Relación entre el estímulo musical y la producción de leche en madres con recién nacidos menores de 34 semanas en un centro de terapia intensiva: una experiencia de musicoterapia en Uruguay / Relationship between musical stimulation and milk production in mothers with newborns younger than 34 weeks old in an intensive care center: a music therapy experience in Uruguay / Relação entre o estímulo musical e a produção de leite materno em mães com recém nascidos menores de 34 semanas de vida assistidos no centro de terapia intensiva: experiencia de musicoterapia no Uruguai

Introducción: La relación entre producción de leche materna y la música ha sido reportada en diversas publicaciones científicas. No hay publicaciones en Uruguay que analicen esta relación. Este estudio fue realizado por el Instituto Universitario CEDIIAP junto a la Universidad ORT, el Banco de Leche Humana del Hospital Pereira Rossell (CHPR), de la Administración de los Servicios de Salud del Estado. Fue aprobado por el Comité de Ética del CHPR. Objetivo: evidenciar la relación entre el estímulo musical y la producción de leche de madres de recién nacidos pretérmino internados en Cuidados Intensivos del CHPR. Material y métodos: estudio cuasiexperimental, de corte longitudinal, prospectivo, diseño doble: intervención antes después y en paralelo (un grupo contra el otro) utilizando audición de canciones elegidas por las madres con andamiento modificado. Criterios de inclusión: cohorte de madres de recién nacidos ≤ 34 semanas de gestación, sin alimentación a pecho directo, medicación psiquiátrica o que afectara la producción de leche. Se analizó cortisol en saliva y volumen de leche. Como análisis multivariado final, se aplicó el modelo lineal general de medidas repetitivas. Resultados: el estudio se realizó entre marzo de 2017 y agosto de 2018 con 31 madres (15 intervención, 16 control). El grupo intervención presentó mayor producción láctea en los 2 primeros días y disminución del 57 % en niveles de cortisol frente al grupo control. Conclusiones: más allá de las limitaciones del trabajo, los resultados apuntan a que la musicoterapia podría colaborar en la disminución del estrés, el disfrute de la lactancia materna y, consecuentemente, en una mayor producción de leche.

Introduction: the relationship between breast milk production and music has been previously reported in several peer reviewed journals. There are no studies in Uruguay analyzing this relationship. The present study was performed by the CEDIIAP University Institute jointly with the ORT University, at the Pereira Rossell Hospital Human Milk Bank (CHPR) of the Administration of State Health Services (ASSE) in Montevideo. It has been approved by the CHPR's Ethics Committee. Objective: demonstrate the influence of musical stimulation on milk production of mothers with preterm newborns admitted in the CHPR Neonatology Intensive Care Unit. Material and Methods: longitudinal, prospective experimental study with double design: intervention before, simultaneous (one group against the other) and after the study. We used the music therapy technique of listening to songs chosen by the mothers and modified gait. Milk volume was quan- tified, and cortisol presence was analyzed in saliva. The General Linear Model of repetitive measures was applied. Inclusion criteria: cohort of mothers of newborns ≤ 34 weeks of gestation, without direct breastfeeding, psychiatric medication or affecting milk production. Saliva cortisol levels and milk volume were analyzed. As a final multivariate analysis, the General Linear Model of repetitive measures was applied. Results: the study was carried out from March 2017 till August 2018 with a total of 31 mothers (15 intervention, 16 control). Higher milk production in the first two days and a decrease of 57% in cortisol levels were observed in the intervention group compared to the control group. Conclusions: in spite of the limitations of this paper, our results suggest that music therapy can help to reduce the stress and increase the enjoyment of breastfeeding and consequently generate a higher milk production.

