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Abstract: Background: Studies suggest that the dorsolateral prefrontal cortex (DLPFC) participates in neural circuitry that is dysregulated in Panic Disorder (PD) and Major Depressive Disorder (MDD). We tested whether low-frequency repetitive Transcranial Magnetic Stimulation (rTMS) could normalize the overactivity of right frontal regions and thereby improve symptoms. Methods: Six patients with PD and comorbid MDD were treated with daily active 1-Hz rTMS to the right DLPFC for 2 weeks in this open-label trial. Results: Clinical improvements were apparent as early as the first week of treatment. After the second week, 5/6 of patients showed improvements in panic and anxiety, and 4/6 showed a decrease in depression, with sustained improvement at 6 months of follow-up. Right hemisphere resting motor threshold increased significantly after rTMS. Limitations: Limitations of this study are the open design and the small sample size. Conclusions: Slow rTMS to the right DLPFC resulted in significant clinical improvement and reduction of ipsilateral motor cortex excitability. Replications in larger sample will help to clarify the relevance of this preliminary data and to define the potential role of right DLPFC rTMS in panic with major depression. [Copyright &y& Elsevier]

Abstract: In this paper we present an off-line Kalman filter approach to remove transcranial magnetic stimulation (TMS)-induced artifacts from electroencephalographic (EEG) recordings. Two dynamic models describing EEG and TMS signals generation are identified from data and the Kalman filter is applied to the linear system arising from their combination. The keystone of the approach is the use of time-varying covariance matrices suitably tuned on the physical parameters of the problem that allow to model the nonstationary components of the EEG–TMS signal. This guarantees an efficient deletion of TMS-induced artifacts while preserving the integrity of EEG signals around TMS impulses. Experimental results show that the Kalman filter is more effective than stationary filters (Wiener filter) for the problem under investigation. [Copyright &y& Elsevier]

Mutations in the gene Leucine-Rich Repeat Kinase 2 ( LRRK2) have been identified in both dominant and sporadic cases affected by Parkinson's disease (PD). The LRRK2 G2019S mutation (c.6055G>A) is the most frequent substitution in Caucasians, accounting for approximately 5–6% of familial and 0.5–2.0% of apparently sporadic PD cases. We investigated the frequency of the LRRK2 G2019S mutation in 98 unrelated Italian PD patients, including 12 probands belonging to families compatible with autosomal dominant inheritance (12%) and 86 sporadic cases (88%). We detected the G2019S mutation in one sporadic female patient (1.2%). These results confirm that the G2019S mutation is a relevant cause of sporadic PD cases in the Italian population and stress the importance of performing this genetic test, which has important implications for genetic counselling. [ABSTRACT FROM AUTHOR]

Abstract: Recent neuroimaging studies of long-term episodic memory have suggested that left prefrontal cortex predominates in encoding condition, whereas right prefrontal cortex predominates in retrieval condition (hemispheric encoding and retrieval asymmetry, HERA model). The present electroencephalographic (EEG) study investigated the functional coupling of fronto-parietal regions during long-term memorization of visuo-spatial contents (i.e. landscapes, interiors of apartments), to test the predictions of the HERA model. Global fronto-parietal coupling was estimated by spectral coherence, whereas the “direction” of the fronto-parietal information flow was estimated by directed transfer function (DTF). The EEG rhythms of interest were theta (4–7Hz), alpha (8–13Hz), beta (14–30Hz), and gamma (30–45Hz). Statistically significant coherence in line with the HERA model was obtained at the gamma band. Namely, the fronto-parietal gamma coherence prevailed in the left hemisphere during the encoding condition and in the right hemisphere during the retrieval condition. The DTF estimates of the gamma band showed a dominant parietal-to-frontal directional flow in the right hemisphere during the encoding condition and in the left hemisphere during the retrieval condition (i.e. hemisphere-condition combination not involved by the HERA model). In contrast, a balanced bidirectional flow of the fronto-parietal coupling was observed in the left hemisphere during the encoding condition and in the right hemisphere during the retrieval condition (i.e. hemisphere-condition combination involved by the HERA model). In conclusion, the present encoding-retrieval conditions induced maximal fronto-parietal gamma coupling with bidirectional information flow in the hemisphere-condition combination predicted by the HERA model. [Copyright &y& Elsevier]

