Search

Il disturbo narcisistico di personalità negli ultimi anni sta assumendo sempre più rilevanza al di là della diagnosi categoriale espressa dalle correnti classificazioni come il DSM-5. Infatti, mentre la diagnosi categoriale pone in primo piano la grandiosità, trattare il narcisismo come dimensione permette di tener conto della sua eterogeneità, identificando sottotipi che presentano diversi sintomi, gravità e impostazione del trattamento. In questo lavoro trattiamo il tema del narcisismo vulnerabile, caratterizzato da un'estrema sensibilità al giudizio, tendenza a sperimentare vergogna e colpa, e da comportamenti caratterizzati da inibizione ed evitamento. L'analisi di un caso di una persona affetta da narcisismo vulnerabile permetterà di descrivere come affrontare gli stati mentali di colpa e depressione, i comportamenti di evitamento sociale e di inibizione dei desideri. L'intervento terapeutico viene descritto utilizzando i trascritti di alcune sedute individuali in cui vengono applicate le procedure terapeutiche della terapia metacognitiva interpersonale (TMI).

In this chapter, we present the case of Enrico, which has all the characteristics of what we can call “complex cases.” The difficulties that the therapist faces in both diagnosis and treatment planning are illustrated. Enrico has a rather varied symptomatology that does not fit into a specific diagnostic framework, and giving multiple categorical diagnoses greatly complicates the work of the psychotherapist. Enrico’s case also allows us to illustrate the problems related to the current nosographic crisis that neither the DSM-5 nor the ICD-11 has completely resolved. However, we suggest that this crisis may possibly represent an opportunity and may open up new research perspectives.

This chapter describes the problems caused by impairments in two metacognitive subfunctions, differentiation and decentration, and suggests ways to improve them. Differentiation indicates the ability to recognize the representational nature of mental states, distinguishing clearly between the internal psychological content and external reality. In the presence of impaired differentiation, imagination takes on the properties of the real world. In this perspective, if patients are unable to recognize the subjectivity of their mental representations, they are also unable to maintain a critical distance from their representations. Decentration refers to the ability to assume other people’s perspectives and to make plausible hypotheses about their mental states. Specifically, it means being able to reflect on others’ intentions, thoughts, and desires, independent of one’s own personal point of view.

Study Objectives The aim of this study was to describe the spontaneous electroencephalographic (EEG) features of sleep in the human calcarine cortex, comparing them with the well-established pattern of the parietal cortex. Methods We analyzed presurgical intracerebral EEG activity in calcarine and parietal cortices during non-rapid eye movement (NREM) and rapid eye movement (REM) sleep in seven patients with drug-resistant focal epilepsy. The time course of the EEG spectral power and NREM vs REM differences was assessed. Sleep spindles were automatically detected. To assess homeostatic dynamics, we considered the first vs second half of the night ratio in the delta frequency range (0.5–4 Hz) and the rise rate of delta activity during the first sleep cycle. Results While the parietal area showed the classically described NREM and REM sleep hallmarks, the calcarine cortex exhibited a distinctive pattern characterized by: (1) the absence of sleep spindles; (2) a large similarity between EEG power spectra of NREM and REM; and (3) reduced signs of homeostatic dynamics, with a decreased delta ratio between the first and the second half of the night, a reduced rise rate of delta activity during the first NREM sleep cycle, and lack of correlation between these measures. Conclusions Besides describing for the first time the peculiar sleep EEG pattern in the human calcarine cortex, our findings provide evidence that different cortical areas may exhibit specific sleep EEG pattern, supporting the view of sleep as a local process and promoting the idea that the functional role of sleep EEG features should be considered at a regional level.

Objective Avoidant personality disorder (AvPD) is closely related to and partially overlaps with social phobia (SP). There is an ongoing debate as to whether AvPD and SP can be classified as separate and distinct disorders or whether these diagnoses rather reflect different degrees of severity of social anxiety. The hypothesis of this study is that in patients with AvPD and in those with AvPD and comorbid SP both interpersonal functioning and metacognitive abilities (the ability to understand mental states) are more severely impaired than they are in patients with SP only. We also hypothesise that the interpersonal and metacognitive functioning of these patients (both AvPD and AvPD + SP) is comparable to that of patients with other PD diagnoses. Methods To test this hypothesis, we compared four groups (22 patients with SP, 32 patients with AvPD, 43 patients with both AvPD and SP and 50 patients with other personality disorders without SP and AvPD criteria) on metacognitive abilities, interpersonal functioning and global symptomatic distress. Results Metacognitive ability showed significant variation among the four groups, with the lowest score observed in the AvPD group. As far as the interpersonal functioning is concerned, the lack of sociability was more severe in the AvPD group compared with the SP group. These differences were maintained even after controlling for global symptomatic distress. Conclusion Results are in line with the alternative model of PD, proposed in the DSM-5, as dysfunction of the self and relationships. They suggest that specific impairments in critical areas of self domains and interpersonal domains of personality functioning may serve as markers distinguishing AvPD from SP.