Introducion: a relação entre produção do leite materno e a música foi apontada com evidências científicas em vários jornais. Não existem publicações no Uruguai que analisem esta relação. Este estudo foi realizado pelo Instituto universitário CEDIIAP junto com a Universidade ORT, o Banco de Leite Humano do Hospital Pereira Rossell (CHPR) da Administração dos Serviços de Saúde do Estado. Foi aprovado pelo Comité de Ética do CHPR. Objetivo: evidenciar a relação entre o estímulo musical e a produção do leite de mães com recém nascidos prematuros internados na unidade de cuidados intensivos do CHPR. Material e metodo: estudo quase experimental de corte longitudinal, prospectivo com desenho duplo: intervenção antes, depois e em paralelo (um grupo contra o outro) utilizando a audição de canções escolhidas pelas mães e andamento modificado. Critérios de inclusão: coorte de mães de recém nascidos ≤ 34 semanas de gestação sem alimentação a peito direto, nem medicação psiquiátrica ou que afetara a produção de leite. Foi analisado o cortisol em saliva e o volumem de leite. Aplicouse o Modelo Linear General de medidas repetitivas como análise multivariado final. Resultados: o estudo foi realizado entre março 2017 e agosto 2018 com 31 mães (15 do grupo intervenção, 16 do grupo controle). Foi observada maior produção láctea no grupo de intervenção nos dois primeiros dias e diminuição de 57% nos níveis de cortisol em relação ao grupo controle. Conclusões: além das limitações do paper, os resultados apontam para que a musicoterapia poderia colaborar na diminuição do estresse, o desfrute da lactância materna e consequentemente poderiam resultar em uma maior produção de leite.

Binaural sound therapy for tinnitus treatment: A psychometric and neurophysiological evaluation.

INTRODUCTION: Tinnitus is an annoying buzz that manifests itself in many ways. In addition, it can provoke anxiety, stress, depression, and fatigue. The acoustic therapies have become the most commonly applied treatment for tinnitus, either self-administered or clinically prescribed. Binaural Sound Therapy (BST) and Music Therapy (MT) aim to reverse the neuroplasticity phenomenon related to tinnitus by adequately stimulating the auditory path-way. The goal of this research is to evaluate the feasibility of applying BST for tinnitus treatment by comparing its effect with MT effect. MATERIALS AND METHODS: 34 patients with tinnitus from 29 to 60 years were informed about the experimental procedure and consented their participation. Patients were divided into two groups: 1) MT and 2) BST. They applied their sound-based treatment for one hour every day along eight weeks. Each treatment was adjusted to Hearing Loss (HL) and tinnitus characteristics of each participant. To record EEG data, a bio-signal amplifier with sixteen EEG channels was used. The system recorded data at a sampling frequency of 256 Hz within a bandwidth between 0.1 and 100 Hz. RESULTS: The questionnaire-monitoring reported that MT increased tinnitus perception in 30% of the patients, and increased anxiety and stress in 8% of them. Regarding EEG-monitoring, major neural synchronicity over the frontal lobe was found after the treatment. In the case of BST reduced stress in 23% of patients. Additionally, BST reduced tinnitus perception similar to MT (15% of patients). With respect to EEG-monitoring, slightly major neural synchronicity over the right frontal lobe was found after the treatment. CONCLUSIONS: MT should be applied with caution since it could be worsening the tinnitus sufferer condition. On the other hand, BST is recommended for tinnitus sufferers who have side effects concerning stress but no anxiety.

Real-life dental examination elicits physiological responses different to visual and auditory dental-related stimuli.

