Conservative treatments of children with episodic tension–type headache

Objective We aimed to assess the effectiveness of conservative treatments in children with tension–type headaches (TTH). Method We searched Medline, Embase and the Cochrane Library and performed reference checking. Two independent authors assessed trial quality and extracted data. Analysis was carried out according to type of intervention. Results In total we included 11 trials (427 TTH patients, age between 7–18 years) in this review. None of the studies were considered to be of high quality. Eight studies evaluated the effectiveness of relaxation training. Four studies included a waiting list or no treatment control group and in one study a placebo was used. Conclusion We found conflicting evidence about the effectiveness of relaxation therapy when compared with no treatment or other treatments, with Relative Risks varying from 1.4 (0.6–3.2) to 10.6 (1.6–71.3). With regard to all other interventions evaluated (such as biofeedback, cognitive therapy or flupirtin) no evidence is found for or against their effectiveness.     

Hippocampal place cells: the "where" of episodic memory?

Neuropsychologists have clearly implicated the hippocampus in the consolidation of memory, particularly episodic memory, the mental replay of past experiences. When recorded from behaving animals, by far the most obvious firing pattern of the primary neurons of the hippocampus is the place field: a cell tends to fire only when the animal's head is in a particular part of its environment. It seems reasonable to suspect that the primary firing correlate of the primary neurons of a structure should underlie the primary function of that structure as revealed by behavioral lesion experiments. However, we are currently still at a loss to explain how the firing of hippocampal neurons contributes to hippocampal function. This review seeks to examine the commonalities between place cells and episodic memory, and posits that an analogy can be made between the stabilization of place fields and the consolidation of memory.     

Are all judgments created equal? An fMRI study of semantic and episodic metamemory predictions

Metamemory refers to the ability of individuals to monitor and control their own memory performance. Although little theoretical consideration of the possible differences between the monitoring of episodic and of semantic knowledge has been published, results from patient and drug studies that used the “feeling of knowing” (FOK) paradigm show a selective impairment in the accuracy of episodic monitoring but not in its semantic counterpart. Similarly, neuroimaging studies provide indirect evidence for separate patterns of activation during episodic or semantic FOKs. However, the semantic-episodic distinction hypothesis has not been directly addressed. In the current event-related fMRI study, we used a within-subject, within-experiment comparison of the monitoring of semantic and episodic content. Whereas the common neural correlates of episodic and semantic FOKs observed in this study generally replicate the previous neuroimaging findings, several regions were found to be differentially associated with each task. Activity of the right inferior frontal gyrus was modulated by the semantic-episodic factor only during the negative predictions of retrieval, suggesting that negative predictions are based on partially distinct mechanisms during each task. A posterior midline network, known to be activated during episodic retrieval, was activated during episodic and not semantic monitoring, suggesting that episodic FOKs rely, to some extent, on common episodic retrieval processes. These findings suggest that theoretical accounts of the etiology and function of FOKs may benefit from incorporating the prediction directionality (positive/negative) and the memory domain (semantic/episodic) distinctions.     

Dreaming and episodic memory: a functional dissociation?

The activity that takes place in memory systems during sleep is likely to be related to the role of sleep in memory consolidation and learning, as well as to the generation of dream hallucinations. This study addressed the often-stated hypothesis that replay of whole episodic memories contributes to the multimodal hallucinations of sleep. Over a period of 14 days, 29 subjects kept a log of daytime activities, events, and concerns, wrote down any recalled dreams, and scored the dreams for incorporation of any waking experiences. While 65% of a total of 299 sleep mentation reports were judged to reflect aspects of recent waking life experiences, the episodic replay of waking events was found in no more than 1-2% of the dream reports. This finding has implications for understanding the unique memory processing that takes place during the night and is consistent with evidence that sleep has no role in episodic memory consolidation.     

Can episodic memory tasks differentiate semantic dementia from Alzheimer's disease?