Background Grandiose narcissism has been associated with poor ability to understand one's own mental states and the mental states of others. In particular, two manifestations of Narcissistic Personality Disorder (NPD) can be explained by poor mindreading abilities: absence of symptomatic subjective distress and lack of empathy. Methods We conducted two studies to investigate the relationships between mindreading capacity, symptomatic subjective distress and narcissistic personality. In the first study (N = 246), we compared mindreading capacities and symptomatic distress in three outpatient samples: narcissistic patients (NPD); patients with other Personality Disorders (PD); patients without PD. In the second study (N = 1357), we explored the relationships between symptomatic distress, mindreading and specific NPD criteria. Results In the first study, the NPD patients showed poorer mindreading than the patients without PD and comparable to patients with other PDs. Symptomatic subjective distress in the narcissistic group was less severe than in the other PDs group and comparable to the group without PDs. However, no relationship emerged between mindreading and symptomatic subjective distress. In the second study, taking the clinical sample as a whole, symptomatic distress appeared negatively linked to grandiosity traits, while mindreading scores were negatively linked to empathy. Conclusions NPD showed specific mindreading impairments. However, mindreading capacity did not appear to be directly connected with subjective distress, but did appear to be connected with specific aspects of narcissistic pathology.

OBJECTIVES: The psychomotor vigilance task (PVT) is a widely used method for the assessment of vigilance after sleep deprivation (SDEP). However, the neural basis of PVT performance during SDEP has not been fully understood. In particular, no studies have investigated the possible relation between EEG topographical changes after sleep loss and PVT performance. The aim of the present study is to assess the EEG topographic correlates of PVT performance after SDEP. METHODS: During 40 h of SDEP, 16 healthy male subjects were evaluated in four sessions performed at the same time (11:00 a.m. and 11:00 p.m.) of the first and second day with: (a) subjective sleepiness recordings by means of the Karolinska Sleepiness Scale (KSS); (b) EEG recordings (5 min eyes-open condition); and (c) PVT. RESULTS: SDEP induced a slowing of PVT reaction times (RTs), higher level of subjective sleepiness and an increase of delta, theta, alpha and beta 1 EEG activity. Only slowest PVT RTs were influenced by circadian factors, with longer RTs in the morning. Both fastest PVT RTs and KSS scores were positively correlated with post-SDEP changes in EEG theta activity, mainly in centro-posterior areas, but not with other EEG frequencies. KSS scores and PVT measures were also positively correlated. CONCLUSIONS: These findings suggest that SDEP differently affects PVT variables, and that an increase in theta activity may be the principal EEG basis of the post-SDEP slowing of fastest PVT RTs. Similar neural mechanisms seem to underlie both performance deterioration to PVT and the increase of subjective sleepiness. Language: en

The hypothesis that sleep is instrumental in the process of memory consolidation is currently largely accepted. Hippocampal formation is involved in the acquisition of declarative memories and particularly of spatial memories. Nevertheless, although largely investigated in rodents, the relations between spatial memory and hippocampal EEG activity have been scarcely studied in humans. Aimed to evaluate the effects of spatial learning on human hippocampal sleep EEG activity, we recorded hippocampal Stereo-EEG (SEEG) in a group of refractory epilepsy patients undergoing presurgical clinical evaluation, after a training on a spatial navigation task. We observed that hippocampal high-delta (2-4 Hz range) activity increases during the first NREM episode after learning compared to the baseline night. Moreover, the amount of hippocampal NREM high-delta power was correlated with task performance at retest. The effect involved only the hippocampal EEG frequencies inasmuch no differences were observed at the neocortical electrodes and in the traditional polysomnographic measures. The present findings support the crucial role of hippocampal slow EEG frequencies during sleep in the memory consolidation processes. More generally, together with previous results, they suggest that slow frequency rhythms are a fundamental characteristic of human hippocampal EEG during both sleep and wakefulness, and are related to the consolidation of different types of memories.

We hypothesized that the brain shows specific and predictable patterns of spatial and temporal differences during sleep onset (SO) reflecting a temporal uncoupling of electrical activity between different cortical regions and a dissociated wakelike and sleeplike electrocortical activity in different cortical areas.We analyzed full-scalp electroencephalographic (EEG) recordings of 40 healthy subjects to investigate spatial and temporal changes of EEG activity across the wake-sleep transition. We quantified EEG sleep recordings by a fast Fourier transform (FFT) algorithm and by a better oscillation (BOSC) detection method to the EEG signals, which measured oscillatory activity within a signal containing a nonrhythmic portion.The most representative spatial change at SO is the frontalization of slow-wave activity (SWA), while the θ activity, which mostly shares a similar temporal and spatial pattern with SWA, exhibits a temporo-occipital diffusion. The time course of these oscillations confirms that the changes of the dominant waves coexist with topographic changes. The waking occipital prevalence of α oscillations is progressively replaced by an occipital prevalence of θ oscillations. On the other hand, more anterior areas show a wide synchronization pattern mainly expressed by slow waves just below 4 Hz and by spindle oscillations.The whole pattern of results confirms that the centrofrontal areas showed an earlier synchronization (i.e., they fall asleep first). This finding implies a coexistence of wakelike and sleeplike electrical activity during sleep in different cortical areas. It also implies that the process of progressive brain disconnection from the external world as we fall asleep does not necessarily affect primary and higher-order cortices at the same time.