BACKGROUND: Previous studies on dental anxiety have examined the psychophysiological responses evoked in dentally anxious subjects by dental-related stimuli, but not during a real-life dental examination, which was achieved in the present study. METHODS: The heart rate, skin conductance level, and heart rate variability of 25 subjects with dental anxiety and 25 healthy controls were examined. Anxiety was determined by the Modified Dental Anxiety Scale and the Dental Anxiety Scale-Revised. The psychophysiological reactions of the two groups were compared during exposure to dental-related pictures, dental-related sounds, and an actual examination in a dental surgery. RESULTS: All the dental-related stimuli provoked an increase in heart rate, i.e. visual stimuli (p<0.001; 95% CI 0.98-3.95 bpm), auditory stimuli (p<0.001; 95% CI 1.34-4.99 bpm), and a dental examination (p<0.001; 95% CI 1.26-5.39 bpm). Dental-related pictures provoked inferior skin conductance level changes compared to dental-related sounds and the dental examination (visual modality vs auditory p<0.001; 95% CI 0.039-0.152; visual modality vs examination p<0.001; 95% CI 0.083-0.275). Heart rate variability manifested in a complex pattern of responses to the dental examination. However, when exposed to all three dental-related stimuli presentation conditions, the heart rate (F = 0.352, p = 0.556), skin conductance level (F = 0.009, p = 0.926), and heart rate variability parameters of subjects with dental anxiety did not differ in comparison to the healthy controls. CONCLUSIONS: This pilot study represents an evaluation of psychophysiological reactions during a real-life dental examination compared to single modality stimuli, and shows that a real-life dental examination provokes an increase in heart rate, heart rate variability and skin conductance level. Additionally, autonomic responses did not differ between the experimental and control groups. The key issue for future studies is the effect of real-life situations on the physiological and psychological state of the subjects, which should be considered when planning new research and studied in depth.

Benefits in Alzheimer's Disease of Sensory and Multisensory Stimulation.

Alzheimer's disease (AD) is a serious neurodegenerative disease, which seriously affects the behavior, cognition, and memory of patients. Studies have shown that sensory stimulation can effectively improve the cognition and memory of AD patients, and its role in brain plasticity and neural regulation is initially revealed. This paper aims to review the effect of various sensory stimulation and multisensory stimulation for AD, and to explain the possible mechanism, so as to provide some new ideas for further research in this field. We searched the Web of Science and PubMed databases (from 2000 to October 27, 2020) for literature on the treatment of AD with sensory and multisensory stimulation, including music therapy, aromatherapy, rhythmic (e.g., visual or acoustic) stimulation, light therapy, multisensory stimulation, and virtual reality assisted therapy, then conducted a systematic analysis. Results show these sensory and multisensory stimulations can effectively ameliorate the pathology of AD, arouse memory, and improve cognition and behaviors. What's more, it can cause brain nerve oscillation, enhance brain plasticity, and regulate regional cerebral blood flow. Sensory and multisensory stimulation are very promising therapeutic methods, and they play an important role in the improvement and treatment of AD, but their potential mechanism and stimulation parameters need to be explored and improved.

Feasibility of a rhythmic auditory stimulation gait training program in community-dwelling adults after TBI: A case report.

BACKGROUND: Traumatic brain injury has multiple impacts on gait including decreased speed and increased gait variability. Rhythmic auditory stimulation (RAS) gait training uses the rhythm and timing structure of music to train and ultimately improve slow and variable walking patterns. OBJECTIVE: To describe the feasibility of RAS gait training in community-dwelling adults with traumatic brain injury (TBI). A secondary objective is to report changes in spatiotemporal gait parameters and clinical measures of balance and walking endurance. METHODS: Two individuals with a TBI participated in nine sessions of gait training with RAS over a 3-week period. At baseline, post-training and 3-week follow-up, spatiotemporal parameters of walking were analyzed at preferred pace, maximum pace and dual-task walking conditions. Secondary outcomes included the Community Balance and Mobility Scale and the 6-Minute Walk Test. Feasibility was assessed using reports of physical fatigue, adverse event reporting, and perceived satisfaction. RESULTS: Both participants completed all 9 planned intervention sessions. The sessions were well tolerated with no adverse events. Participant 1 and 2 exhibited different responses to the intervention in line with the therapeutic goals set with the therapist. Participant 1 exhibited improved speed and decreased gait variability. Participant 2 exhibited reduced gait speed but less fatigue during the 6MWT. CONCLUSIONS: RAS was found to be a safe and feasible gait intervention with the potential to improve some aspects of gait impairments related to gait speed, gait variability, dynamic balance and walking endurance. Further investigation including a pilot randomized controlled trial is warranted.

Implicit Semantic Processing of Linguistic and Non-linguistic Stimuli in Adults with Autism Spectrum Disorder.

