“The choice for death” and neurology

In the last decade, "end-of-life" issues have gained prominence in political and social debates in many countries. The deliberate ending of the life of a patient upon his/her own request has become a hotly contested topic. This paper discusses the implications of this debate and of corresponding policy and legal developments for neurology. We discuss the nomenclature of the "choices for death", euthanasia, doctor-assisted suicide and palliative care as well as the social dynamics underlying these developments. We suggest that we need a more nuanced and empirically based understanding of the process of the "choice for death and its implications for medical practice."     

What is available for case identification in autism research in mainland China?

Little is known about research on Autism Spectrum Conditions (ASC) in mainland China. The few available studies in mainland China have shown the screening and diagnostic instruments for ASC used in mainland China were different from the West. Literature on screening and diagnostic instruments and criteria were reviewed and current available instruments were identified and evaluated. Eight screening instruments and two diagnostic instruments were identified. The Clancy Autism Behaviour Scale (CABS), the Autism Behaviour Checklist (ABC) and the Childhood Autism Rating Scale (CARS) were the most frequently used instruments in mainland China. They were adopted from the West more than two decades ago for detecting individuals with Childhood Autism but not the whole autism spectrum. Standardised instruments need to be validated and adopted into autism research in mainland China.     

Modulation of brainstem reflexes induced by non-invasive brain stimulation: is there a future?

Kumru et al.(2019)have recently reported significant reduction of the R2 component of the trigeminal blink reflex following highfrequency(20 Hz)repetitive transcranial magnetic stimulation(rTMS)over the vertex in both,healthy subjects and in patients with spinal cord injury(SCI)(Figure 1).The modulatory influence of non-invasive brain stimulation(NIBS)on brainstem reflexes has been only scarcely studied.     

When is it appropriate to focus on protection in interventions for adolescents?

Assertions about the appropriateness of targeting risk or protective factors in interventions for adolescents must be qualified in terms of the outcomes and populations examined in studies and in terms of how risk and protection are measured. The cross-sectional and longitudinal relationships between protection and aggressive behavior found for 388 high-risk adolescents (81.7% male; 50.8% African American/other; average age, 14.5) with serious emotional disturbances in this study validated an intervention focus on protective factors.     

Long-term follow-up of vanishing tumors in the brain: How should a lesion mimicking primary CNS lymphoma be managed?

Objectives

The spontaneous disappearance of a tumor is referred to as a vanishing tumor. Most vanishing tumors in the brain are eventually diagnosed as malignant tumors or multiple sclerosis. However, their long-term clinical course remains unclear. This study aims to elucidate the management of vanishing tumors in the brain.

Patients and methods

We defined a vanishing tumor as a case in which the tumor spontaneously disappeared or decreased to less than 70% of the initial tumor volume before definitive diagnosis and treatment (other than steroid treatment). Ten cases of vanishing tumors are reviewed.

Results

Nine patients underwent biopsy at least once. Five patients, all of whom had malignant tumors (primary central nervous system lymphoma: 4, germinoma: 1) that recurred in 4–45 months (median: 7 months), underwent a second biopsy after the reappearance of the tumors. Five patients (tumefactive demyelinating lesion: 1, undiagnosed: 4) who had no relapse are alive, and their median follow-up time is 44 months. No cases have yet been reported of malignant brain tumors that recurred more than 5 years after spontaneous regression.

Conclusions

Patients with vanishing tumors should be followed up carefully by magnetic resonance imaging for at least 5 years, even after the disappearance of an enhancing lesion.     

Where is the brain in all of this?

Clinical Autonomic Research -     

The Prodromal Questionnaire: a case for IRT‐based adaptive testing of psychotic experiences?

Computerized adaptive tests (CATs) for positive and negative psychotic experiences were developed and tested in N = 5705 help‐seeking, non‐psychotic young individuals. Instead of presenting all items, CATs choose a varying number of different items during test administration depending on respondents' previous answers, reducing the average number of items while still obtaining accurate person estimates. We assessed the appropriateness of two‐parameter logistic models to positive and negative symptoms of the Prodromal Questionnaire (PQ), computed measurement precision of all items and resulting adaptive tests along psychotic dimensions by Real Data Simulations (RDS), and computed indices for criterion and predictive validities of the CATs. For all items, mean absolute differences between observed and expected response probabilities were smaller than 0.02. CAT‐POS predicted transition to psychosis and duration of hospitalization in individuals at‐risk for psychosis, and CAT‐NEG was suggestively related to later functioning. Regarding psychosis risk classifications of help‐seeking individuals, CAT‐POS performed less than the PQ‐16. Adaptive testing based on self‐reported positive and negative symptoms in individuals at‐risk for psychosis is a feasible method to select patients for further risk classification. These promising findings need to be replicated prospectively in a non‐selective sample that also includes non‐at‐risk individuals. Copyright © 2016 John Wiley & Sons, Ltd.     

The sodium in sodium oxybate: is there cause for concern?

