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Sleep quality and its association with cognition has been widely studied in some neurodegenerative diseases, but less is known about this association in spinal muscular atrophy (SMA). In adult SMA (n = 21) patients and age-matched controls (n = 23), we assessed subjectively measured sleep quality and daytime somnolence. Cognition was assessed with a multi-domain neuropsychological battery. Further, we investigated the association between clinical functional scores and sleep questionnaire scores. Among SMA patients, better motor and limb function was associated with better subjective sleep quality (p’s< 0.05). Clinicians should consider sleep quality in patient care and future studies are needed to better understand these relationships.

Metacognition refers to the ability to monitor and control one's cognitive processes which plays an important role in decision-making throughout the lifespan. It is still debated whether metacognitive abilities decline with age. Recent neuroimaging evidence suggests the existence of domain-specific mechanisms underlying metacognition and it is possible that age-related decline follows domain-specific trajectories across cognitive functions. Event-related potential (ERP) research has identified neural markers of performance monitoring. The error-related negativity (ERN) and the error positivity (Pe) are electrophysiological correlates of error detection and error awareness, respectively. However, ERP differences across cognitive domains have not been yet investigated. In the current study, thirty-eight young adults and thirty-seven older adults completed a classic Flanker Task (perceptual) and an adapted memory-based version during EEG recordings. Univariate and multivariate analyses were conducted to explore domain-specific mechanisms of error monitoring ERPs and age group differences. No difference in ERN amplitude was found between young and older adults and across domains. ERN peaked earlier in the perceptual domain than the memory domain. ΔERN was larger for the memory domain than the perceptual domain. Pe was smaller in older adults but similar across domains. Memory Pe peaked earlier in young adults than older adults ΔPe was larger for perceptual than memory flanker. Memory Pe peaked earlier in young as compared to older adults. During the task, ERN decreased in young but not in older adults. Memory Pe decreased in young adults but increased in older adults while no significant change in perceptual Pe was found. Multivariate analyses of whole scalp data support cross domain differences. These findings suggest that error monitoring may rely on domain-specific mechanisms. Moreover, we speculate that reduced error awareness may be associated with sensory decline in aging, as indicated by learning effects specific to the memory domain.

Error monitoring allows for the efficient performance of goal-directed behaviors and successful learning. Furthermore, error monitoring as a metacognitive ability may play a crucial role for neuropsychological interventions, such as rehabilitation. In the past decades, research has suggested two electrophysiological markers for error monitoring: the error-related negativity (ERN) and the error positivity (Pe), thought to reflect, respectively, error detection and error awareness. Studies on several neurological diseases have investigated the alteration of the ERN and the Pe, but these findings have not been summarized. Accordingly, a systematic review was conducted to understand what neurological conditions present alterations of error monitoring event-related potentials and their relation with clinical measures. Overall, ERN tended to be reduced in most neurological conditions while results related to Pe integrity are less clear. ERN and Pe were found to be associated with several measures of clinical severity. Additionally, we explored the contribution of different brain structures to neural networks underlying error monitoring, further elaborating on the domain-specificity of error processing and clinical implications of findings. In conclusion, electrophysiological signatures of error monitoring could be reliable measures of neurological dysfunction and a robust tool in neuropsychological rehabilitation.

This is the host page for the content from the BSPID 2021 conference. On this page are the presentations and posters from our event on 17th June 2021

Plants in nature are constantly exposed to organisms that touch them and wound them. A highly conserved response to these stimuli is a rapid collapse of membrane potential (i.e. a decrease of electrical field strength across membranes). This can be coupled to the production and/or action of jasmonate or ethylene. Here, the various types of electrical signals in plants are discussed in the context of hormone responses. Genetic approaches are revealing genes involved in wound-induced electrical signalling. These include clade 3 GLUTAMATE RECEPTOR-LIKE (GLR) genes, Arabidopsis H+ -ATPases (AHAs), RESPIRATORY BURST OXIDASE HOMOLOGUEs (RBOHs), and genes that determine cell wall properties. We briefly review touch- and wound-induced increases in cytosolic Ca2+ concentrations and their temporal relationship to electrical activities. We then look at the questions that need addressing to link mechanostimulation and wound-induced electrical activity to hormone responses. Utilizing recently published results, we also present a hypothesis for wound-response leaf-to-leaf electrical signalling. This model is based on rapid electro-osmotic coupling between the phloem and xylem. The model suggests that the depolarization of membranes within the vascular matrix triggered by physical stimuli and/or chemical elicitors is linked to changes in phloem turgor and that this plays vital roles in leaf-to-leaf electrical signal propagation.

