Subsequent Sessions Research Articles

Chinese counseling trainees' trait and state mindfulness and client symptom outcome: A longitudinal examination with multilevel and random-intercept cross-lagged panel models.

This study aimed to explore how Chinese counseling trainees' trait and state mindfulness predicted their clients' symptom level over the course of therapy. A data set consisting of 6,888 sessions from 1,216 clients and their 211 master's level beginning therapist trainees in China was used, which included a measure of trainees' trait mindfulness at the beginning of their practicum and their state mindfulness and client-rated symptom distress level at the beginning of each of their therapy sessions. Multilevel modeling and random-intercept cross-lagged panel model results suggested that (a) at the trainee level, a trainee's trait mindfulness did not predict their average client symptom improvement over practicum; (b) at the session-to-session level, higher trainee state mindfulness before one session significantly predicted lower client distress before the next session, and higher client distress before one session did not predict trainee state mindfulness before the subsequent session. Findings suggested that it was the trainees' session-to-session state mindfulness, instead of their general trait mindfulness, that temporally led to greater client symptom reduction. Implications for clinical training were discussed. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Identifying who benefits most from supportive versus expressive techniques in psychotherapy for depression: Moderators of within- versus between-individual effects.

A recent randomized controlled trial (RCT) indicated that individuals with higher levels of attachment anxiety exhibited better treatment outcomes in supportive-expressive therapy (SET) relative to supportive therapy (ST). But to gain insight into within-patient therapeutic changes, a within-individual design is required. The present study contrasts previous findings based on theory-driven between-patient moderators with data-driven moderators of within-patient processes to investigate whether findings converge or diverge across these two approaches. We used data of 118 patients from the pilot and active phases of a recent RCT for patients with major depressive disorder, comparing ST with SET, a time-limited psychodynamic therapy. The predefined primary outcome measure was the Hamilton Rating Scale for Depression. Supportive versus expressive techniques were rated based on patients' end-of-session perspective. We compared previous findings based on moderators of between-patient effects with a data-driven approach for identifying moderators of within-patient effects of techniques on subsequent outcome. After false discovery rate corrections, of 10 preselected moderators, patients' attachment anxiety and domineering style remained significant. Of these, bootstrap resampling revealed significant differences between ST and SET techniques for the attachment anxiety moderator: Those with higher attachment anxiety benefited more from greater use of ST than SET techniques in a particular session, as evidenced by lower levels of symptoms at the subsequent session. Our within-individual findings diverge from previously published between-individual analyses. This proof-of-concept study demonstrates the importance of complementing between-individuals with within-individual analyses to achieve better understanding of who benefits most from specific treatment techniques. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Transcranial focused ultrasound stimulation in the infralimbic cortex facilitates extinction of conditioned fear in rats

Transcranial focused ultrasound (tFUS) neuromodulation emerges as a promising non-invasive approach for improving neurological conditions. Extinction of conditioned fear has served as a prime model for exposure-based therapies for anxiety disorders. We investigated whether tFUS stimulation to a critical brain area, the infralimbic subdivision of the prefrontal cortex (IL), could facilitate fear extinction using rats. In a series of experiments, tFUS was delivered to the IL of a freely-moving rat and compared to sham stimulation (tFUS vs. SHAM). Initially, Fos expression in the IL was measured shortly after the stimulation. The results show that Fos expression was significantly increased in the IL but not in the neighboring regions compared to SHAM. Subsequently, two groups of rats were subjected to fear conditioning, extinction, and retention while receiving stimulation during the extinction. Rats in the tFUS group froze significantly less than SHAM during both extinction and retention tests. Importantly, the reduced freezing in the tFUS group was not attributable to non-specific effect such as auditory noise, as both groups demonstrated a similar level of locomotive activity in an open field regardless of the stimulation condition. Finally, we replicated the procedure with a shortened conditioning-to-extinction interval (15 min) to induce immediate extinction deficit. The tFUS group showed a facilitated reduction in freezing during the extinction, which persisted in the subsequent retention session compared to SHAM. In summary, the current findings suggest that tFUS stimulation in the IL facilitates fear extinction, offering a potential therapeutic regimen for fear-related psychiatric disorders.