The performance of two groups of patients with semantic dementia (SD), with predominant right (SDR) and left temporal lobe atrophy (SDL), was contrasted with that of cases with probable Alzheimer's disease (AD) on a range of standard episodic memory tasks. While the SDL group achieved a good score on a composite visual, but not a verbal, episodic memory measure, the AD and SDR groups were equivalently impaired at visual and verbal memory. The SD, but not the AD, groups were, by definition, impaired on simple tests of semantic memory. Standard verbal episodic memory tests, therefore, failed to discriminate patients with SD from those with probable AD and even visual memory tests may result in misclassification of SDR cases.     

Does lateral parietal cortex support episodic memory? Evidence from focal lesion patients

Although neuroimaging and human lesion studies agree that the medial parietal region plays a critical role in episodic memory, many neuroimaging studies have also implicated lateral parietal cortex, leading some researchers to suggest that the lateral region plays a heretofore underappreciated role in episodic memory. Because there are very few extant lesion data on this matter, we examined memory in six cases of focal lateral parietal damage, using both clinical and experimental measures, in which we distinguished between recollection and familiarity. The patients did not have amnesia, but they did show evidence of disrupted recollection on an anterograde memory task. Although the exact mechanisms remain to be elucidated, lateral parietal damage appears to impair some aspects of episodic memory.     

Neuron-specific Sumo1–3 knockdown in mice impairs episodic and fear memories

Background

Growing evidence suggests that small ubiquitin-like modifier (SUMO) conjugation plays a key role in brain plasticity by modulating activity-dependent synaptic transmission. However, these observations are based largely on cell culture experiments. We hypothesized that episodic and fear memories would be affected by silencing SUMO1–3 expression.

Methods

To investigate the role of SUMO conjugation in neuronal functioning in vivo, we generated a novel Sumo transgenic mouse model in which a Thy1 promoter drives expression of 3 distinct microRNAs to silence Sumo1–3 expression, specifically in neurons. Wild-type and Sumo1–3 knockdown mice were subjected to a battery of behavioural tests to elucidate whether Sumoylation is involved in episodic and emotional memory.

Results

Expression of Sumo1–3 microRNAs and the corresponding silencing of Sumo expression were particularly pronounced in hippocampal, amygdala and layer V cerebral cortex neurons. The Sumo knockdown mice displayed anxiety-like responses and were impaired in episodic memory processes, contextual and cued fear conditioning and fear-potentiated startle.

Limitations

Since expression of Sumo1–3 was silenced in this mouse model, we need to verify in future studies which of the SUMO paralogues play the pivotal role in episodic and emotional memory.

Conclusion

Our results indicate that a functional SUMO conjugation pathway is essential for emotionality and cognition. This novel Sumo knockdown mouse model and the technology used in generating this mutant may help to reveal novel mechanisms that underlie a variety of neuropsychiatric conditions associated with anxiety and impairment of episodic and emotional memory.     

Autobiographical and episodic memory--one and the same? Evidence from prefrontal activation in neuroimaging studies

Laboratory investigations of episodic memory often require participants to encode and later retrieve lists of items (words, pictures, or faces). The underlying assumption is that recollection of items from the list is analogous to recollection of events from one's past, i.e. autobiographical re-experiencing. Functional neuroimaging studies of episodic memory have provided extensive evidence suggesting that regions of the prefrontal cortex (PFC) play a role in episodic memory retrieval. A review of PFC activations reported in imaging studies of autobiographical memory and matched sub-sets of list-learning episodic memory studies reveals patterns of similarity but also substantial differences. Episodic memory studies often report activations in the right mid-dorsolateral PFC, but such activations are absent in autobiographical memory studies. Additionally, activations in the ventromedial PFC, primarily on the left, are almost invariably found in autobiographical memory studies, but rarely occur in studies of episodic memory. It is suggested that these two regions mediate different modes of post-retrieval monitoring and verification. Autobiographical memory relies on quick intuitive 'feeling of rightness' to monitor the veracity and cohesiveness of retrieved memories in relation to an activated self-schema. Episodic memory for lists requires more conscious elaborate monitoring to avoid omissions, commissions and repetitions. The present analysis suggests that care and caution should be exercised in extrapolating from the way we recollect 'events' from a list learned in the laboratory to the way we recollect events from our lives.     