Cognitive abilities are often affected in progressive neurodegenerative disorders, but there is a lack of understanding about whether spinal muscular atrophy (SMA) patients experience cognitive deficits and, if so, whether they are associated with clinical factors. A sample of 22 type III SMA patients and 22 healthy controls completed a comprehensive neuropsychological battery, including tests in memory, executive function, language, visuospatial, and global cognitive functioning. Clinical severity was assessed using the Hammersmith Functional Motor Scale, the Revised Upper Limb Module and the Six Minute Walk Test. SMA patients showed poorer performance in visuospatial abilities, executive functions and language as compared to healthy controls. In the SMA sample, patients with greater motor difficulties had lower performance in attention, but higher performance in measures of language, verbal fluency, and memory. In men, but not women, cognitive test performance was associated with motor functioning. Our findings showing cognitive changes in SMA type III may reflect the presence of intrinsic brain pathology and cognitive adaptation mechanisms following physical dysfunction, which may be mediated by other factors, such as sex.

Objective:This study explored mental rotation (MR) performance in patients with myotonic dystrophy 1 (DM1), an inherited neuromuscular disorder dominated by muscular symptoms, including muscle weakness and myotonia. The aim of the study was twofold: to gain new insights into the neurocognitive mechanisms of MR and to better clarify the cognitive profile of DM1 patients. To address these aims, we used MR tasks involving kinds of stimuli that varied for the extent to which they emphasized motor simulation and activation of body representations (body parts) versus visuospatial imagery (abstract objects). We hypothesized that, if peripheral sensorimotor feedback system plays a pivotal role in modulating MR performance, then DM1 patients would exhibit more difficulties in mentally rotating hand stimuli than abstract objects.Method:Twenty-four DM1 patients and twenty-four age- and education-matched control subjects were enrolled in the study and were required to perform two computerized MR tasks involving pictures of hands and abstract objects.Results:The analysis of accuracy showed that patients had impaired MR performance when the angular disparities between the stimuli were higher. Notably, as compared to controls, patients showed slower responses when the stimuli were hands, whereas no significant differences when stimuli were objects.Conclusion:The findings are coherent with the embodied cognition view, indicating a tight relation between body- and motor-related processes and MR. They suggest that peripheral, muscular, abnormalities in DM1 lead to alterations in manipulation of motor representations, which in turn affect MR, especially when body parts are to mentally rotate.

The second messenger calcium plays a key role in conveying specificity of signalling pathways in plant cells. Specific calcium signatures are decoded to generate correct gene expression responses and amplification of calcium signatures is vital to this process. It is not known: (1) if this amplification is an intrinsic property of all calcium-regulated gene expression responses and whether all calcium signatures have the potential to be amplified, and (2) how does a given calcium signature maintain specificity in cells containing a great number of transcription factors (TFs) and other proteins with the potential to be calcium-regulated? The work presented here uncovers the design principle by which it is possible to decode calcium signals into specific changes in gene transcription in plant cells. Regarding the first question, we found that the binding mechanism between protein components possesses an intrinsic property that will nonlinearly amplify any calcium signal. This nonlinear amplification allows plant cells to effectively distinguish the kinetics of different calcium signatures to produce specific and appropriate changes in gene expression. Regarding the second question, we found that the large number of calmodulin (CaM)-binding transcription factors (TFs) or proteins in plant cells form a buffering system such that the concentration of an active CaM-binding TF is insensitive to the concentration of any other CaM-binding protein, thus maintaining specificity. The design principle revealed by this work can be used to explain how any CaM-binding TF decodes calcium signals to generate specific gene expression responses in plant cells via transcription.

INTRODUCTION: Neuromuscular diseases may be of neuropsychological interest insofar as they may affect representations based on embodied cognition theories. Previous studies have shown impaired ability to recognize facial emotions and an association between facial emotion recognition and visuospatial abilities in myotonic dystrophy type 1 (DM1) patients. Here we examined the ability of both DM1 and DM2 patients to recognize emotions expressed by body postures and its relation, and their association with cognitive performance.METHODS: Participants included 34 DM1 patients, 8 DM2 patients, and 24 healthy control subjects. Emotional recognition ability was assessed through two computerized matching tasks (face and bodies). A neuropsychological battery was used to measure cognition in three domains and global cognition. We used univariate and adjusted linear regression models to investigate the association between cognition and emotion recognition performance.RESULTS: DM patients (combined DM1 and DM2) performed worse on emotional facial expression (p = .006) and body posture (p = .004) accuracy measures than healthy controls. In linear regression models, DM patients' facial expression accuracy was associated with executive function (p = .013) and visuospatial (p < .001) z-scores. Body posture accuracy was associated with visuospatial (p = .001) and memory (p = .012) z-scores. There were no associations among controls or between cognition and reaction time.DISCUSSION: These findings suggest that impaired emotional recognition among DM patients is also extended to emotions conveyed by body postures. Consistent with embodied cognition theories, people affected in their body and its movement may have impaired sensorimotor representation in ways that have yet to be fully understood.