Complete Remission of Drug-Induced Acute Dizziness Using Eight Constitution Acupuncture and the Barbecue Maneuver: A Case Report

Dizziness, often symptomatic of underlying conditions, presents management challenges especially when dealing with drug-induced vestibular disorders. Complementary therapies like acupuncture, specifically, Eight Constitution Acupuncture (ECA), offers a potential alternative to other management therapies. A 74-year-old female, experiencing sudden dizziness from medication for back pain, underwent a detailed examination, constitutional diagnosis, and targeted acupuncture involving 26 insertions over 4 sessions. The treatment for dizziness, which focused on constitutional differences, integrated ECA and the barbecue maneuver which resulted in significant efficacy. A 50% reduction in the Numeric Rating Scale score from 10 to 5 was observed after the 1<sup>st</sup> session. Subsequent sessions of ECA combined with the barbecue maneuver significantly reduced symptoms of dizziness and ultimately alleviated symptoms. This case underscored the potential of ECA when combined with the application of the barbecue maneuver in treating drug-induced vestibular disorders and residual benign paroxysmal positional vertigo. The ECA's constitutional approach allows for precise targeting and symptom resolution, and integrating the principles of Traditional Asian Medicine with biological mechanisms. Notably, this is the 1<sup>st</sup> case report of the efficacy of ECA and the barbecue maneuver in addressing drug-induced vestibular disorders. A holistic approach, considering constitutional differences, can offer insights and tailored solutions to present a promising avenue for patients experiencing such conditions. Rigorous research studies are essential to validate these findings.

Modeling the repetitions-in-reserve-velocity relationship: a valid method for resistance training monitoring and prescription, and fatigue management.

Establishing a relationship between repetitions left in reserve and the mean absolute velocity (RIR-velocity relationship) during resistance training (RT) could allow for objective monitoring, prescription, and real-time adjustment of the training load and set-volume. Therefore, we examined the goodness of fit and prediction accuracy of general and individual RIR-velocity relationships in the free-weight back squat exercise. The effects of sex, training status and history, as well as personality traits, on the goodness of fit and the accuracy of these relationships were also investigated. Forty-six resistance-trained people (15 females and 31 males) performed a one-repetition maximum (1RM) test, and two repetitions to failure (RTF) tests 72 h apart. We found greater goodness of fit of individual RIR-velocity relationships compared to general RIR-velocity relationships. Individual, but not general RIR-velocity relationships established in the first testing session yielded acceptable prediction accuracy of RIR (mean error <2 repetitions) in the subsequent testing session, regardless of the load used. Similar results were obtained when both general and individual RIR-velocity relationships were averaged across the loads, suggesting that a single RIR-velocity relationship covering a range of loads can be used instead of traditional RT methods, potentially allowing for better fatigue management and more efficient adaptation.

Treatment overshadowing as a reason for patient non-attendance at pelvic-floor muscle training sessions

This study explores the reasons for patient non-attendance at scheduled pelvic floor muscle training (PFMT) sessions. Although only limited research has been conducted on this topic, it is crucial to understand its implications for resources, non-attendance rates and the significance of the underlying reasons. Forty-four women were selected at random from patients with pelvic floor dysfunction who had not attended a scheduled PFMT session within the past 12 months. Semi-structured telephone interviews were used to gain information about the reasons for patient non-attendance, and three were identified by qualitative analysis. Life events and comorbidities, as well as administrative issues (e.g. not receiving the appointment letter) were found to be important. A new issue, termed “treatment overshadowing”, was also identified, i.e. the manner with which one treatment option was introduced by a referring medical practitioner interfered with the consideration of the other options. The latter has potential for further exploration and action to improve non-attendance rates at subsequent PFMT sessions.