The present electroencephalographic (EEG) study evaluated the hypothesis of a preferred directionality of communication flows between brain hemispheres across 24 h (i.e., during the whole daytime and nighttime), as an extension of a recent report showing changes in preferred directionality from pre-sleep wake to early sleep stages. Scalp EEGs were recorded in 10 normal volunteers during daytime wakefulness (eyes closed; first period: from 10:00 to 13:00 h; second period: from 14:00 to 18:00 h; third period: from 19:00 to 22:00 h) and nighttime sleep (four NREM-REM cycles). EEG rhythms of interest were delta (1-4 Hz), theta (5-7 Hz), alpha (8-11 Hz), sigma (12-15 Hz) and beta (16-28 Hz). The direction of the inter-hemispheric information flow was evaluated by computing the directed transfer function (DTF) from these EEG rhythms. Inter-hemispheric directional flows varied as a function of the state of consciousness (wake, NREM sleep, REM sleep) and in relation to different cerebral areas. During the daytime, alpha and beta rhythms conveyed inter-hemispheric signals with preferred Left-to-Right hemisphere direction in parietal and central areas, respectively. During the NREM sleep periods of nighttime, the direction of inter-hemispheric DTF information flows conveyed by central beta rhythms was again preponderant from Left-to-Right hemisphere in the stage 2, independent of cortical areas. No preferred direction emerged across the REM periods. These results support the hypothesis that specific directionality of communication flows between brain hemispheres is associated with wakefulness, NREM (particularly stage 2) and REM states during daytime and nighttime. They also reinforce the suggestive hypothesis of a relationship between inter-hemispheric directionality of EEG functional coupling and frequency of the EEG rhythms.

Although a large body of evidence indicates that sleep plays an important role in learning and memory processes, the actual existence of a sleep-dependent spatial memory consolidation has been not firmly established. Here, by using a computerized 3D virtual navigation tool, we were able to show that topographical orientation in humans largely benefits from sleep after learning, while 10 h of wakefulness during the daytime do not exert similar beneficial effects. In particular, navigation performance enhancement needs sleep in the first post-training night, and no further improvements were seen after a second night of sleep. On the other hand, sleep deprivation hinders any performance enhancement and exerts a proactive disruption of spatial memory consolidation, since recovery sleep do not revert its effects. Spatial memory performance does not benefit from the simple passage of time, and a period of wakefulness between learning and sleep does not seem to have the role of stabilizing memory traces. In conclusion, our results indicate that spatial performance improvement is observed only when learning is followed by a period of sleep, regardless of the retention interval length.

The ability to reflect on one's own states of mind and those of others (metacognition or mindreading) is strongly implicated in personality disorders (PDs). Metacognition involves different abilities, and there is evidence that specific abilities can be selectively impaired in different PDs. The purposes of this study were to compare metacognitive competence in avoidant PD (AvPD) with that in other PDs and to investigate whether there is a specific profile for AvPD. Sixty-three patients with AvPD and 224 patients with other PDs were assessed using the Metacognitive Assessment Interview. AvPD patients showed difficulties with two metacognitive functions: monitoring and decentration, even when the severity of psychopathology was controlled for. These results support the hypothesis of specific profiles of metacognitive dysfunction in different PDs and highlight a close link between impaired monitoring and decentration functions and the inhibited and withdrawn personality style typical of AvPD.

The capacity of understanding mental states is a complex function which involves several components. Single components can be selectively impaired in specific clinical populations. It has been suggested that impairments in mindreading are central for borderline personality disorder (BPD). However, empirical findings are inconsistent, and it is debatable whether BPD presents a specific profile of mindreading impairments. The aim of this study is to compare BPD and other PDs in mindreading. Seventy-two patients with BPD and 125 patients with other PD diagnoses were assessed using the Metacognition Assessment Interview. BPD showed difficulties in two mindreading functions, differentiation and integration, even when the severity of psychopathology was controlled. These results suggest a specific mindreading impairment in BPD and a strong relationship between these impairments and the severity of psychopathology.

The aim of the present study was to characterize the regional electroencephalographic substratum of the awakening process by means of a Hz-by-Hz EEG spectral power analysis. For this purpose, we recorded a group of 25 female subjects who slept for at least two consecutive nights in the laboratory. The post-sleep waking EEG was compared to the one recorded during the presleep wakefulness from four midline derivations (Fz-A1, Cz-A1, Pz-A1, Oz-A1). Results indicated that the first 10 min after awakening are characterized by an increase of EEG power in the low-frequency range (1-9 Hz) compared to the corresponding presleep waking period, and by a significant decrease of EEG power in the beta range (18-24 Hz). As regards topographic differences, the increase of EEG power upon awakening in the delta-theta range showed a parieto-occipital prevalence. Moreover, the occipital derivation showed a larger decrease of power in the beta range as compared to the other derivations. In conclusion, the EEG substratum of the sleep offset period is characterized by a pattern of increased EEG power in the delta-theta and low-alpha bands, and of decreased power in the beta range. This pattern could be considered as the spectral EEG signature of the sleep inertia phenomenon. The state of post-sleep EEG hypo-arousal does not subside in the first 10-min period after awakening considered in the present analysis. Finally, according to our results, the more posterior scalp locations show stronger EEG signs of sleep inertia, and could be the last ones to properly wake up.

We recorded the resting electroencephalogram of 20 healthy subjects in order to investigate the effect of electromagnetic field (EMF) exposure on EEG waking activity and its temporal development. The subjects were randomly assigned to two groups and exposed, in double-blind conditions, to a typical mobile phone signal (902.40 MHz, modulated at 217 Hz, with an average power of 0.25 W) before or during the EEG recording session. The results show that, under real exposure as compared to baseline and sham conditions, EEG spectral power was influenced in some bins of the alpha band. This effect was greater when the EMF was on during the EEG recording session than before it. The present data lend further support to the idea that pulsed high-frequency electromagnetic fields can affect normal brain functioning, also if no conclusions can be drawn about the possible health effects.

