Exploring alterations in sensory pathways in migraine

Background Migraine is a neurological disorder characterized by intense, debilitating headaches, often coupled with nausea, vomiting and sensitivity to light and sound. Whilst changes in sensory processes during a migraine attack have been well-described, there is growing evidence that even between migraine attacks, sensory abilities are disrupted in migraine. Brain imaging studies have investigated altered coupling between areas of the descending pain modulatory pathway but coupling between somatosensory processing regions between migraine attacks has not been properly studied. The aim of this study was to determine if ongoing functional connectivity between visual, auditory, olfactory, gustatory and somatosensory cortices are altered during the interictal phase of migraine. Methods To explore the neural mechanisms underpinning interictal changes in sensory processing, we used functional magnetic resonance imaging to compare resting brain activity patterns and connectivity in migraineurs between migraine attacks (n = 32) and in healthy controls (n = 71). Significant differences between groups were determined using two-sample random effects procedures (p < 0.05, corrected for multiple comparisons, minimum cluster size 10 contiguous voxels, age and gender included as nuisance variables). Results In the migraine group, increases in infra-slow oscillatory activity were detected in the right primary visual cortex (V1), secondary visual cortex (V2) and third visual complex (V3), and left V3. In addition, resting connectivity analysis revealed that migraineurs displayed significantly enhanced connectivity between V1 and V2 with other sensory cortices including the auditory, gustatory, motor and somatosensory cortices. Conclusions These data provide evidence for a dysfunctional sensory network in pain-free migraine patients which may be underlying altered sensory processing between migraine attacks.

A New Player in the Hippocampus: A Review on VGLUT3+ Neurons and Their Role in the Regulation of Hippocampal Activity and Behaviour

Glutamate is the most abundant excitatory amino acid in the central nervous system. Neurons using glutamate as a neurotransmitter can be characterised by vesicular glutamate transporters (VGLUTs). Among the three subtypes, VGLUT3 is unique, co-localising with other “classical” neurotransmitters, such as the inhibitory GABA. Glutamate, manipulated by VGLUT3, can modulate the packaging as well as the release of other neurotransmitters and serve as a retrograde signal through its release from the somata and dendrites. Its contribution to sensory processes (including seeing, hearing, and mechanosensation) is well characterised. However, its involvement in learning and memory can only be assumed based on its prominent hippocampal presence. Although VGLUT3-expressing neurons are detectable in the hippocampus, most of the hippocampal VGLUT3 positivity can be found on nerve terminals, presumably coming from the median raphe. This hippocampal glutamatergic network plays a pivotal role in several important processes (e.g., learning and memory, emotions, epilepsy, cardiovascular regulation). Indirect information from anatomical studies and KO mice strains suggests the contribution of local VGLUT3-positive hippocampal neurons as well as afferentations in these events. However, further studies making use of more specific tools (e.g., Cre-mice, opto- and chemogenetics) are needed to confirm these assumptions.

Distinct mechanoreceptor pezo-1 isoforms modulate food intake in the nematode Caenorhabditis elegans

Two PIEZO mechanosensitive cation channels, PIEZO1 and PIEZO2, have been identified in mammals, where they are involved in numerous sensory processes. While structurally similar, PIEZO channels are expressed in distinct tissues and exhibit unique properties. How different PIEZOs transduce force, how their transduction mechanism varies, and how their unique properties match the functional needs of the tissues they are expressed in remain all-important unanswered questions. The nematode Caenorhabditis elegans has a single PIEZO ortholog (pezo-1) predicted to have twelve isoforms. These isoforms share many transmembrane domains but differ in those that distinguish PIEZO1 and PIEZO2 in mammals. We used transcriptional and translational reporters to show that putative promoter sequences immediately upstream of the start codon of long pezo-1 isoforms predominantly drive GFP expression in mesodermally derived tissues (such as muscle and glands). In contrast, sequences upstream of shorter pezo-1 isoforms resulted in GFP expression primarily in neurons. Putative promoters upstream of different isoforms drove GFP expression in different cells of the same organs of the digestive system. The observed unique pattern of complementary expression suggests that different isoforms could possess distinct functions within these organs. We used mutant analysis to show that pharyngeal muscles and glands require long pezo-1 isoforms to respond appropriately to the presence of food. The number of pezo-1 isoforms in C. elegans, their putative differential pattern of expression, and roles in experimentally tractable processes make this an attractive system to investigate the molecular basis for functional differences between members of the PIEZO family of mechanoreceptors.