How many sessions of quantum key distribution are allowed from the first launch to the next restart of the system?

Quantum cryptography systems are systems for extending the initial start key, which is required at the start of the system, to ensure information-theoretic authentication of messages in the classical communication channel. In subsequent sessions, a quantum key is generated, part of which is used for authentication in subsequent sessions. There is a fundamental question for quantum cryptography—how many sessions of quantum key distribution (QKD) can be held until the cryptographic properties of the quantum keys are reached a critical level, after which they can no longer be used for cryptographic purposes, and a new restart of the quantum cryptography system will be required. An explicit expression of the allowable number of sessions of quantum key distribution is obtained. It is shown that for the real parameters of the system, it is possible for the system to work almost indefinitely until the next initialization.

Control-FREEC viewer: a tool for the visualization and exploration of copy number variation data

BackgroundCopy number alterations (CNAs) are genetic changes commonly found in cancer that involve different regions of the genome and impact cancer progression by affecting gene expression and genomic stability. Computational techniques can analyze copy number data obtained from high-throughput sequencing platforms, and various tools visualize and analyze CNAs in cancer genomes, providing insights into genetic mechanisms driving cancer development and progression. However, tools for visualizing copy number data in cancer research have some limitations. In fact, they can be complex to use and require expertise in bioinformatics or computational biology. While copy number data analysis and visualization provide insights into cancer biology, interpreting results can be challenging, and there may be multiple explanations for observed patterns of copy number alterations.ResultsWe created Control-FREEC Viewer, a tool that facilitates effective visualization and exploration of copy number data. With Control-FREEC Viewer, experimental data can be easily loaded by the user. After choosing the reference genome, copy number data are displayed in whole genome or single chromosome view. Gain or loss on a specific gene can be found and visualized on each chromosome. Analysis parameters for subsequent sessions can be stored and images can be exported in raster and vector formats.ConclusionsControl-FREEC Viewer enables users to import and visualize data analyzed by the Control-FREEC tool, as well as by other tools sharing a similar tabular output, providing a comprehensive and intuitive graphical user interface for data visualization.

Progressive Pain Response in Idiopathic Clubfoot Children Undergoing Ponseti Casting: A Prospective Evaluation in 34 Feet.

Investigations of pain and physiologic responses response during Ponseti casting are in the preliminary stage. This short-term study aims to quantify pain responses and to note the variations, if any, during subsequent casting sessions. In this prospective study, the pain parameters were evaluated in 34 clubfeet. Video recording of each casting session was performed 1 minute before casting, during casting, and after 1 minute of casting. The videos were scored objectively using Neonatal Infant Pain Score (NIPS). Heart rate (HR) and oxygen saturation were recorded by using a pulse oximeter. There was progressive increase in pain response until, at the last casting session, it was recorded as NIPS 4 (interquartile range, 1) (P = .02479). Before, during, and after casting, HR rose significantly in succeeding sessions. The mean HR during the first cast session was 175.5 ± 27.2/min, which increased to a mean of 197.3 ± 18.9/min (P = .000282). For the third parameter (oxygen saturation), no differences were observed between the first and last casting sessions. There was moderate pain response during Ponseti casting sessions as demonstrated by the NIPS. It rose significantly toward the last cast. The clubfoot child showed an exaggerated heart rate in succeeding casting sessions. No variations were noticed for oxygen saturation.