While many individuals with autism spectrum disorder (ASD) experience difficulties with language processing, non-linguistic semantic processing may be intact. We examined neural responses to an implicit semantic priming task by comparing N400 responses-an event-related potential related to semantic processing-in response to semantically related or unrelated pairs of words or pictures. Adults with ASD showed larger N400 responses than typically developing adults for pictures, but no group differences occurred for words. However, we also observed complex modulations of N400 amplitude by age and by level of autistic traits. These results offer important implications for how groups are delineated and compared in autism research.

The Effect of Natural Ocean Sound Exposure and Ocean-Side Relaxation on Chronic Tinnitus Patients: A Pilot Study in Korea.

Sound therapy is a treatment modality for tinnitus patients by increasing the background neuronal activity in the auditory system and inducing relative alleviation of the tinnitus. This study was performed to evaluate the efficacy of natural ocean sound exposure and ocean-side relaxation in chronic tinnitus patients. We prospectively enrolled all 18 chronic tinnitus patients (≥6 months) from July to November 2018. All patients completed 90 hours of our programs. The improvement in their subjective tinnitus severity, moods, the quality of life, and sleep was serially assessed using several questionnaires at baseline, immediately, and 1 month after the program. Changes in serum stress hormone levels of the patients were also compared between the baseline and immediately after the program. Average total Tinnitus Handicap Questionnaire score and factor 2 (hearing difficulty related to tinnitus) score significantly improved over time (P = .024 and P = .002). Patient's serum cortisol and epinephrine level did not show significant decrease, and serum norepinephrine and serotonin level significantly increased immediately after our program (P < .001 and P < .001). Natural ocean sound exposure and ocean-side relaxation for short-term period has a potential efficacy on chronic tinnitus patients.

Instructed versus spontaneous entrainment of running cadence to music tempo.

Matching exercise behavior to musical beats has been shown to favorably affect repetitive endurance tasks. In this study, our aim was to explore the role of spontaneous versus instructed entrainment, focusing on self-paced exercise of healthy, recreational runners. For three 4-min running tasks, 33 recreational participants were either running in silence or with music; when running with music, either no instructions were given to entrain to the music, or participants were instructed to match their running cadence with the tempo of the music. The results indicated that less entrainment occurred when no instruction to match the exercise with the musical tempo was provided. In addition, similar to the condition without music, lower speeds and shorter step lengths were observed when runners were instructed to match their running behavior to the musical tempo when compared with the condition without such instruction. Our findings demonstrate the impact of instruction on running performance and stress the importance of intention to entrain running behavior to musical beats.

Avoiding Based on Shades of Gray: Generalization of Pain-Related Avoidance Behavior to Novel Contexts.

Avoidance behavior is protective, yet in the absence of genuine bodily threat, it may become disabling. Therefore, we investigated whether avoidance generalizes to novel safe contexts based on the similarity with the acquisition context. Healthy participants performed arm movements using a robotic arm to reach a target. Three trajectories (T1-3) led to the target. During acquisition, a painful stimulus could be partly/completely prevented by performing more effortful trajectories (ie, longer and more force needed), T2/T3, in the pain-avoidance context (eg, black background); in the yoked context (eg, white background), the same reinforcement schedule was applied irrespective of the chosen trajectories. Generalization of avoidance was tested in 2 novel contexts (eg, shades of gray backgrounds). We assessed self-reported pain-expectancy and pain-related fear for all trajectories, and avoidance behavior (ie, maximal deviation from T1). Results confirm that fear and expectancy ratings reflect the response-outcome contingencies and differential learning selectively generalized to the novel context resembling the original pain-avoidance context. Furthermore, a linear trend in avoidance behavior across contexts emerged, which is indicative of a generalization gradient. Participants avoided more in the context resembling the original pain-avoidance context than in the one resembling the yoked context, but this effect was not statistically significant. PERSPECTIVE: Perspective: We demonstrated acquisition of pain-related avoidance behavior in a within-subjects design, showing modulation of pain-related fear and pain-expectancy by context and providing limited evidence that avoidance selectively generalizes to novel, similar contexts. These results provide insight regarding the underlying mechanisms of the spreading of protective behavior in chronic pain patients.