The coexistence of regionally dissociated brain activity patterns -with some brain areas being active while other already showing sleep signs- may occur throughout all vigilance states including the transition from wakefulness to sleep and may account for both physiological as well as pathological events. These dissociated electrophysiological states are often characterized by multi-domain cognitive and behavioral impairment such as amnesia for events immediately preceding sleep. By performing simultaneous intracerebral electroencephalographic recordings from hippocampal as well as from distributed neocortical sites in neurosurgical patients, we observed that sleep spindles consistently occurred in the hippocampus several minutes before sleep onset. In addition, hippocampal spindle detections consistently preceded neocortical events, with increasing delays along the cortical antero-posterior axis. Our results support the notion that wakefulness and sleep are not mutually exclusive states, but rather part of a continuum resulting from the complex interaction between diffuse neuromodulatory systems and intrinsic properties of the different thalamocortical modules. This interaction may account for the occurrence of dissociated activity across different brain structures characterizing both physiological and pathological conditions.

The hypothesis that sleep is instrumental in the process of memory consolidation is currently largely accepted. Hippocampal formation is involved in the acquisition of declarative memories and particularly of spatial memories. Nevertheless, although largely investigated in rodents, the relations between spatial memory and hippocampal EEG activity have been scarcely studied in humans. Aimed to evaluate the effects of spatial learning on human hippocampal sleep EEG activity, we recorded hippocampal Stereo-EEG (SEEG) in a group of refractory epilepsy patients undergoing presurgical clinical evaluation, after a training on a spatial navigation task. We observed that hippocampal high-delta (2-4 Hz range) activity increases during the first NREM episode after learning compared to the baseline night. Moreover, the amount of hippocampal NREM high-delta power was correlated with task performance at retest. The effect involved only the hippocampal EEG frequencies inasmuch no differences were observed at the neocortical electrodes and in the traditional polysomnographic measures. The present findings support the crucial role of hippocampal slow EEG frequencies during sleep in the memory consolidation processes. More generally, together with previous results, they suggest that slow frequency rhythms are a fundamental characteristic of human hippocampal EEG during both sleep and wakefulness, and are related to the consolidation of different types of memories.

Background: Changes of cortical excitability after sleep deprivation (SD) in humans have been investigated mostly in motor cortex, while there is little empirical evidence concerning somatosensory cortex, and its plastic changes across SD. Objective: To assess excitability of primary somatosensory cortex (S1) and EEG voltage topographical characteristics associated with somatosensory evoked potentials (SEPs) during SD. Methods: Across 41 h of SD, 16 healthy subjects participated in 4 experimental sessions (11.00 a.m. and 11.00 p.m. of the 1st and 2nd day) with: a) subjective sleepiness ratings; b) EEG recordings; c) SEPs recordings; d) behavioral vigilance responses. Results: A clear enhancement of cortical excitability after SD was indexed by: (a) an amplitude increase of different SEPs component in S1; (b) higher voltage in occipital (around 35–43 ms) and fronto-central areas (around 47–62 ms). Circadian fluctuations did not affect cortical excitability. Voltage changes in S1 were strongly related with post-SD fluctuations of subjective and behavioral sleepiness. Conclusions: Sleep may have a role in keeping cortical excitability at optimal (namely below potentially dangerous) levels for the human brain, rebalancing progressive changes in cortical responsiveness to incoming inputs occurred during time spent awake. On the other hand, higher level of cortical responsiveness after sleep loss may be one of the mechanisms accounting for post-SD alterations in vigilance and behavior.

Human sleep is considered a global phenomenon, orchestrated by central specialized neuronal networks modulating the whole-brain activity. However, recent studies point to a local regulation of sleep. Sleep disorders, such as sleepwalking, suggest that electroencephalographic (EEG) features of sleep and wakefulness might be simultaneously present in different cerebral regions. Recently, intracranial EEG recording techniques, mainly applied for the presurgical evaluation of drug-resistant epileptic patients, have provided new and interesting information on the activity of different cortical and subcortical structures during sleep in humans. In particular, it has been observed that the thalamus, during the transition between wake and sleep undergoes a deactivation process that precedes the one occurring within the cortex, with extensive cortical territories maintaining an activated pattern for several minutes after the thalamic deactivation. Very recent intracerebral EEG studies have also shown that human NREM sleep can be characterized by the coexistence of wake-like and sleep-like EEG patterns in different cortical areas. Moreover, unit-firing recordings in multiple brain regions of neurosurgical patients evidenced that most sleep slow waves and the underlying active and inactive neuronal states do occur locally. These findings add a new dimension to the concept of local sleep regulation and opens new perspectives in the interpretation of the substrates underlying behavioral states of vigilance. The implications for sleep medicine are also discussed.

Human sleep is considered a global phenomenon, orchestrated by central specialized neuronal networks modulating the whole-brain activity. However, recent studies point to a local regulation of sleep. Sleep disorders, such as sleepwalking, suggest that electroencephalographic (EEG) features of sleep and wakefulness might be simultaneously present in different cerebral regions. Recently, intracranial EEG recording techniques, mainly applied for the presurgical evaluation of drug-resistant epileptic patients, have provided new and interesting information on the activity of different cortical and subcortical structures during sleep in humans. In particular, it has been observed that the thalamus, during the transition between wake and sleep undergoes a deactivation process that precedes the one occurring within the cortex, with extensive cortical territories maintaining an activated pattern for several minutes after the thalamic deactivation. Very recent intracerebral EEG studies have also shown that human NREM sleep can be characterized by the coexistence of wake-like and sleep-like EEG patterns in different cortical areas. Moreover, unit-firing recordings in multiple brain regions of neurosurgical patients evidenced that most sleep slow waves and the underlying active and inactive neuronal states do occur locally. These findings add a new dimension to the concept of local sleep regulation and opens new perspectives in the interpretation of the substrates underlying behavioral states of vigilance. The implications for sleep medicine are also discussed.