Penerapan Metode Brainwriting terhadap Gambar Berantai pada Keterampilan Menulis Puisi Kelas VIII-A SMP Laboratorium UM

This study explores the implementation of brainwriting to chain images as a method to enhance poetry writing skills. Employing a descriptive qualitative approach, the research applies the STAR method (Situation, Task, Action, and Result) to analyze the effectiveness of this approach. Data collection methods include observation, questionnaire administration, testing, and document analysis. The study focuses on students in class VIII-A of UM Laboratory Middle School, comprising 32 students, with 14 male and 18 female participants. By utilizing the brainwriting technique to generate and connect ideas for image chaining, students' engagement and motivation in learning are expected to increase. The subsequent discussion sessions following brainwriting activities facilitate the exchange of perspectives and emotions among students regarding the chained images, fostering empathy and deeper understanding. The collaborative nature of the padlet platform enhances communication and interaction among students, creating a conducive environment for exploring and expressing ideas. Through this process, students not only improve their poetry writing skills but also develop their ability to interpret and convey emotions through visual imagery. Overall, the findings suggest that incorporating brainwriting into poetry writing sessions can be an effective strategy to stimulate creativity and enhance students' learning experience in poetry composition.

A ‘training of trainers’ programme for operational research: increasing capacity remotely

ABSTRACT Background Operational research (OR) is a process to improve health system capacity by evaluating interventions to improve health delivery and outcomes. The World Health Organization (WHO) Structured Operational Research Training Initiative (SORT-IT) programme promotes how OR contributes to improved health care delivery and health outcomes. A partnership project between the International Institute of Primary Health Care (IPHCE) in Ethiopia and The University of Queensland (UQ) in Australia modified the SORT-IT programme to deliver a hybrid Training of Trainers programme and improve OR capacity. Objective This study was performed to develop and evaluate the effectiveness of Train-the Trainers approach in building capability to expand the capacity of the IPHCE to deliver the SORT-IT programme. Methods Recruitment of participants and training were aligned with the principles of the SORT-IT programme. Training was face-to-face for the first session with subsequent training sessions delivered via Zoom over a 13-week period. Participants were required to complete all activities in line with SORT-IT deliverables. Slide decks supporting the SORT-IT training videos were developed and adapted to the Ethiopian context. Results Participants had diverse experience from programme directors to research officers. All training sessions were recorded and available for participants to watch and review when required. All participants completed OR protocols to the draft stage. Course evaluation revealed participants found the content and format of the training useful, pertinent, and interesting. Conclusion A hybrid model (face-to-face and video platform) for OR training was implemented. Managing contextual challenges such as information technology were managed easily by programme staff. Translating course requirements at a management level proved challenging with data collection for the protocols but provided insight into potential future challenges. This OR Training of Trainers course demonstrated that sharing of skills and knowledge can occur through a hybrid delivery model and contribute to developing capacity.

Effect of applied cadence in repeated sprint cycling on muscle characteristics

PurposeThis study aimed to investigate physiological responses, muscle–tendon unit properties of the quadriceps muscle, and mechanical performance after repeated sprint cycling at optimal and 70% of optimal cadence.MethodsTwenty recreational cyclists performed as first sprint performance cycling test and during subsequent sessions two repeated sprint cycling protocols at optimal and 70% of optimal cadence, in random order. The muscle–tendon unit outcome measures on the dominant leg included muscle thickness, fascicle length (Lf), pennation angle (θp), and stiffness for the rectus femoris (RF), vastus lateralis (VL), and vastus medialis muscle (VM) at baseline, immediately after repeated sprint cycling, and 1-h post-exercise.ResultsThe results showed an increase in muscle thickness and θp in RF, VL, and VM for both cadences from baseline to immediately after exercise. The Lf decreased in RF (both cadences), while stiffness decreased in RF, VL, and VM at optimal cadence, and in VL at 70% of optimal cadence from baseline to immediately after exercise.ConclusionThe present study revealed that the alterations in muscle characteristics were more marked after repeated sprint cycling at optimal cadence compared with a lower cadence most likely as a result of higher load on the muscle–tendon unit at optimal cadence.