Plants need to sense increases in temperature to be able to adapt their physiology and development to survive; however, the mechanisms of heat perception are currently relatively poorly understood. Here we demonstrate that in response to elevated temperature, the free calcium concentration of the stroma of chloroplasts increases. This response is specific to the chloroplast, as no corresponding increase in calcium is seen in the cytosol. The chloroplast calcium response is dose dependent above a threshold. The magnitude of this calcium response is dependent upon absolute temperature, not the rate of heating. This response is dynamic: repeated stimulation leads to rapid attenuation of the response, which can be overcome by sensitization at a higher temperature. More long-term acclimation to different temperatures resets the basal sensitivity of the system, such that plants acclimated to lower temperatures are more sensitive than those acclimated to higher temperatures. The heat-induced chloroplast calcium response was partially dependent upon the calcium-sensing receptor CAS which has been shown previously to regulate other chloroplast calcium signaling responses. Taken together, our data demonstrate the ability of chloroplasts to sense absolute high temperature and produce commensurately quantitative stromal calcium response, the magnitude of which is a function of both current temperature and stress history.

Lack of awareness about disease, its symptoms and consequences, also termed anosognosia, is a common feature of Alzheimer’s disease (AD). It has been hypothesized that memory disorder may be a key contributing factor to anosognosia, with people with AD not being able to update their personal information about performance and relying on older consolidated material about ability. This potentially outdated sense of self has been named, as a metaphor, the petrified self. In the current review, evidence from the past 10 years in relation to this concept is critically appraised. In particular, focus is given to empirical evidence produced on anterograde memory deficits about performance, the profile of autobiographical retrograde memory loss and the role of frontal lobes in anosognosia in AD. Finally, wider consequences of this metaphor for the understanding of selfhood in dementia are discussed.

Calcium plays a key role in determining the specificity of a vast array of signalling pathways in plants. Cellular calcium elevations with different characteristics (calcium signatures) carry information on the identity of the primary stimulus, ensuring appropriate downstream responses. However, the mechanism for decoding calcium signatures is unknown. To determine this, decoding of the salicylic acid (SA)-mediated plant immunity signalling network controlling gene expression was examined. A dynamic mathematical model of the SA-mediated plant immunity network was developed. This model was used to predict responses to different calcium signatures; these were validated empirically using quantitative real-time PCR to measure gene expression. The mechanism for decoding calcium signatures to control expression of plant immunity genes enhanced disease susceptibility 1 (EDS1) and isochorismate synthase 1 (ICS1) was identified. Calcium, calmodulin, calmodulin-binding transcription activators (CAMTA)3 and calmodulin binding protein 60g (CBP60g) together amplify each calcium signature into three active signals, simultaneously regulating expression. The time required for calcium to return to steady-state level also quantitatively regulates gene expression. Decoding of calcium signatures occurs via nonlinear interactions between these active signals, producing a unique response in each case. Key properties of the calcium signatures are not intuitive, exemplifying the importance of mathematical modelling approaches. This approach can be applied to identifying the decoding mechanisms of other plant calcium signalling pathways.

The application of diffuse reflectance UV–VIS–NIR spectroscopy is proposed to differentiate 20 office paper samples, which had been deemed similar by a preliminary visual examination under several different lighting sources. The samples were firstly screened on the basis of the qualitative appearance of their spectra. A further discrimination was obtained by taking into account three parameters: the average reflectivity of the paper samples in the range 680–900 nm, and the integrated intensity of the absorption peak in the UV range at 272 nm and at 360 nm. The homogeneity of these parameters on both sides of the paper sheets was assessed, detecting a very uniform distribution of the optical brighteners. A special focus was posed on the determination of the discriminative power, in order to give a quantitative parameter on the proposed procedure, which is important when reporting results to the Court. The remarkable achievement of differentiating all the examined samples was obtained by UV–VIS spectroscopy, a very less expensive technique which is readily available in practically all forensic laboratories.