Converging data that attribute a central role to sleep in memory consolidation have increased the interest to understand the characteristics of the hippocampal sleep and their relations with the processing of new information. Neural synchronization between different brain regions is thought to be implicated in long-term memory consolidation by facilitating neural communication and by promoting neural plasticity. However, the majority of studies have focused their interest on intra-hippocampal, rhinal-hippocampal or cortico-hippocampal synchronization, while inter-hemispheric synchronization has been so far neglected. To clarify the features of spontaneous human hippocampal activity and to investigate inter-hemispheric hippocampal synchronization across vigilance states, pre-sleep wakefulness and nighttime sleep were recorded from right and left homologous hippocampal loci using stereo-EEG techniques. Hence, quantitative and inter-hemispheric coherence analyses of hippocampal activity across sleep and waking states were carried out. The results showed the presence of delta activity in human hippocampal spontaneous EEG also during wakefulness. The activity in the delta range exhibited a peculiar bimodal distribution, namely a low frequency non-oscillatory activity (up to 2 Hz) synchronized between hemispheres mainly during wake and REM sleep, and a faster oscillatory rhythm (2-4 Hz). The latter was less synchronized between the hippocampi and seemed reminiscent of animal RSA (rhythmic slow activity). Notably, the low-delta activity showed high inter-hemispheric hippocampal coherence during REM sleep and, to a lesser extent, during wakefulness, paralleled by a (unexpected) decrease of coherence during NREM sleep. Therefore, low-delta hippocampal state-dependent synchronization starkly contrasts with neocortical behavior in the same frequency range. Further studies might shed light on the role of these low frequency rhythms in the encoding processes during wakefulness and in the consolidation processes during subsequent sleep.

The recent spread of intracranial electroencephalographic (EEG) recording techniques for presurgical evaluation of drug-resistant epileptic patients is providing new information on the activity of different brain structures during both wakefulness and sleep. The interest has been mainly focused on the medial temporal lobe, and in particular the hippocampal formation, whose peculiar local sleep features have been recently described, providing support to the idea that sleep is not a spatially global phenomenon. The study of the hippocampal sleep electrophysiology is particularly interesting because of its central role in the declarative memory formation. Recent data indicate that sleep contributes to memory formation. Therefore, it is relevant to understand whether specific patterns of activity taking place during sleep are related to memory consolidation processes. Fascinating similarities between different states of consciousness (wakefulness, REM sleep, non-REM sleep) in some electrophysiological mechanisms underlying cognitive processes have been reported. For instance, large-scale synchrony in gamma activity is important for waking memory and perception processes, and its changes during sleep may be the neurophysiological substrate of sleep-related deficits of declarative memory. Hippocampal activity seems to specifically support memory consolidation during sleep, through specific coordinated neurophysiological events (slow waves, spindles, ripples) that would facilitate the integration of new information into the pre-existing cortical networks. A few studies indeed provided direct evidence that rhinal ripples as well as slow hippocampal oscillations are correlated with memory consolidation in humans. More detailed electrophysiological investigations assessing the specific relations between different types of memory consolidation and hippocampal EEG features are in order. These studies will add an important piece of knowledge to the elucidation of the ultimate sleep function.

The aim of this study is to validate the Italian version of the Pittsburgh Sleep Quality Index (PSQI), comparing five different groups of individuals (healthy young and elderly, sleep apnoea syndrome patients, depressed patients, individuals with dementia) by both questionnaire scores and polysomnographic measures. Fifty individuals (10 for each group) participated in the study. Each of them filled in the PSQI and slept for two consecutive nights in the sleep laboratory. The PSQI showed an overall reliability coefficient (Cronbach’s α) of 0.835, indicating a high degree of internal consistency. The mean PSQI global score showed significant differences between groups, with an impaired overall quality of sleep in patients’ groups with respect to both the healthy groups. Results also indicated that the best cut-off score (differentiating “good” from “bad” sleepers) is 5. Pittsburgh Sleep Quality Index is a useful, valid and reliable tool for the assessment of sleep quality, with an overall efficiency comparable to the mother language version and differentiate “good” from “bad” sleepers. The Italian version of the questionnaire provides a good and reliable differentiation between normal and pathological groups, with higher scores reported by people characterized by impaired objectively evaluated sleep quality.

Sleep is traditionally considered a global process involving the whole brain. However, recent studies have shown that sleep depth is not evenly distributed within the brain. Sleep disorders, such as sleepwalking, also suggest that EEG features of sleep and wakefulness might be simultaneously present in different cerebral regions. In order to probe the coexistence of dissociated (wake-like and sleep-like) electrophysiological behaviors within the sleeping brain, we analyzed intracerebral electroencephalographic activity drawn from sleep recordings of five patients with pharmacoresistant focal epilepsy without sleep disturbances, who underwent pre-surgical intracerebral electroencephalographic investigation. We applied spectral and wavelet transform analysis techniques to electroencephalographic data recorded from scalp and intracerebral electrodes localized within the Motor cortex (Mc) and the dorso-lateral Prefrontal cortex (dlPFc). The Mc showed frequent Local Activations (lasting from 5 to more than 60 s) characterized by an abrupt interruption of the sleep electroencephalographic slow waves pattern and by the appearance of a wake-like electroencephalographic high frequency pattern (alpha and/or beta rhythm). Local activations in the Mc were paralleled by a deepening of sleep in other regions, as expressed by the concomitant increase of slow waves in the dlPFc and scalp electroencephalographic recordings. These results suggest that human sleep can be characterized by the coexistence of wake-like and sleep-like electroencephalographic patterns in different cortical areas, supporting the hypothesis that unusual phenomena, such as NREM parasomnias, could result from an imbalance of these two states.