Domain Incremental Object Detection Based on Feature Space Topology Preserving Strategy

Object detection with the capacity to incrementally adapt to new domains is a crucial yet relatively under-explored research topic. The <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">catastrophic forgetting</i> problem presents a significant challenge to achieve this goal, where the model’s performance improves quickly in new conditions but deteriorates sharply in old ones after several incremental learning sessions. Drawing on recent discoveries in visual memories of the human brain, we introduce the Topology-Preserving Domain Incremental Object Detection (TP-DIOD) approach, which aims to address the catastrophic forgetting problem by extracting the topological structure of the feature space learned by the Convolutional Neural Network (CNN) model and preserving this topology during the subsequent incremental learning sessions. Specifically, we model the feature space topology using the self-organizing map (SOM) and construct an anchor image set based on the centroid vectors of the SOM nodes to memorize the feature space topology. We then develop the anchor loss function to penalize the topological changes of the feature space during the subsequent incremental learning sessions. Experimental evaluations on two sets of datasets demonstrate the effectiveness of the proposed TP-DIOD method in mitigating the catastrophic forgetting problem and achieving high accuracy on both old and new domain datasets.

A Siamese Convolutional Neural Network for Identifying Mild Traumatic Brain Injury and Predicting Recovery.

Timely diagnosis of mild traumatic brain injury (mTBI) remains challenging due to the rapid recovery of acute symptoms and the absence of evidence of injury in static neuroimaging scans. Furthermore, while longitudinal tracking of mTBI is essential in understanding how the diseases progresses/regresses over time for enhancing personalized patient care, a standardized approach for this purpose is not yet available. Recent functional neuroimaging studies have provided evidence of brain function alterations following mTBI, suggesting mTBI-detection models can be built based on these changes. Most of these models, however, rely on manual feature engineering, but the optimal set of features for detecting mTBI may be unknown. Data-driven approaches, on the other hand, may uncover hidden relationships in an automated manner, making them suitable for the problem of mTBI detection. This paper presents a data-driven framework based on Siamese Convolutional Neural Network (SCNN) to detect mTBI and to monitor the recovery state from mTBI over time. The proposed framework is tested on the cortical images of Thy1-GCaMP6s mice, obtained via widefield calcium imaging, acquired in a longitudinal study. Results show that the proposed model achieves a classification accuracy of 96.5%. To track the state of the injured brain over time, a reference distance map is constructed, which together with the SCNN model, are employed to assess the recovery state in subsequent sessions after injury, revealing that the recovery progress varies among subjects. The promising results of this work suggest that a similar approach could be potentially applicable for monitoring recovery from mTBI, in humans.

Universal scoring system for assessing speech function in patients with cleft palate at the stages of surgical treatment

To develop a universal system for assessing the speech function in patients with congenital palatal cleft in the postoperative period. A universal system for assessing the speech function for patients with a palatal cleft can be applied both after the primary operation of uranoplasty and for patients diagnosed with velopharyngeal insufficiency (VPI). The patient's speech is assessed according to the following criteria: defects in the pronunciation of consonants by place of articulation: labial, labiodental, lingual-dental, lingual-palatal, lingual-alveolar; speech breathing; tongue position; directed air stream; voicing disorders; The patient's is also evaluated for the following findings: hypernasality (reflected speech); hypernasality (spontaneous speech); hyponasality; pharyngeal reflex; audible nasal emission/turbulence; facial grimaces; speech intelligibility. The speech therapy and dental assessments are added to obtain a value characterizing the patient's condition: from 0 to 10 scoring indicates than only speech therapy correction is needed; from 11 to 18 - the decision on the necessity of surgical treatment is made by the surgeon together with the speech therapist, from 18 to 25 - surgical treatment is necessary with subsequent sessions with a speech therapist. With the help of this questionnaire, the operating surgeon can more accurately and objectively assess in dynamics the result of the surgical treatment, regardless of the results of speech therapy treatment in the postoperative period. The creation of this scoring system for speech assessment is aimed at objectivizing the results of uranoplasty and speech-improving operations. It allows the surgeon to compare the effectiveness of different surgical methods. The universal scoring system for assessing the state of speech function can be applied in the diagnosis of a patient with a palatal cleft both after the primary operation on the palate and after corrective surgical interventions. It allows monitoring progress and identifying dynamics in surgical and speech therapy treatment.