Unilateral movements are enabled through a distributed network of motor cortical areas but the relative contribution from the parts of this network is largely unknown. Failure of this network potentially results in mirror activation of the primary motor cortex (M1) ipsilateral to the intended movement. Here we tested the role of the right dorsal premotor cortex (dPMC) in 11 healthy subjects by disrupting its activity with 20 Hz repetitive transcranial magnetic stimulation (rTMS) whilst the subjects exerted a unilateral contraction of the left first dorsal interosseous (FDI). We found that disruption of right dPMC enhanced mirror activation of the ipsilateral left M1, as probed by motor evoked potential (MEP) amplitude to the right FDI. This was not the case with sham rTMS, when rTMS was directed to the right M1, or with rTMS of the right dPMC but without contraction of the left FDI. Findings suggest that activity in the dPMC contributes to the suppression of mirror movements during intended unilateral movements. [Copyright &y& Elsevier]

Neuroimaging cognitive study of aging requires simple tasks ensuring a high rate of correct performances even in stressful neurophysiological settings. Here two simple delayed choice reaction time tasks were used to unveil event-related desynchronization (ERD) of theta (4–6 Hz) and alpha (6–12 Hz) electroencephalographic rhythms across normal aging. In the first condition, a cue stimulus (one bit) was memorized along a brief delay period (3.5–5.5 s). The explicit demand was visuo-spatial, but the retention could be also based on phonological and somatomotor coding. In the second condition, the cue stimulus remained available along the delay period. Correct performances were higher than 95% in both groups and tasks, although they were significantly better in young than elderly subjects (P<0.03). During the delay period, theta and alpha ERD accompanying correct responses were recognized in the two groups, the alpha ERD being stronger and prolonged during the memory than non-memory task. On the other hand, the fronto-parietal theta and parietal alpha ERD were stronger in young than elderly subjects during both tasks. Notably, the frontal alpha ERD was negligible in elderly subjects. In conclusion, the present simple tasks unveiled in elderly compared to young subjects (i) a weaker involvement of (para)hippocampal-cortical circuits as revealed by theta ERD and (ii) a weaker involvement of “executive” thalamo-cortical circuits as revealed by frontal alpha ERD. These effects might worsen behavioral performances to the simple cognitive tasks with age. The present protocol is promising for the neuroimaging study of pathological aging. [Copyright &y& Elsevier]

In this electroencephalographic study, the authors modeled the functional connectivity between frontal and parietal areas during short-term memory (STM) processes by spectral coherence analysis and the directed transfer function, that is, for the estimation of coherence "direction." A no-STM task was used as a reference. STM was characterized by an increased frontoparietal electroencephalograph coherence at high frequencies (beta and gamma, 14-45 Hz). In the control task, parietal-to-frontal flow prevailed at those frequencies. However, the STM task showed a bidirectional frontoparietal flow at the gamma band. In conclusion, frontoparietal connectivity would optimize "representational" memory during STM. In this context, the frontal areas would increase their influence on parietal areas for memory retention. [ABSTRACT FROM AUTHOR]

Many recent neuroimaging studies of episodic memory have indicated an asymmetry in prefrontal involvement, with the left prefrontal cortex more involved than the right in encoding, the right more than the left in retrieval (hemispheric encoding and retrieval asymmetry, or HERA model). In this electroencephalographic (EEG) high-resolution study, we studied brain rhythmicity during a visual episodic memory (recognition) task. The theta (4–6 Hz), alpha (6–12 Hz) and gamma (28–48 Hz) oscillations were investigated during a visuospatial long-term episodic memory task including an encoding (ENC) and retrieval (RET) phases. During the ENC phase, 25 figures representing interiors of buildings (“indoor”) were randomly intermingled with 25 figures representing landscapes (“landscapes”). Subject''s response was given at left (“indoor”) or right (“landscapes”) mouse button. During the RET phase (1 h later), 25 figures representing previously presented “indoor” pictures (“tests”) were randomly intermingled with 25 figures representing novel “indoor” (“distractors”). Again, a mouse response was required. Theta and alpha EEG results showed no change of frontal rhythmicity. In contrast, the HERA prediction of asymmetry was fitted only by EEG gamma responses, but only in the posterior parietal areas. The ENC phase was associated with gamma EEG oscillations over left parietal cortex. Afterward, the RET phase was associated with gamma EEG oscillations predominantly over right parietal cortex. The predicted HERA asymmetry was thus observed in an unexpected location. This discrepancy may be due to the differential sensitivity of neuroimaging methods to selected components of cognitive processing. The strict relation between gamma response and perception suggests that retrieval processes of long-term memory deeply impinged upon sensory representation of the stored material. [Copyright &y& Elsevier]