Sleep inertia (SI) denotes a period of hypovigilance, confusion and impaired cognitive and behavioral performance that immediately follows awakening. Based on the observation that the reactivation of some cortical areas is faster than other upon awakening, here we examined regional differences between presleep and postsleep waking period. Moreover, we also compared rapid eye movements (REM) and stage 2 non-rapid eye movements (NREM) awakenings in a within-subject design. Presleep and postsleep waking electroencephalogram (EEG; 5 min with eyes-closed and 5 min with eyes-open) of 18 healthy subjects (12 males, mean age=23.8±2.3 years) were recorded from 19 derivations. Participants slept for two consecutive nights in the laboratory. In one night they were awakened from stage 2 NREM, while in the other from REM sleep. EEG power spectra were calculated across the following bands: delta (1-4 Hz), theta (5-7 Hz), alpha (8-12 Hz), beta-1 (13-16 Hz) and beta-2 (17-24 Hz). Moreover, a detailed hertz-by-hertz analysis has been repeated in the 2-4 Hz frequency range. Postsleep wakefulness, compared to presleep, is characterized by a generalized decrease of higher beta-1 and beta-2 EEG power over almost all scalp locations. A detailed analysis of topographical modifications in the low-frequency range showed that postsleep wakefulness is characterized by an increased delta activity in the posterior scalp locations, and by a concomitant frontal decrease compared to presleep. Moreover, it was found a prevalence of EEG power in the high frequency ranges (beta-1 and beta-2) upon awakening from stage 2 compared to REM awakenings over the left anterior derivations. Altogether these findings support the hypothesis that a generalized reduction in beta activity and increased delta activity in more posterior areas upon awakening may represent the EEG substratum of the sleep inertia phenomenon.

Under the assumption that dream recall is a peculiar form of declarative memory, we have hypothesized that (1) the encoding of dream contents during sleep should share some electrophysiological mechanisms with the encoding of episodic memories of the awake brain and (2) recalling a dream(s) after awakening from non-rapid eye movement (NREM) and rapid eye movement (REM) sleep should be associated with different brain oscillations. Here, we report that cortical brain oscillations of human sleep are predictive of successful dream recall. In particular, after morning awakening from REM sleep, a higher frontal 5–7 Hz (theta) activity was associated with successful dream recall. This finding mirrors the increase in frontal theta activity during successful encoding of episodic memories in wakefulness. Moreover, in keeping with the different EEG background, a different predictive relationship was found after awakening from stage 2 NREM sleep. Specifically, a lower 8–12 Hz (alpha) oscillatory activity of the right temporal area was associated with a successful dream recall. These findings provide the first evidence of univocal cortical electroencephalographic correlates of dream recall, suggesting that the neurophysiological mechanisms underlying the encoding and recall of episodic memories may remain the same across different states of consciousness.

Sleep deprivation (SD) negatively affects various cognitive performances, but surprisingly evidence about a specific impact of sleep loss on subjective evaluation of emotional stimuli remains sparse. In the present study, we assessed the effect of SD on the emotional rating of standardized visual stimuli selected from the International Affective Picture System. Forty university students were assigned to the sleep group (n=20), tested before and after one night of undisturbed sleep at home, or to the deprivation group, tested before and after one night of total SD. One-hundred and eighty pictures (90 test, 90 retest) were selected and categorized as pleasant, neutral and unpleasant. Participants were asked to judge their emotional reactions while viewing pictures by means of the Self-Assessment Manikin. Subjective mood ratings were also obtained by means of Visual Analog Scales. No significant effect of SD was observed on the evaluation of pleasant and unpleasant stimuli. On the contrary, SD subjects perceived the neutral pictures more negatively and showed an increase of negative mood and a decrease of subjective alertness compared to non-deprived subjects. Finally, an analysis of covariance on mean valence ratings of neutral pictures using negative mood as covariate confirmed the effect of SD. Our results indicate that sleep is involved in regulating emotional evaluation. The emotional labeling of neutral stimuli biased toward negative responses was not mediated by the increase of negative mood. This effect can be interpreted as an adaptive reaction supporting the "better safe than sorry" principle. It may also have applied implications for healthcare workers, military and law-enforcement personnel.

The study investigated the effect of one night of sleep deprivation on dream recall at morning awakening after recovery sleep. Forty healthy subjects were studied after adaptation (A) and baseline nights (B), and a recovery (R) night following 40 h of prolonged wakefulness. Parallel to the well-known recovery sleep changes (slow-wave sleep – SWS – rebound, decreased number of awakenings and of REM sleep amount), an almost complete abolition of dream recall was found, with an around 75% decrease with respect to the adaptation and baseline nights. The number of dreams recalled by those subjects with successful recall (REC) did not significantly differ between nights. Moreover, gender and sleep stage at awakening did not affect either the proportion of REC subjects or the number of dreams recalled by REC subjects during each night. Finally, the drastic impairment of dream recall after R night was associated to a larger increase of SWS and a shorter REM sleep duration. We suggest that dream recall could have been impaired during R night because: (i) the lower number of spontaneous awakenings over the night reduced the contents available in memory as possible cues for the retrieval of dream experiences at morning; (ii) mental experiences, having been elaborated during SWS more than in the other nights, were less dreamlike (i.e., perceptually vivid and bizarre) and, thus less accessible at morning recall than those elaborated during the nights with a higher proportion of REM sleep; (iii) dream contents, as a peculiar type of episodic information, were less consolidated because of the lower effectiveness of declarative memory during recovery sleep.