Therapist and client perceptions of the working alliance: Codevelopment, linear growth, variability, and client functioning.

Using longitudinal client and therapist working alliance ratings, previous research examined how alliance: average value, linear growth, variability, stability (autocorrelation), and partner responsiveness were associated with client outcome. However, no research simultaneously examined all of these dimensions. Omitting important variables in analyses could lead to overestimation of related effects. Therefore, the purpose of this study was to examine these effects simultaneously. Therapists (N = 45) and clients (N = 236) rated alliance after every session (N = 10,720) and clients completed a measure of psychological distress after every eighth session. We used dynamic structure equation modeling to model longitudinal ratings using the longitudinal actor-partner interaction and location-scale models. Across sessions, there were significant linear growth and significant variability in client and therapist alliance ratings. The variability indicates multiple "V" patterns, which have been associated with alliance ruptures. Both actor effects were significant, showing session-to-session stability for client and therapist alliance. In addition, client-partner effect was significant, indicating higher-than-usual client alliance in a session predicting an increase in therapist alliance in the subsequent session. Growth in neither client-rated nor therapist-rated working alliances was significantly associated with client improvement. Lower variabilities (fewer fluctuations) in both client- and therapist-rated working alliances were associated with better outcomes. Higher therapist-actor and partner effects were associated with client improvement, but client-actor and partner effects were not associated with client improvement. Average working alliances were not associated with client improvement. Implications for practice and research were discussed. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Ab. No. 122 Functional Restoration Approach in the Management of Complex Regional Pain Syndrome (Crps) Caused By Onychomycosis: A Case Report

Introduction: The objective of this case report is to highlight the importance of incorporating functional restoration approach in the physiotherapy management of CRPS. The significant pain and disability associated with CRPS is not only biomedically faceted but frequently encompasses psychosocial aspects too. Physiotherapy management should address both these aspects. The functional restoration approach emphasizes gradual progression, starting with pre-sensorimotor cortices activation, then advancing to functional tasks. Methods: This is a case review of a 61 year old man with history of Onychomycosis presenting with left shoulder, wrist and hand stiffness and pain 6 months post the infection. Patient also presented with fear of movement and was reported to have had not used the arm functionally for daily activities since the onset of the infection. Patient is a k/c/o intentional tremors since 25 years. The functional restoration approach included patient education, desensitization using kinetic sand, followed by movement with Mulligan’s technique and graded functional activity by perpetual training over subsequent sessions. Pre and post assessments after a 3-week intervention included Kinesiophobia, Function, Pain, ROM, and grip strength. Additionally, the Archimedes spiral test was used to gauge tremor severity as a secondary outcome. Results: Post-intervention, positive changes were observed in outcome measures: a 16% decrease in Tampa Scale of Kinesiophobia, 10% improvement in Michigan Hand Outcome, 7% in grip strength, and 7% and 8% in wrist and shoulder ROM, respectively. The Archimedes spiral test also showed a notable improvement. Conclusion: The approach demonstrated improvement in Function, pain, and Kinesiophobia, with notable changes in range of motion, grip strength, and tremors as well. Implication: Functional restoration approach is a comprehensive method of managing CRPS since it addresses the syndrome’s multifaceted nature. Simultaneous assessment of biopsychosocial components aids in tracking progress and predicting better outcomes.