Objective: We investigated whether a very simple short-term memory (STM) demand induces a visible change of EEG rhythms over the two hemispheres.Methods: High-resolution EEG was obtained in young adults during two delayed choice reaction time tasks. In the STM condition, a simple cue stimulus (one bit) was memorized along a brief delay period (3.5–5.5 s). The task was visuo-spatial in nature.Results: In the control (NSTM) condition, the cue stimulus remained available along the delay period. Compared to the control condition, the theta power (4–6 Hz) decreased in left frontal and bilateral parietal areas (delay period). Furthermore, low alpha power (6–8 Hz) decreased in bilateral frontal and left parietal areas, while high alpha power (10–12 Hz) decreased in the left fronto-parietal areas.Conclusions: The decrease of the alpha power is as an expression of the efficient information transfer within thalamo-cortical pathways. The significance of the study stands in the fact that even a very simple STM task (only one bit to be memorized) revealed changes in fronto-parietal theta and alpha rhythms. [Copyright &y& Elsevier]

Episodic Memory (EM) allows us to revive a past event through mental time-travel. The neural correlates of memories recollection have been identified in hippocampal regions and multiple neocortical areas, but few neuroimaging studies have used an ecological task such as a free recall of a structured story. Using an ecological fMRI-free recall (FR) task, we aimed to investigate the relevant recruitment of the brain networks associated with the story recollection process and its performance. Fourteen healthy participants listened to a brief story and were tested for Immediate-Recall (IR), a task that is widely used in a neuropsychological evaluation. Then, the subjects underwent an fMRI session, where they had to perform a free recall (FR) of the story subvocally. Finally, the participants were tested for Delayed-Recall (DR). IR and DR scores were significantly (r = 0.942; p < 0.001) correlated. FR enhanced the activity of the Language, the Left Executive Control, the Default Mode and the Precuneus brain networks, with the strongest BOLD signal localized in the left Angular Gyrus (AG) (p < 0.05; FWE-corrected). Furthermore, the story recall performance covaried with specific network activation patterns and the recruitment of the left anterior/posterior AG correlated, respectively, with higher/lower performance scores (p > 0.05). FR seems to be a promising task to investigate ecologically the neural correlates of EM. Moreover, the recruitment of the anterior AG might be a marker for an optimal functioning of the recall process. Preliminary outcomes lay the foundation for the investigation of the brain networks in the healthy and pathological elderly population during FR. [ABSTRACT FROM AUTHOR]

• Sleep deterioration is a common feature of normal and pathological aging. • Sleep abnormalities can trigger or exacerbate AD clinical symptoms and pathophysiology. • TMS can help investigating neural substrates of sleep and identify prognostic AD biomarkers. • tES can manipulate sleep to enhance memory consolidation and sleep efficiency. • Overall, brain stimulation could help improve sleep quality and protein clearance in healthy elderly and AD patients. As we age, sleep patterns undergo severe modifications of their micro and macrostructure, with an overall lighter and more fragmented sleep structure. In general, interventions targeting sleep represent an excellent opportunity not only to maintain life quality in the healthy aging population, but also to enhance cognitive performance and, when pathology arises, to potentially prevent/slow down conversion from e.g. Mild Cognitive Impairment (MCI) to Alzheimer's Disease (AD). Sleep abnormalities are, in fact, one of the earliest recognizable biomarkers of dementia, being also partially responsible for a cascade of cortical events that worsen dementia pathophysiology, including impaired clearance systems leading to build-up of extracellular amyloid-β (Aβ) peptide and intracellular hyperphosphorylated tau proteins. In this context, Noninvasive Brain Stimulation (NiBS) techniques, such as transcranial electrical stimulation (tES) and transcranial magnetic stimulation (TMS), may help investigate the neural substrates of sleep, identify sleep-related pathology biomarkers, and ultimately help patients and healthy elderly individuals to restore sleep quality and cognitive performance. However, brain stimulation applications during sleep have so far not been fully investigated in healthy elderly cohorts, nor tested in AD patients or other related dementias. The manuscript discusses the role of sleep in normal and pathological aging, reviewing available evidence of NiBS applications during both wakefulness and sleep in healthy elderly individuals as well as in MCI/AD patients. Rationale and details for potential future brain stimulation studies targeting sleep alterations in the aging brain are discussed, including enhancement of cognitive performance, overall quality of life as well as protein clearance. [ABSTRACT FROM AUTHOR]