Assessment of the impact of motor development on adaptation to learning

The article renders findings of the study of the development of school children’s reading skills and motor development (n=61). Pedagogical and psychological literature considers visual, auditory, and cognitive impairments as primary causes of difficulties in devel-oping reading skills. It is generalized an idea that all types of perception (visual, auditory, etc.) are of afferent-efferent nature: each of these sensory processes is based on its own motor components. Thepurposeof the research is to analyze the impact of student’s motor skills disorders on mastering reading skills; to find the root of the disorders using neuropsychological tests; to differentiate errors and identify effective correction methods. Researchmethodsareasfollows:O. Luria Neuropsychological Battery adapted to school children by Glozman J.; child dyslexia test by O. Korniev & O. Ishymova. Research results have been processed through mathematical statistics, i.e., Pearson correlation coefficient and point-biserial correlation coefficient. Results. It has been identified the most significant indices of the functioning of the motor system of a child, which influence the progress of mastering reading skills in two age groups of school children (aged 7-9 and 10-12). The research has found the most fundamental errors made by school children while per-forming tests that are a ground for basic neuropsycho-logical correction. Conclusions.It has been substantiated that reading is a multi-factor process, and helping a pupil under some reading difficulties. It cannot be lim-ited to monotonous methods. The research states that neuropsychological diagnostics contributes to finding poorly-developed elements, which affect a child’s learning, discovering errors, and developing an effective intervention plan. The first step of the correction should comprise the work with the child motor system, as proved by this research. It is noted that a sensorimotor correction based on M. Bernstein’s construction of movements may underly the program.Keyw ords: neuropsychological diagnostics, dyslexia, learning difficulties, sensorimotor correction. У статті представлені результати дослідження сформованості навичок читання школярів та їхнього рухового розвитку (n=61). У педагогічній та психологічній літературі основними причинами труднощів формування навичок читання найчастіше визначають зорові, слухові та когнітивні проблеми. Розглянуто черговий чинник у структурі розвитку дитини – руховий розвиток. Узагальнено думку, що всі види сприйняття (зорове, слухове тощо) мають аферентно-еферентний характер, в основі кожного з цих сенсорних процесів беруть участь свої рухові компоненти. Метою дослідження є визначення впливу рухових проблем школяра у оволодіння навичками читання; розуміння причини цих проблем за допомогою нейропсихологічних проб; диференціація помилок і визначення ефективних методів корекції. Методидослідження: класична батарея нейропсихологічних тестів О.Лурії, адаптована до дітей шкільного віку Ж.Глозман; методика діагностики дислексії у дітей О.Корнєва і О.Ішимової. Здійснено обробку результатів методами математичної статистики, а саме – кореляційний аналіз за Пірсоном та точково-бісеріальних коефіцієнтів кореляції. Результати.Визначено найбільш значущі показники роботи рухової системи дитини, які мають вплив на успішність оволодіння навичками читання у двох вікових групах школярів (7-9 та 10-12 років). З’ясовано найбільш значущі помилки при виконанні проб школярами, що є підставою для базових напрямків нейропсихологічної корекції. Висновки.Обґрунтовано, що читання – багаточинниковий процес і допомога дитині при труднощах з ним не може обмежуватися одноманітними методами. Констатовано, що нейропсихологічна діагностика допомагає встановити чинники, які є несформованими і впливають на навчання дитини, диференціювати помилки і побудувати ефективний корекційний маршрут. Першим кроком корекції має бути робота з руховою сферою дитини, що доведено нашим дослідженням. Зазначено, що основою програми може бути сенсомоторна корекція на базі теорії про побудову і біомеханіку рухів М.Бернштейна. Ключовіслова: нейропсихологічна діагностика, дислексія, труднощі навчання, сенсомоторна корекція.

Identification of a stereotypic molecular arrangement of endogenous glycine receptors at spinal cord synapses

Precise quantitative information about the molecular architecture of synapses is essential to understanding the functional specificity and downstream signaling processes at specific populations of synapses. Glycine receptors (GlyRs) are the primary fast inhibitory neurotransmitter receptors in the spinal cord and brainstem. These inhibitory glycinergic networks crucially regulate motor and sensory processes. Thus far the nanoscale organization of GlyRs underlying the different network specificities has not been defined. Here, we have quantitatively characterized the molecular arrangement and ultra-structure of glycinergic synapses in spinal cord tissue using quantitative super-resolution correlative light and electron microscopy (SR-CLEM). We show that endogenous GlyRs exhibit equal receptor-scaffold occupancy and constant packing densities of about 2000 GlyRs µm-2 at synapses across the spinal cord and throughout adulthood, even though ventral horn synapses have twice the total copy numbers, larger postsynaptic domains and more convoluted morphologies than dorsal horn synapses. We demonstrate that this stereotypic molecular arrangement is maintained at glycinergic synapses in the oscillator mouse model of the neuromotor disease hyperekplexia despite a decrease in synapse size, indicating that the molecular organization of GlyRs is preserved in this hypomorph. We thus conclude that the morphology and size of inhibitory postsynaptic specializations rather than differences in GlyR packing determine the postsynaptic strength of glycinergic neurotransmission in motor and sensory spinal cord networks.