MAINTAINING WALKING THROUGH WALK ON!: A COMMUNITY-BASED WALKING PROGRAM FOR OLDER ADULTS

Abstract The NIA-funded LIFE study showed that a walking-based intervention prevents mobility disability, even in those with compromised walking ability. However, increases in activity were not maintained following cessation of the intervention, suggesting novel approaches and accessible opportunities are needed to provide continued support for this population to maintain increased walking. We previously reported high feasibility and acceptability from a pilot of a supervised, group-based, and fee-for-service walking program (Walk On!) for adults with mobility challenges. The program focuses on walking stamina, and takes place two days/week for 12 weeks. Walk On! was offered for a total of ten consecutive sessions from late 2017 until March 2020 at a local church. The majority of attendees were &amp;gt;75 years (71%), female (65%), and had low levels of physical function (usual gait speed=0.79±0.16; 31% used an assistive device). Of the 49 unique (first-time) attendees who registered for Walk On!, only 18 (37%) did not re-register for at least one subsequent session. Thus, 63% (n=31) registered for at least 2 sessions, 51% (n=25) for at least 3 sessions, 20 (41%) for at least 4 sessions, and 15 (31%) for at least 5 of the 10 sessions. Mean attendance at scheduled group walking days for all attendees was 77%±21% for all attendees and did not decrease substantially for those attending multiple sessions. The safe, social, and accessible community-based Walk On! program may be one approach to sustain walking for older adults with mobility challenges. Future research will focus on measuring individual characteristics associated with maintenance.

The effects of summarization and factual retrieval practice on text comprehension and text retention in elementary education.

When reading a text in school, the goal is both text comprehension and text retention. We examined the effects of the learning strategies summarization and factual retrieval practice on third- and fourth-grade pupils' text comprehension and retention of factual knowledge from a text, using restudy as a control condition. The experiment was conducted in an authentic classroom setting, with teachers executing the experiment using original course materials. In 2016, 57 regular third- and fourth-grade pupils (M = 9.04 years old) read three different texts, and each applied three different learning strategies (summarization, retrieval practice and restudy, which were counterbalanced across texts) in subsequent practice sessions. After a 2-week delay, a final test was administered. The learning strategy summarization had a larger positive effect on text comprehension than factual retrieval practice, but had a similar effect compared to restudy. The learning strategy factual retrieval practice had a larger positive effect on text retention than both summarization and restudy. Implications for educational practice are discussed. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Dynamics of space coding by mouse hippocampal CA1 field neurons in a free navigation task in different environments

The development of persistent cognitive adaptations in neurons is a key area of focus in contemporary neuroscience. A significant illustration of such adaptations occurs through spatial specializations in place cells with one or more receptive fields that are sensitive to spatial cues (place fields) [1]. In prior research, we extensively examined the dynamics of place field formation in granular layer neurons of the CA1 field in the hippocampus of mice during arbitrary free navigation in a circular track [2]. As the primary factor for maintaining stability in the spatial specialization of place cells, we have introduced dynamic selectivity. This approach enables us to monitor the latency of each place field’s formation and the selectivity dynamics of place cells to their respective fields throughout one or multiple shooting sessions. However, in one-dimensional settings, like the circular track referenced previously, place fields can demonstrate direction-specificity with regards to animal movement [3]. This factor considerably complicates the analysis for arbitrary movement trajectories of animals. In this study, additional experiments were conducted to capture the neural activity of mice in two-dimensional environments. The experiments were conducted in both a rectangular field with objects and a circular arena with a varying number of obstacles. In this paper, we conduct a comparative analysis to examine the critical parameters governing the development of spatial specializations in a one-dimensional circle track and two-dimensional arenas. These parameters include specialization latency, average dynamic selectivity, initial increase in selectivity, and the proportion of “immediate” place fields that remain stable from the first animal visit. The study discovered that the mean selectivity of the place fields escalated in each session, with higher rates observed in subsequent sessions versus the initial session in a novel setting. Additionally, there was a significant occurrence of “immediate” place fields, representing 11% of all place fields in the rounded arena with obstacles, and 25% of all place fields in the circular track. Additionally, a population analysis of neural activity was performed on the first session in a circular track and a round arena with obstacles. Using Laplace eigenmaps for the dimension reduction of population vectors, the trajectory of animals was reconstructed, and the accuracy of this reconstruction agreed with the average dynamic selectivity for each animal included in the analysis. Thus, dynamic selectivity was verified as a measure of the spatial coding quality of the entire registered population of neurons.