Cueing the personal future to reduce discounting in intertemporal choice: Is episodic prospection necessary?

How does the ability to imagine detailed future experiences (i.e., episodic prospection) contribute to choices between immediate and delayed rewards? Individuals with amnesia do not show abnormally steep discounting in intertemporal choice, suggesting that neither medial temporal lobe (MTL) integrity nor episodic prospection is required for the valuation of future rewards (Kwan et al. ( ), Hippocampus, 22:1215‐1219; Kwan et al. (2013), J Exp Psychol, 142:1355‐1369 2013). However, hippocampally mediated episodic prospection in healthy adults reduces the discounting of future rewards (Peters and Büchel (2010), Neuron, 66:138‐148; Benoit et al. (2011), J Neurosci, 31:6771‐6779), raising the possibility that MTL damage causes more subtle impairments to this form of decision‐making than noted in previous patient studies. Intertemporal choice appears normal in amnesic populations, yet they may be unable to use episodic prospection to adaptively modulate the value assigned to future rewards. To investigate how the extended hippocampal system, including the hippocampus and related MTL structures, contributes to the valuation of future rewards, we compared the performance of six amnesic cases with impaired episodic prospection to that of 20 control participants on two versions of an intertemporal choice task: a standard discounting task, and a cued version in which cues prompted them to imagine specific personal future events temporally contiguous with the receipt of delayed rewards. Amnesic individuals' intertemporal choices in the standard condition were indistinguishable from those of controls, replicating previous findings. Surprisingly, performance of the amnesic cases in the cued condition indicates that amnesia does not preclude flexible modulation of choices in response to future event cues, even in the absence of episodic prospection. Cueing the personal future to modulate decisions appears to constitute a less demanding or a qualitatively different (e.g., personal semantic) form of prospection that is not as sensitive to MTL damage as prospective narrative generation. © 2015 Wiley Periodicals, Inc.     

Verbal episodic memory in 426 multiple sclerosis patients: impairment in encoding, retrieval or both?

Episodic memory is frequently impaired in multiple sclerosis (MS) patients but the exact nature of the disorder is controversial. It was initially thought to be due to a retrieval deficit but some studies have demonstrated an encoding deficit, which could be linked to a slowing of information processing speed or to a deficit in elaboration of strategies. The main objective of this study is to assess the prevalence and the nature of verbal episodic memory (VEM) impairment in MS patients. We retrieved memory performances of 426 patients [314 F–112 M; mean age: 46.1 years; median Expanded Disability Status Scale (EDSS) score: 3.1] from a neuropsychological data base. VEM was assessed using the 16 words RL-RI 16 test. 66% MS patients present at least one recall impaired in VEM (37.2% from 2 to 5 recall). 14.2% MS patients present an impairment in encoding phase. We observed that 5% of patients presented recognition difficulties. Correlations were observed between VEM performances and EDSS, and disease duration but no group effect (ANOVA) is observed between form of MS and VEM performances. These results confirm the high prevalence of VEM impairment in MS patients. Deficits affect mainly information retrieval in early stage MS patients and are then linked to encoding as disability increases. Storage disorders are infrequent, so cognitive rehabilitation with mental imaging could be effective in MS patients.     