Ebbinghaus Illusion

For 25 years, the web has been used for psychological research ( Krantz et al., 1997 ; Reips, 1997 ). While many areas of psychology have benefitted from the increased access to participants and other benefits of web-based research, one area of psychology has rarely taken advantage of the online format, that is, sensation and perception. Largely, sensation and perception research has not used the web because of the need for carefully calibrated equipment to successfully run their experiments. However, there may be classes of phenomena in our sensory processes that might be studied online where the equipment and stimuli vary. Suppose the critical feature of the stimulus is an abstraction of the physical stimulus that does not vary with different displays. In that case, these features can be successfully studied online, meaning that results from online studies will match those from controlled laboratories. This study will examine the Ebbinghaus illusion to illustrate the successful use of the web for perceptual research. The implications and some discussion of types of perceptual studies conducted on the web will be discussed.

Movement, Synchronization, and Partnering in Dance

In a neuroimaging study of tango dancers, the authors attempted to address two fundamental issues about dance: movement patterning (i.e., navigation of the legs in space) and synchronization of movement to the beat of music. The results of the study revealed the importance of the posterior parietal cortex to spatial navigation of movement and the cerebellum to synchronization to the beat. In a later two-person study of leading and following in dance, the author found that leaders accentuate motor processes, while followers accentuate sensory processes in their partnership. Dance is an interesting marriage of movement patterning, timing, and joint action.

Exploring Alterations in Sensory Pathways in Migraine

BackgroundMigraine is a neurological disorder characterized by intense, debilitating headaches, often coupled with nausea, vomiting and sensitivity to light and sound. Whilst changes in sensory processes during a migraine attack have been well-described, there is growing evidence that even between migraine attacks, sensory abilities are disrupted in migraine. Brain imaging studies have investigated altered coupling between areas of the descending pain modulatory pathway but coupling between somatosensory processing regions between migraine attacks has not been properly studied. The aim of this study was to determine if ongoing functional connectivity between visual, auditory, olfactory, gustatory and somatosensory cortices are altered during the interictal phase of migraine. MethodsTo explore the neural mechanisms underpinning interictal changes in sensory processing, we used functional magnetic resonance imaging to compare resting brain activity patterns and connectivity in migraineurs between migraine attacks (n= 32) and in healthy controls (n=71). Significant differences between groups were determined using two-sample random effects procedures (p<0.05, corrected for multiple comparisons, minimum cluster size 10 contiguous voxels, age and gender included as nuisance variables). ResultsIn the migraine group, increases in infra-slow oscillatory activity were detected in the right primary visual cortex (V1), secondary visual cortex (V2) and third visual complex (V3), and left V3. In addition, resting connectivity analysis revealed that migraineurs displayed significantly enhanced connectivity between V1 and V2 with other sensory cortices including the auditory, gustatory, motor and somatosensory cortices. ConclusionsThese data provide evidence for a dysfunctional sensory network in pain-free migraine patients which may be underlying altered sensory processing between migraine attacks.

Identification of a stereotypic molecular arrangement of glycine receptors at native spinal cord synapses

Precise quantitative information about the molecular architecture of synapses is essential to understanding the functional specificity and downstream signaling processes at specific populations of synapses. Glycine receptors (GlyRs) are the primary fast inhibitory neurotransmitter receptors in the spinal cord and brain stem. These inhibitory glycinergic networks crucially regulate motor and sensory processes. Thus far the nanoscale organization of GlyRs underlying the different network specificities has not been defined. Here, we have quantitatively characterized the molecular arrangement and ultra-structure of glycinergic synapses in native spinal cord tissue using quantitative super-resolution correlative light and electron microscopy (SR-CLEM). We show that GlyRs exhibit equal receptor-scaffold occupancy and constant absolute packing densities of about 2000 GlyRs µm−2 at synapses across the spinal cord and throughout adulthood, even though ventral horn synapses have twice the total copy numbers, larger postsynaptic domains and more convoluted morphologies than dorsal horn synapses. We demonstrate that this stereotypic molecular arrangement is maintained at glycinergic synapses in the oscillator mouse model of the neuromotor disease hyperekplexia despite a decrease in synapse size, indicating that the molecular organization of GlyRs is preserved in this hypomorph. We thus conclude that the morphology and size of inhibitory PSDs rather than differences in GlyR packing determine the postsynaptic strength of glycinergic neurotransmission in motor and sensory spinal cord networks.