The article presents information on the complications of duodenal levodopa or carbidopa gel infusion in the treatment of motor and non-motor symptoms in advanced Parkinson's disease. The technical issues like twisting, knotting or blockage of the tube and the complication due to buried bumper syndrome, local infection and dislocation of the tube in the stomach are also discussed.

The immersed boundary method is a mathematical framework for modeling fluid–structure interaction. This formulation describes the momentum, viscosity, and incompressibility of the fluid–structure system in Eulerian form, and it uses Lagrangian coordinates to describe the structural deformations, stresses, and resultant forces. Integral transforms with Dirac delta function kernels connect the Eulerian and Lagrangian frames. The fluid and the structure are both typically treated as incompressible materials. The discretization scheme can readily enforce incompressibility exactly for the Eulerian velocity field. Because of the regularization of the Dirac delta function kernel, however, the Lagrangian velocity field of the solid generally does not retain this property. To obtain an immersed method for incompressible hyperelastic structures that is robust under large structural deformations, we introduce a volumetric energy in the solid region that stabilizes the formulation and improves the accuracy of the numerical scheme. This formulation augments the discrete Eulerian Lagrange multiplier for the incompressibility constraint, thereby improving the original method's accuracy. This volumetric energy is incorporated by decomposing the strain energy into isochoric and dilatational components, as in standard solid mechanics formulations of nearly incompressible elasticity. We study the performance of the stabilized method using several quasi-static solid mechanics benchmarks, a dynamic fluid–structure interaction benchmark, and a detailed three-dimensional model of esophageal transport. The accuracy achieved by the stabilized immersed formulation is empirically demonstrated to be comparable to that of a stabilized finite element method for incompressible elasticity using similar numbers of structural degrees of freedom. • The hyperelastic immersed boundary method may not maintain solid incompressibility. • A stabilizing pressure in the solid region reduces spurious volume changes. • The method is inspired by volumetric penalization used in solid mechanics but not widely used in the IB method. • Excellent volume conservation is demonstrated via widely used elasticity benchmarks, a dynamic FSI test, and a model of esophageal transport. • The stabilization can be readily integrated in existing implementations. [ABSTRACT FROM AUTHOR]

Disorder of consciousness (DoC) refers to a group of clinical conditions that may emerge after brain injury, characterized by a varying decrease in the level of consciousness that can last from days to years. An understanding of its neural correlates is crucial for the conceptualization and application of effective therapeutic interventions. Here we propose a quantitative meta-analysis of the neural substrate of DoC emerging from functional magnetic resonance (fMRI) and positron emission tomography (PET) studies. We also map the relevant networks of resulting areas to highlight similarities with Resting State Networks (RSNs) and hypothesize potential therapeutic solutions leveraging network-targeted noninvasive brain stimulation. Available literature was reviewed and analyzed through the activation likelihood estimate (ALE) statistical framework to describe resting-state or task-dependent brain activation patterns in DoC patients. Results show that task-related activity is limited to temporal regions resembling the auditory cortex, whereas resting-state fMRI data reveal a diffuse decreased activation affecting two subgroups of cortical (angular gyrus, middle frontal gyrus) and subcortical (thalamus, cingulate cortex, caudate nucleus) regions. Clustering of their cortical functional connectivity projections identify two main altered functional networks, related to decreased activity of (i) the default mode and frontoparietal networks, as well as (ii) the anterior salience and visual/auditory networks. Based on the strength and topography of their connectivity profile, biophysical modeling of potential brain stimulation solutions suggests the first network as the most feasible target for tES, tDCS neuromodulation in DoC patients. [ABSTRACT FROM AUTHOR]

An amendment to this paper has been published and can be accessed via a link at the top of the paper. [ABSTRACT FROM AUTHOR]