Sodium oxybate (SO), the sodium salt of γ-hydroxybutyric acid, is one of the primary pharmacologic agents used to treat excessive sleepiness, disturbed nighttime sleep, and cataplexy in narcolepsy. The sodium content of SO ranges from 550 to 1640 mg at 3–9 g, given in two equal nightly doses. Clinicians are advised to consider daily sodium intake in patients with narcolepsy who are treated with SO and have comorbid disorders associated with increased cardiovascular (CV) risk, in whom sodium intake may be a concern. It remains unclear whether all patients with narcolepsy treated with SO should modify or restrict their sodium intake. No data are currently available specific to the sodium content or threshold of SO at which patients might experience increased CV risk. To appraise attributable risk, critical evaluation of the literature was conducted to examine the relationship between CV risk and sodium intake, narcolepsy, and SO exposure. The findings suggest that increased CV risk is associated with extremes of daily sodium intake, and that narcolepsy is associated with comorbidities that may increase CV risk in some patients. However, data from studies regarding SO use in patients with narcolepsy have shown a very low frequency of CV side effects (eg, hypertension) and no overall association with CV risk. In the absence of data that specifically address CV risk with SO based on its sodium content, the clinical evidence to date suggests that SO treatment does not confer additional CV risk in patients with narcolepsy.     

The primary brain vesicles revisited: are the three primary vesicles (forebrain/midbrain/hindbrain) universal in vertebrates?

It is widely held that three primary brain vesicles (forebrain, midbrain, and hindbrain vesicles) develop into five secondary brain vesicles in all vertebrates (von Baer's scheme). We reviewed previous studies in various vertebrates to see if this currently accepted scheme of brain morphogenesis is a rule applicable to vertebrates in general. Classical morphological studies on lamprey, shark, zebrafish, frog, chick, Chinese hamster, and human embryos provide only partial evidence to support the existence of von Baer's primary vesicles at early stages. Rather, they suggest that early brain morphogenesis is diverse among vertebrates. Gene expression and fate map studies on medaka, chick, and mouse embryos show that the fates of initial brain vesicles do not accord with von Baer's scheme, at least in medaka and chick brains. The currently accepted von Baer's scheme of brain morphogenesis, therefore, is not a universal rule throughout vertebrates. We propose here a developmental hourglass model as an alternative general rule: Brain morphogenesis is highly conserved at the five-brain vesicle stage but diverges more extensively at earlier and later stages. This hypothesis does not preclude the existence of deep similarities in molecular prepatterns at early stages.     

How 'generalized' is the 'slowed processing' in SLI? The case of visuospatial attentional orienting

The study was designed to assess the speed and efficiency of visuospatial attentional orienting and the speed of visual processing and motor response in school-age children diagnosed with specific language impairment (SLI). Fifteen participants with SLI (7-15 years old) and their gender- and age-matched normally developing peers performed two formats of a simple visual discrimination task, one requiring the use of attentional orienting for accurate performance, and the other not requiring shifts of attention. The SLI group was characterized by (a) slower visual processing, and (b) slower motor response, but (c) similar attentional orienting speed, relative to the control group. The results are discussed in relation to the ‘generalized slowing hypothesis’ in SLI and the neural underpinning of visuospatial attentional orienting and SLI.     

The neural mechanisms of object working memory: what is where in the infant brain?

The question of how representational capacities develop in humans has been engaging cognitive psychologists for decades. Looking time studies have explored when infants start to show signs of perceiving and remembering the properties of specific objects at specific locations. Here we integrate these findings into the neuroscientific framework of human visual working memory. We suggest that the development of a system involving the temporal cortex, thalamic and hippocampal structures and possibly the dorsolateral prefrontal cortex (later in development) can account for these behavioral results. Our explanation differs from most of the current approaches in developmental science as we put less emphasis on the contribution of lateral prefrontal areas. We discuss shortcomings of the theories that propose a functional subdivision of these areas and their difficulty in accounting for results from monkey lesion and infant studies. We believe that this shift in focus is desirable both in light of what recent results on medial temporal lobe processing reveal about object working memory, and given how well these results fit the behavioral developmental data.     

EMG artifact in brain death electroencephalogram,is it a cry of “medullary death”?

The Uniform Determination of Death Act (UDDA) defines death as irreversible cessation of the functions of the entire brain including the brainstem. Many individuals meeting the clinical criteria of brain death can be documented to have some residual sub-cortical and brainstem function on careful testing. Determination of brain death still remains a persistently unresolved issue in health law and bioethics. The determination of brain death is clinical and involves testing for the integrity of brainstem functions. Documentation of irreversible cessation of brainstem functions when the cause of coma is established is usually sufficient to make a diagnosis of brain death. Confirmatory tests like four-vessel angiogram and electroencephalogram (EEG) are required in cases where the clinical testing is inconclusive or unreliable. EEG criteria for electrocerebral silence (ECS) is absence of any detectable cortical activity above 2 μV in a study performed as per the guidelines developed by the American Electroencephalographic Society. EEG studies carried out for ECS are at times contaminated by electromyographic (EMG) artifacts reflecting scalp motor unit activity. A secure EEG diagnosis of ECS cannot be made in such cases. What exactly is the relevance of scalp EMG activity in these clinically brain dead patients? What is the mechanism of generation of this spontaneous scalp EMG activity and how can the diagnosis of brain death be secured in these patients? These issues are explored in this article by highlighting a case.