Impaired motor speed, visuospatial episodic memory and verbal fluency characterize cognition in long-term stroke survivors: the Tromsø Study

The cognitive function after stroke is examined in acute and subacute phase, but poorly characterized in long-term stroke survivors. This paper discusses cognitive function among long-term stroke survivors, with matched stroke-free subjects, based on a population survey. General cognition, verbal, executive and visuospatial function, memory, attention, and motor speed were tested as well as motor function in upper extremities. Stroke survivors and controls were most effectively discriminated by means of motor speed, followed by visuospatial episodic memory and verbal fluency. This pattern of cognitive disturbances may be a consequence of cerebral lesions in frontal subcortical areas, and is different from Alzheimer's disease.     

Next of kin’s Reactions to Results of Functional Neurodiagnostics of Disorders of Consciousness: a Question of Information Delivery or of Differing Epistemic Beliefs?

Our recent publication in Neuroethics re-constructed the perspectives of family caregivers of patients with disorders of consciousness (DOC) on functional neurodiagnostics (Schembs et al., Neuroethics, 2020). Two papers criticized some of our methodological decisions (Peterson, Neuroethics, 2020; Andersen et al., Neuroethics, 2020) and commented on some conclusions. In this commentary, we would like to further explain our methodological decisions. Despite the limitations of our findings, which we readily acknowledged, we continue to think they entail valid hypotheses that need further investigation. We conclude that some caregivers with high hopes for the recovery of their loved ones with DOC will most likely not consider results of functional neuroimaging as guiding information for treatment decisions, despite efforts taken to deliver information to them. Caregivers of that type might argue that such test-results are not a reliable source of information for the judgement of whether their loved one is likely going to recover or not (prognosis). We introduce the concept of epistemic beliefs to formulate this hypothesis and suggest that future qualitative studies in this area should be aware of such beliefs when investigating the effects of functional neurodiagnostics on knowledge communication and shared decision making for patients with DOC.

     

Effect of long-term low dose of aspirin on severity of disease following onset of acute cerebral infarction

IN T R O D U C T IO N P revention is a very im portant m easure to reduce the incidence of cerebrovasculardisease. Aspirin is a w ell-accepted effective drug in prevention ofcerebrovasculardisease [1-3]. Although the prevention of ischem ic cerebrovascula…     

Does the place of treatment influence the quality of life of schizophrenics?

OBJECTIVE: Chronically mentally ill patients in community mental health care report a better quality of life (QOL) than those in long-term hospital care, which suggests that the treatment setting per se influences their QOL. METHOD: In a region where both treatment settings are of a comparable high standard, we assessed the QOL of 96 schizophrenic patients from these two treatment settings, and the factors which most influenced their QOL. RESULTS: Community-care patients reported a better QOL than long-term hospital-care patients. However, when other factors influencing QOL were included in a regression analysis, the place of treatment was no longer significant, but rather the social support, the severity of the illness, educational level and certain illness concepts. CONCLUSION: It is probably not the place per se which influences the QOL, but apart from personal, sociodemographic and illness-related factors, the amount of social support that is provided in different settings.     

Trajectories of brain development: point of vulnerability or window of opportunity?

Brain development is a remarkable process. Progenitor cells are born, differentiate, and migrate to their final locations. Axons and dendrites branch and form important synaptic connections that set the stage for encoding information potentially for the rest of life. In the mammalian brain, synapses and receptors within most regions are overproduced and eliminated by as much as 50% during two phases of life: immediately before birth and during the transitions from childhood, adolescence, to adulthood. This process results in different critical and sensitive periods of brain development. Since Hebb (1949) first postulated that the strengthening of synaptic elements occurs through functional validation, researchers have applied this approach to understanding the sculpting of the immature brain. In this manner, the brain becomes wired to match the needs of the environment. Extensions of this hypothesis posit that exposure to both positive and negative elements before adolescence can imprint on the final adult topography in a manner that differs from exposure to the same elements after adolescence. This review endeavors to provide an overview of key components of mammalian brain development while simultaneously providing a framework for how perturbations during these changes uniquely impinge on the final outcome.