We applied transcranial alternating current stimulation (tACS) to the primary motor cortex (M1) at different frequencies during an index–thumb pinch-grip observation task. To estimate changes in the corticospinal output, we used the size of motor evoked potentials (MEPs) obtained by transcranial magnetic stimulation (TMS) of M1 using an online MRI-guided simultaneous TMS-tACS approach. The results of the beta-tACS confirm a non-selective increase in corticospinal excitability in subjects at rest; an increase was observed for both of the tested hand muscles, the first dorsal interosseous (FDI) and the abductor digiti minimi (ADM). However, during action observation of the pinch-grip movement, the increase of corticospinal excitability was only observed for the prime mover FDI muscle and took place during alpha-tACS, while gamma-tACS affected both the FDI and control muscle (ADM) responses. These phenomena likely reflect the hypothesis that the mu and gamma rhythms specifically index the downstream modulation of primary sensorimotor areas by engaging mirror neuron activity. The current neuromodulation approach confirms that tACS can be used to induce neurophysiologically detectable state-dependent enhancement effects, even in complex motor-cognitive tasks. [ABSTRACT FROM AUTHOR]

The solution to a problem might manifest itself as a burst of unexpected, unpredictable clarity. Such Eureka! events, or Insight moments, are among the most fascinating mysteries of human cognition, whose neurophysiological substrate seems to include a role for oscillatory activity within the α and γ bands in the right parietal and temporal brain regions. We tested this hypothesis on thirty-one healthy participants using transcranial Alternating Current Stimulation (tACS) to externally amplify α (10 Hz) and γ (40 Hz) activity in the right parietal and temporal lobes, respectively. During γ-tACS over the right temporal lobe, we observed an increase in accuracy on a verbal insight task. Furthermore, electroencephalography (EEG) data revealed an increase in γ spectral power over bilateral temporal lobes after stimulation. Additionally, resting-state functional MRI data acquired before the stimulation session suggested a correlation between behavioral response to right temporal lobe tACS and functional connectivity of bilateral temporal lobes, in line with the bilateral increase in γ band revealed by EEG. Overall, results suggest the possibility of enhancing the probability of generating Eureka! moments in humans by means of frequency-specific noninvasive brain stimulation. [ABSTRACT FROM AUTHOR]

Introduction Only few studies have explored the pathophysiology of PSE; some Authors have suggested a defective visual inhibition as a contributing factor to photoparoxysmal response, pointing to an overactive visuomotor connectivity thus inducing abnormal motor responses. In order to investigate functional changes underlying photosensitivity, we studied the response of the visual cortex to low-frequency, inhibitory repetitive transcranial magnetic stimulation (rTMS) in drug-free patients with photosensitive seizures and healthy volunteers. Methods Visual evoked potentials (VEPs) triggered by grating stimuli of different luminance contrasts (K20%, K50% and K90%) were recorded in both hemispheres before and after transient functional inactivation of the occipital cortex of one side via low-frequency rTMS (0.5 Hz, at 120 % of resting motor threshold, for 20’). VEPs were recorded before (T0), immediately after (T1) and 45’ following the completion of rTMS (T2). The display was either centered on the vertical meridian (central stimulation) or positioned in the right hemifield (with its inner edge at a distance of 1 degree from the fixation point). Results Baseline amplitudes of the VEP components (N1 and P1) were enhanced in photosensitive patients. At T1, rTMS produced an inhibitory effect on VEPs amplitudes at all contrasts in the targeted side and a concurrent facilitation of responses in the contralateral hemisphere. Compared with PSE subjects, VEP amplitudes remained persistently dampened in the stimulated hemisphere of controls (Holm–Sidak post hoc method, p < 0.05). In the contralateral hemisphere, we found a clear enhancement of VEP amplitude in photosensitive subjects but not controls at T2 (Holm-Sidak test, p < 0.001). Conclusion The rapid recovery of excitability and the persistent transcallosal disinhibition following perturbation of cortical activity may play a role in the pathophysiology of photosensitive epilepsy. Beyond the stereotyped dichotomy between generalized and focal epilepsies, our data seem to indicate PSE as a “system disease”. [ABSTRACT FROM AUTHOR]

