Targeted memory reactivation of face-name learning depends on ample and undisturbed slow-wave sleep

Face memory, including the ability to recall a person’s name, is of major importance in social contexts. Like many other memory functions, it may rely on sleep. We investigated whether targeted memory reactivation during sleep could improve associative and perceptual aspects of face memory. Participants studied 80 face-name pairs, and then a subset of spoken names with associated background music was presented unobtrusively during a daytime nap. This manipulation preferentially improved name recall and face recognition for those reactivated face-name pairs, as modulated by two factors related to sleep quality; memory benefits were positively correlated with the duration of stage N3 sleep (slow-wave sleep) and negatively correlated with measures of sleep disruption. We conclude that (a) reactivation of specific face-name memories during sleep can strengthen these associations and the constituent memories, and that (b) the effectiveness of this reactivation depends on uninterrupted N3 sleep.

Minocycline improves learning and memory functions in ischemic stroke rats via reduction of cerebral ischemia-induced neuroinflammation and apoptosis

Purpose: To study the effect minocycline on learning and memory functions in ischemic stroke rats, and the underlying mechanism. Methods: 60 adult male SD rats were randomly divided into control group, ischemic brain damage (6 and 24 h MACO) groups; and 6 and 24 h minocycline groups, with 12 rats in each group. The volume of cerebral infarction, neuronal cell apoptosis, NF-κB protein expression, learning and memory ability, and the number of Iba-1+CD206-positive cells, and CD206/CD68 mRNA expressions in sham group, 6 h MACO group and 6 h minocycline group were determined and compared. Results: The number of iba-1 +CD206-positive cells, expression level of CD206 mRNA, frequency of platform crossing, and percentage of third quadrant route in 6 h minocycline group were significantly higher than the corresponding values in 6 h MACO group. However, the cerebral infarction volume, number of Nini-positive cells, and the NF- B protein expression levels were markedly reduced, relative to corresponding values in 6 h MACO rats. The number of iba-1+CD206-positive cells was significantly lower in 6 h MACO rats than in sham rats, while the expression level of CD68 mRNA was significantly higher (p < 0.05). The number of TUNEL-positive cells in 6 and 24 h minocycline groups were markedly lower than that in 6 h MACO group (p < 0.05). Conclusion: Minocycline improves learning and memory of ischemic stroke rats by relieving the neuroinflammation induced by cerebral ischemia and cell apoptosis. Thus, the compound can be further developed for management learning and memory deficits in stroke patients.

Hippocampal Sclerosis in Pilocarpine Epilepsy: Survival of Peptide-Containing Neurons and Learning and Memory Disturbances in the Adult NMRI Strain Mouse

The present experiments reveal the alterations of the hippocampal neuronal populations in chronic epilepsy. The mice were injected with a single dose of pilocarpine. They had status epilepticus and spontaneously recurrent motor seizures. Three months after pilocarpine treatment, the animals were investigated with the Barnes maze to determine their learning and memory capabilities. Their hippocampi were analyzed 2 weeks later (at 3.5 months) with standard immunohistochemical methods and cell counting. Every animal displayed hippocampal sclerosis. The neuronal loss was evaluated with neuronal-N immunostaining, and the activation of the microglia was measured with Iba1 immunohistochemistry. The neuropeptide Y, parvalbumin, and calretinin immunoreactive structures were qualitatively and quantitatively analyzed in the hippocampal formation. The results were compared statistically to the results of the control mice. We detected neuronal loss and strongly activated microglia populations. Neuropeptide Y was significantly upregulated in the sprouting axons. The number of parvalbumin- and calretinin-containing interneurons decreased significantly in the Ammon’s horn and dentate gyrus. The epileptic animals displayed significantly worse learning and memory functions. We concluded that degeneration of the principal neurons, a numerical decrease of PV-containing GABAergic neurons, and strong peptidergic axonal sprouting were responsible for the loss of the hippocampal learning and memory functions.

Evaluation of Memory Complaints in People Living with HIV in Iran

Background: Several studies have reported that many people living with HIV (PLHIV) complain of memory impairments. Objectives: This study aimed to investigate these complaints both subjectively and objectively. Patients and Methods: For this purpose, 50 PLHIV and 50 of their companions as the control group were selected by the convenience sampling method in Shiraz, Iran, and completed Ray's auditory-verbal learning test and the Patient’s Assessment of Own Functioning Inventory (PAOFI). Data were analyzed using a t-test in SPSS. Results: Our findings showed a significant difference between PLHIV and the control group in terms of subjective memory complaints and objective memory functions. Conclusions: The overall result of the study showed that PLHIV reported more subjective memory complaints and poorer objective memory functions than the control group, regardless of the stage of the disease.