The present study investigated the presence of a cumulative effect of brief and repeated exposures to a GSM mobile phone (902.40 MHz, 217 Hz modulated; peak power of 2 W; average power of 0.25 W; SAR = 0.5 W/kg) on psychomotor functions. To this end, after each of 3 15-min exposures, both an acoustic simple reaction time task (SRTT) and a sequential finger tapping task (SFTT) were administered to 24 subjects. The present study was unable to detect the cumulative effects of brief and repeated EMF exposure on human psychomotor performance, although there was a non-statistical trend to shorter reaction times. In summary, these data show an absence of effects with these particular exposure conditions; however, possible cognitive effects induced by different signal characteristics cannot be excluded. Bioelectromagnetics 29:237–241, 2008. © 2007 Wiley-Liss, Inc.

Humans have an individual profile of the electroencephalographic power spectra at the 8 to 16 Hz frequency during non-rapid eye movement sleep that is stable over time and resistant to experimental perturbations. We tested the hypothesis that this electroencephalographic "fingerprint" is genetically determined, by recording 40 monozygotic and dizygotic twins during baseline and recovery sleep after prolonged wakefulness. We show a largely greater similarity within monozygotic than dizygotic pairs, resulting in a heritability estimate of 96%, not influenced by sleep need and intensity. If replicated, these results will establish the electroencephalographic profile during sleep as one of the most heritable traits of humans.

Recent evidence suggests that slow EEG rhythms are involved in post-learning plasticity. However, the relationships between memory consolidation and hippocampal EEG features remain unclear. Here, we assessed the effects of both procedural and declarative learning on qualitative and quantitative measures of sleep by recording stereo-EEG (SEEG) directly from the hippocampus and the neocortex in a group of epileptic patients undergoing pre-surgical evaluations. Following a baseline night, sleep was recorded after administration of a declarative (paired-associate word list learning task) and a procedural (sequential finger tapping) task. Patients were tested before going to bed (test) and after sleep in the following morning (retest). At retest, we found that patients recalled correctly more word pairs compared to the pre-sleep test (declarative task), and they were slightly faster in performing the motor task (procedural task). Standard polysomnography showed an increase in the amount of slow-wave sleep (SWS) only after procedural learning, paralleled by an increase of hippocampal SEEG power in the very low frequency range (VLF, 0.5-1 Hz) during the first NREM sleep cycle. Moreover, procedural performance enhancement and SEEG power increase in the hippocampal VLF were significantly correlated, indicating a link between procedural memory consolidation and slow hippocampal SEEG rhythms. These findings are consistent with the hypothesis of synaptic homeostasis occurring during sleep, suggesting that hippocampal slow oscillations are associated with local processes of post-learning synaptic downscaling.

Changes of cortical and corticospinal excitability as a function of sleep deprivation have been studied, using EEG power maps and several TMS measures in 33 normal subjects before and after a 40-h sleep deprivation (SD). The effects of SD were independently assessed by subjective and EEG measures of sleepiness, the latter being represented in terms of cortical maps for different frequency bands. Short intracortical facilitation (SICF) and inhibition (SICI) were measured by the paired-pulse TMS technique with different inter-stimulus intervals. Besides standardized motor threshold (MT), lower threshold (LT) and upper threshold (UT) were also determined. Subjective sleepiness severely increased as a consequence of SD, paralleled by a drastic decrease of alertness. EEG topography showed large increases in delta and theta activity, mainly evident at fronto-central areas. Standard MTs, as well as LTs and UTs, all increased as a consequence of SD. SICF also showed a significant increase as compared to pre-deprivation values, but only in females. The increase of theta activity was strongly associated in the left frontal and prefrontal cortex to a smaller decrease of corticospinal excitability, expressed by MTs, and a larger increase of intracortical facilitation, expressed by SICF. TMS and EEG measures converge in indicating that SD has severe effects on both cortical and corticospinal excitability, as shown respectively by the increases of slow-frequency EEG power and MTs. The SICF enhancement in females and the results of the combined topographical analysis of EEG and TMS changes are coherent with the hypothesis that cortical TMS-evoked responses are higher as a consequence of a longer wakefulness. However, the lack of an increase in cortical excitability after prolonged wakefulness in males suggests some caution in the generalization of these effects, that deserve further investigation.

Background There is compelling evidence indicating that sleep plays a crucial role in the consolidation of new declarative, hippocampus-dependent memories. Given the increasing interest in the spatiotemporal relationships between cortical and hippocampal activity during sleep, this study aimed to shed more light on the basic features of human sleep in the hippocampus. Methodology/Principal Findings We recorded intracerebral stereo-EEG directly from the hippocampus and neocortical sites in five epileptic patients undergoing presurgical evaluations. The time course of classical EEG frequency bands during the first three NREM-REM sleep cycles of the night was evaluated. We found that delta power shows, also in the hippocampus, the progressive decrease across sleep cycles, indicating that a form of homeostatic regulation of delta activity is present also in this subcortical structure. Hippocampal sleep was also characterized by: i) a lower relative power in the slow oscillation range during NREM sleep compared to the scalp EEG; ii) a flattening of the time course of the very low frequencies (up to 1 Hz) across sleep cycles, with relatively high levels of power even during REM sleep; iii) a decrease of power in the beta band during REM sleep, at odds with the typical increase of power in the cortical recordings. Conclusions/Significance Our data imply that cortical slow oscillation is attenuated in the hippocampal structures during NREM sleep. The most peculiar feature of hippocampal sleep is the increased synchronization of the EEG rhythms during REM periods. This state of resonance may have a supportive role for the processing/consolidation of memory.