Objectives changes in interhemispheric connectivity have been recently studied in Huntington’s Disease (HD), although their significance and temporal relation with clinical features are still debated. We studied interhemispheric connectivity in healthy volunteers, early HD and in patients with idiopathic dystonia. Methods ipsilateral Silent Period (onset latency, iSPOL, and duration, iSPD) and Transcallosal Conduction Time (TCT) from the abductor pollicis brevis (APB) muscle were evaluated. In HD, we correlated TMS data with clinical (UHDRS-I, Disease Burden Index), genetic (CAG-length) and cognitive (UHDRS-II) scores. Results iSPD decreased in HD, paralleled by a significant lengthening of iSPOL and TCT ( p < 0.001) compared with healthy subjects. TMS changes significantly correlated with cognitive, motor scores and mutational load ( p < 0.01). TMS measures were more affected in the dominant than in non dominant hand ( p < 0.05). No significant change in TMS parameters was found in dystonia compared with healthy subjects (iSPOL: p = 0.32; iSPD: p = 0.39; TCT: p = 0.49). Discussion Our results could have implications for the disruption of both sensorimotor integration and voluntary motor control in HD. Before voluntary movements, interhemispheric interactions are responsible for the temporary inhibition of ipsilateral primary motor cortex (M1) and the increased excitability of contralateral one. Concurrently, especially during non-dominant hand movements, enhanced interhemispheric inhibition from the ipsilateral hemisphere suppresses superfluous activation arising from the contralateral cortex. These mutual interactions may be lost in symptomatic HD, thus contributing to hyperkinesias. Significance This is the first study using TMS to assess interhemispheric connectivity in hyperkinetic movement disorders, possibly leading to a better knowledge of disease mechanisms. [ABSTRACT FROM AUTHOR]

Objective To investigate functional changes underlying photosensitivity, we studied the response of the visual cortex to low-frequency, inhibitory repetitive transcranial magnetic stimulation (rTMS) in patients with photosensitive seizures and healthy volunteers. Methods Visual evoked potentials (VEPs) triggered by grating stimuli of different contrasts were recorded in both hemispheres before and after inactivation of the occipital cortex of one side via low-frequency rTMS (0.5 Hz, 120 % RMT, 20′). VEPs were recorded before (T0), immediately after (T1) and 45′ following rTMS (T2). The display was either centered on the vertical meridian (central stimulation) or positioned in the right hemifield (with its inner edge at a distance of 1 degree from the fixation point). Results Baseline amplitudes of the VEP components (N1 and P1) were enhanced in photosensitive patients. At T1, rTMS produced an inhibitory effect on VEPs amplitudes at all contrasts in the targeted side and a concurrent facilitation of responses in the contralateral hemisphere. Compared with PSE subjects, VEP amplitudes remained persistently dampened in the stimulated hemisphere of controls (Holm-Sidak post hoc method, p < 0.05). In the contralateral hemisphere, we found a clear enhancement of VEP amplitude in photosensitive subjects but not controls at T2 (Holm-Sidak test, p < 0.001). Conclusions The rapid recovery of excitability and the persistent transcallosal disinhibition following perturbation of cortical activity may play a role in the pathophysiology of photosensitive epilepsy. Significance beyond the stereotyped dichotomy between generalized and focal epilepsies, both sets of data seem to indicate PSE as a “system disease”. [ABSTRACT FROM AUTHOR]

Presents a letter to the editor of the "Journal of Neurology" about the clinical evidence of fluconazole-induced carbamazepine toxicity.

We aimed at investigating rapid effects of plasma cortisol elevations on the episodic memory phase of encoding or retrieval, and on the strength of the memory trace. Participants were asked either to select a word containing the letter "e" (shallow encoding task) or to judge if a word referred to a living entity (deep encoding task). We intravenously administered a bolus of 20 mg of cortisol either 5 min before encoding or 5 min before retrieval, in a between-subjects design. The study included only male participants tested in the late afternoon, and neutral words as stimuli. When cortisol administration occurred prior to retrieval, a main effect of group emerged. Recognition accuracy was higher for individuals who received cortisol compared to placebo. The higher discrimination accuracy for the cortisol group was significant for words encoded during deep but not shallow task. Cortisol administration before encoding did not affect subsequent retrieval performance (either for deep or shallow stimuli) despite a facilitatory trend. Because genomic mechanisms take some time to develop, such a mechanism cannot apply to our findings where the memory task was performed shortly after the enhancement of glucocorticoid levels. Therefore, glucocorticoids, through non-genomic fast effects, determine an enhancement in episodic memory if administered immediately prior to retrieval. This effect is more evident if the memory trace is laid down through deep encoding operations involving the recruitment of specific neural networks. [ABSTRACT FROM AUTHOR]