a justification and an excuse and then I examine four traditional reasons given for the acceptability of killing in war to see if any of them are (a) justifications for killing in war in general and (b) justifications for killing the Naked Soldier, specifically.     

Repetitive transcranial magnetic stimulation improves depersonalization: a case report

Depersonalization disorder is a poorly understood and treatment-resistant condition. This report describes a patient with depersonalization disorder who underwent six sessions of repetitive transcranial magnetic stimulation on the left dorsolateral prefrontal cortex. Repetitive transcranial magnetic stimulation produced a 28% reduction on depersonalization scores.     

Amnesic effect of GMP depends on its conversion to guanosine

Extracellular guanine-based purines, namely the nucleotides GTP, GDP, GMP and the nucleoside guanosine, exert important neuroprotective and neuromodulator roles in the central nervous system, which may be related to inhibition of the glutamatergic neurotransmission activity. In this study, we investigated GMP effects on mice inhibitory avoidance performance and the dependence on its conversion to guanosine for such effect, by using the ecto-5'-nucleotidase specific inhibitor AOPCP. We also investigated if this conversion occurs in the central nervous system or peripherally, and if guanosine and GMP affect nociception by the tail-flick test. I.p. GMP or guanosine (7.5 mg/kg) or i.c.v. GMP (480 nmol) pretraining administration was amnesic for the inhibitory avoidance task. I.c.v. AOPCP (1 nmol) administration completely reversed the amnesic effect of i.c.v. GMP, but not of i.p. GMP, indicating that peripheral conversion of GMP to guanosine is probably relevant to this effect. AOPCP alone did not interfere with the performance. Furthermore, tail-flick measurement was unaffected by i.p. GMP and guanosine, suggesting that the amnesic effect of both purines was not due to some antinociceptive effect against the footshock used in the task. All these data together, in accordance to those previously observed in studies involving glutamate uptake and seizures reinforce the idea that guanosine is the specific extracellular guanine-based purines effector and indicate that its conversion occurs not only in the central nervous system but also peripherally.     

Idiopathic physical symptoms: a common manifestation of psychiatric disorders in primary care

Worldwide, patients with common mental disorders, such as depression and anxiety, have a tendency to present first to primary care exhibiting idiopathic physical symptoms. Typically, these symptoms consist of pain and other physical complaints that remain medically unexplained. While in the past, traditional psychopathology emphasized the relevance of somatic presentations for disorders, such as depression, in the last few decades, the "somatic component" has been neglected in the assessment and treatment of psychiatric patients. Medical specialties have come up with a variety of "fashionable" labels to characterize these patients and the new psychiatric nomenclatures, such as the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, attempt to classify these patients into a separate "somatoform disorders" category. These efforts fall short, and revisionists are asking altogether for the elimination of "somatoform disorders" from future nomenclatures. This review emphasizes the importance of idiopathic physical symptoms to the clinical phenomenology of many psychiatric disorders, offers suggestions to the diagnostic conundrum, and provides some hints for the proper assessment and management of patients with these common syndromes.     

Rapid resumption of interrupted visual search. New insights on the interaction between vision and memory

A modified visual search task demonstrates that humans are very good at resuming a search after it has been momentarily interrupted. This is shown by exceptionally rapid response time to a display that reappears after a brief interruption, even when an entirely different visual display is seen during the interruption and two different visual searches are performed simultaneously. This rapid resumption depends on the stability of the visual scene and is not due to display or response anticipations. These results are consistent with the existence of an iterative hypothesis-testing mechanism that compares information stored in short-term memory (the perceptual hypothesis) with information about the display (the sensory pattern). In this view, rapid resumption occurs because a hypothesis based on a previous glance of the scene can be tested very rapidly in a subsequent glance, given that the initial hypothesis-generation step has already been performed.     

On the role of object representations in substitution masking

Three experiments were conducted to investigate the role of object representations in object substitution masking (OSM). OSM occurs when a very sparse mask is presented simultaneously with a target stimulus and the target offsets first, leaving the mask to linger in the display for some time. Results confirm earlier claims that there is an isolatable object-level component to OSM and indicate that a target can be protected from OSM if, prior to offsetting, it can be represented as a distinct object from the mask. When the mask was presented as sliding past the target (Experiment 1), as jiggling independently of the target (Experiment 2), or in a different color from the target (Experiment 3), OSM was reduced or eliminated. This suggests that OSM reflects basic updating processes that allow the perception of continuity of object identity over change.     

Review of the Book Millennium Development Goals (MDGs) in Retrospect. Africa´s Development Beyond 2015

Applied Research in Quality of Life -