Neuroscientists’ efforts to better understand the underlying processes of human consciousness are growing in a variety of multidisciplinary approaches. Relevant within these are the studies aimed at exploring the physiological substratum of the propagation and reduction of cerebral—namely, corticocortical—communication flows. However, the preferential direction of the information flow between brain hemispheres is as yet largely unknown. It is the aim of the present research to study the communication flows between brain hemispheres, their directionality, and their regional variations across wake--sleep states. A second aim is to investigate the possibility of an association between different brain rhythms and different preferred directions of the information flow. Scalp electroencephalograms (EEGs) were recorded in 10 normal volunteers from wakefulness to early sleep stages (viz., resting wakefulness, sleep stages 2 and 4, and rapid eye movement [REM] of the first sleep cycle). EEG rhythms of interest were delta (1--4 Hz), theta (5--7 Hz), alpha (8--11 Hz), sigma (12--15 Hz), and beta (16--30 Hz). The direction of the interhemispheric information flow was evaluated by computing directed transformation function from these EEG rhythms. Interhemispheric directional flows varied as a function of the state of consciousness (wake and early sleep stages) and in relation to different cerebral areas. Across wake to sleep states, we found that delta and beta rhythms convey interhemispheric signals with opposite directions: preferred right to left hemisphere direction for delta and left to right for beta rhythms. A log correlation confirmed that the trend of low to high EEG frequencies—traditionally associated with an increasing state of vigilance—was significantly related to the direction of the communication flow from the left to right hemisphere. This evidence might open the way for a variety of research lines on different psychophysiological and pathological conditions.

In recent years a growing number of people have begun to use mobile phone technology. This phenomenon has raised questions and doubts about possible effects on users' brains. This literature review focuses on the human electrophysiological and neuro-metabolic effects of mobile phone (MP)-related electromagnetic fields (EMFs) published in the last 10 years. To this end, all relevant papers have been reported and, subsequently, a literature selection has been carried out by taking several criteria into account, such as: blind techniques, randomization or counter-balancing of conditions and subjects, detail of exposure characteristics and the statistical analyses used. As a result, only the studies meeting the selection criteria have been described, evaluated and discussed further. The main goal of this review is to provide a clear scenario of the most reliable experiments carried out over the last decade and to offer a critical point of view in their evaluation. It is concluded that MP-EMFs may influence normal physiology through changes in cortical excitability and that in future research particular care should be dedicated to both methodological and statistical control, the most relevant criteria in this research field.

Objective Electrical stimulation of the median nerve followed by a magnetic pulse on the primary motor cortex (M1) is effective to cause an increase in the amplitude of motor evoked potential (MEP) registered in the target muscle with the interstimulus interval (ISI) at 25 ms (paired associative stimulation, PAS). The aim of this study is to evaluate the reproducibility of PAS with ISI 25 (PAS25), assessed in two separate sessions. Intraindividual reliability of TMS measures was also evaluated. Methods Motor threshold of abductor pollicis brevis (APB), assessed at rest, and MEP amplitude of APB and abductor digiti minimi (ADM) were assessed before and after PAS25 in 18 healthy volunteers (nine males and nine females). Results Data showed a significant increase of MEP amplitude in the target muscle (APB) after PAS25 and a reproducibility of group effect in the two sessions, as assessed by ANOVA, but a lack of intraindividual reliability, as assessed by intraclass correlation coefficients (ICC). Conclusions The results underline the reproducibility of mean effects and the need to be careful when comparing the same subject on different days. Significance Electrical stimulation of the median nerve followed by a magnetic pulse delivered on M1 after 25 ms causes a reproducible increase in MEP amplitude, without showing an acceptable intraindividual reliability.

Quantitative analysis of EEG during wakefulness in AD/MCI patients shows a slowing of EEG rhytms, in terms of increase of delta activity and decrease of alpha activity. Some studies show differences in AD/MCI patients even in EEG sleep: an increase in stage 1, number and length of intra-night awakenings, a decrease of Slow Wave Sleep (SWS) and REM sleep. Given the strong relation (bidirectional) between EEG sleep and wakefullness rhythms, the objective of the study is to assess EEG topography during sleep (REM and NREM) and wakefulness, and to assess relationship between sleep EEG modifications and subsequent variations in wakefulness EEG. 8 patients AD, 13 MCI and 9 elderly healthy people performed one-night sleep PSG recordings (19 cortical electrods, EOG, EMG) and wakefulness EEG recordings (5 min with eyes open and 5 min with eyes closed). Analyses of EEG topography of wakefulness, REM and NREM sleep suggest significant differences between MCI groups vs. controls within the alpha band, in terms of lower EEG activity within this frequency range in patients in occipital and temporal derivations compared to controls. Although preliminary, data of EEG topography seems showing the same functional variations both in sleep and wakefulness. Hence, the observed slowing may be an electrophysiological evidence of neurodegenerative processes at a cortical level.