The Mechanisms of Cucurbitacin E as a Neuroprotective and Memory-Enhancing Agent in a Cerebral Hypoperfusion Rat Model: Attenuation of Oxidative Stress, Inflammation, and Excitotoxicity

Impaired cerebral hemodynamic autoregulation, vasoconstriction, and cardiovascular and metabolic dysfunctions cause cerebral hypoperfusion (CH) that triggers pro-oxidative and inflammatory events. The sequences linked to ion-channelopathies and calcium and glutamatergic excitotoxicity mechanisms resulting in widespread brain damage and neurobehavioral deficits, including memory, neurological, and sensorimotor functions. The vasodilatory, anti-inflammatory, and antioxidant activities of cucurbitacin E (CuE) can alleviate CH-induced neurobehavioral impairments. In the present study, the neuroprotective effects of CuE were explored in a rat model of CH. Wistar rats were subjected to permanent bilateral common carotid artery occlusion to induce CH on day 1 and administered CuE (0.25, 0.5 mg/kg) and/or Bay-K8644 (calcium agonist, 0.5 mg/kg) for 28 days. CH caused impairment of neurological, sensorimotor, and memory functions that were ameliorated by CuE. CuE attenuated CH-triggered lipid peroxidation, 8-hydroxy-2′-deoxyguanosine, protein carbonyls, tumor necrosis factor-α, nuclear factor-kappaB, myeloperoxidase activity, inducible nitric oxide synthase, and matrix metalloproteinase-9 levels in brain resulting in a decrease in cell death biomarkers (lactate dehydrogenase and caspase-3). CuE decreased acetylcholinesterase activity, glutamate, and increased γ-aminobutyric acid levels in the brain. An increase in brain antioxidants was observed in CuE-treated rats subjected to CH. CuE has the potential to alleviate pathogenesis of CH and protect neurological, sensorimotor, and memory functions against CH.

TRADUCTION FRANÇAISE DE L’ECHELLE THINKING ABOUT LIFE EXPERIENCE (TALE) - Mesure des fonctions de la mémoire autobiographique

Résumé :Le présent article propose la traduction en langue française d’une échelle d’investigation des fonctions de la mémoire autobiographique, disponible en langue anglaise, et que ses concepteurs ont intitulé TALE – Thinking About Life Experience. Ne disposant pas de version française de ce questionnaire, nous avons donc procédé à une traduction selon une méthode de rétro-traduction (back-translation).Nous proposons la divulgation de cette traduction française ainsi que la présentation de résultats issus de l’analyse statistique sur un échantillon de participants français (N=126).Mots-clés : Mémoire autobiographique, Fonction, Échelle, FrançaisFRENCH TRANSLATION OF THE THINKING ABOUT LIFE EXPERIENCE SCALE (TALE)Autobiographical memory functions assessmentAbstract :This article proposes a French translation of an investigation scale of the autobiographical memory functions, available in English, entitled TALE - Thinking About Life Experience. Since we did not have a French version of this questionnaire, we therefore carried out a translation using a back-translation method.We propose the disclosure of this French translation as well as the presentation of results from the statistical analysis on a sample of French participants (N = 126).Keywords : Autobiographical memory, Function, Scale, French

The search for statistical patterns of pathological activity in human EEG signals in focal epilepsy

Modern data science faces a lot of challenges, one of which is the search for diagnostic criteria for neurological diseases. New methods of statistical analysis are actively applied in the field of biophysics to solve this issue. In this paper we apply the Memory Functions Formalism to analyze electroencephalogram signal recordings in the sleeping state of 8 healthy subjects and 19 patients with nocturnal lobe epilepsy. We observe the considerable difference of statistical memory effects and fractal properties at the pathology in comparison with the control group. Furthermore, we reveal significant alterations in brain rhythms at power spectra of statistical memory functions for two groups of subjects. As a result, we show that the application of the statistical analysis methodology of bioelectrical brain cortex activity recordings, after appropriate verification, can be useful in the search for diagnostic criteria of nocturnal frontal lobe epilepsy.