Once an Avoider Always an Avoider? Return of Pain-Related Avoidance After Extinction With Response Prevention.

In exposure for chronic pain, avoidance is often forbidden (extinction with response prevention; RPE) to prevent misattributions of safety. Although exposure is an effective treatment, relapse is common. Little is known about the underlying mechanisms of return of pain-related avoidance. We hypothesized that pain-related avoidance would recover when becoming available again after RPE and after unexpected pain episodes ("reinstatement"), especially when restricting avoidance during RPE (compared to instructing not to use it). In an operant pain-related avoidance conditioning paradigm, healthy volunteers used a robotic arm to perform various arm reaching movements differing in pain-effort trade-off. During acquisition, participants learned to avoid pain by performing more effortful movements. During RPE they only performed the formerly pain-associated movement under extinction, and were either forbidden (Restricted group) or merely instructed (Instructed group) not to perform other movements. One day later, we tested spontaneous recovery and reinstatement of pain-related fear and avoidance with availability of all movements. Results showed that pain-related fear and avoidance re-emerge after RPE, though not to pretreatment levels. The reinstatement manipulation had no additional effect. No group differences were observed. We discuss findings in the context of learning processes in (chronic) pain disability and relapse prevention in chronic pain treatment. Perspective: Using experimental models of relapse, we investigated the return of pain-related avoidance behavior after extinction with response prevention. Findings are potentially informative for clinicians performing exposure treatment with chronic pain patients.

Cortical Microcircuit Mechanisms of Mismatch Negativity and Its Underlying Subcomponents.

In the neocortex, neuronal processing of sensory events is significantly influenced by context. For instance, responses in sensory cortices are suppressed to repetitive or redundant stimuli, a phenomenon termed "stimulus-specific adaptation" (SSA). However, in a context in which that same stimulus is novel, or deviates from expectations, neuronal responses are augmented. This augmentation is termed "deviance detection" (DD). This contextual modulation of neural responses is fundamental for how the brain efficiently processes the sensory world to guide immediate and future behaviors. Notably, context modulation is deficient in some neuropsychiatric disorders such as schizophrenia (SZ), as quantified by reduced "mismatch negativity" (MMN), an electroencephalography waveform reflecting a combination of SSA and DD in sensory cortex. Although the role of NMDA-receptor function and other neuromodulatory systems on MMN is established, the precise microcircuit mechanisms of MMN and its underlying components, SSA and DD, remain unknown. When coupled with animal models, the development of powerful precision neurotechnologies over the past decade carries significant promise for making new progress into understanding the neurobiology of MMN with previously unreachable spatial resolution. Currently, rodent models represent the best tool for mechanistic study due to the vast genetic tools available. While quantifying human-like MMN waveforms in rodents is not straightforward, the "oddball" paradigms used to study it in humans and its underlying subcomponents (SSA/DD) are highly translatable across species. Here we summarize efforts published so far, with a focus on cortically measured SSA and DD in animals to maintain relevance to the classically measured MMN, which has cortical origins. While mechanistic studies that measure and contrast both components are sparse, we synthesize a potential set of microcircuit mechanisms from the existing rodent, primate, and human literature. While MMN and its subcomponents likely reflect several mechanisms across multiple brain regions, understanding fundamental microcircuit mechanisms is an important step to understand MMN as a whole. We hypothesize that SSA reflects adaptations occurring at synapses along the sensory-thalamocortical pathways, while DD depends on both SSA inherited from afferent inputs and resulting disinhibition of non-adapted neurons arising from the distinct physiology and wiring properties of local interneuronal subpopulations and NMDA-receptor function.

Decomposing neural responses to melodic surprise in musicians and non-musicians: Evidence for a hierarchy of predictions in the auditory system.

Neural responses to auditory surprise are typically studied with highly unexpected, disruptive sounds. Consequently, little is known about auditory prediction in everyday contexts that are characterized by fine-grained, non-disruptive fluctuations of auditory surprise. To address this issue, we used IDyOM, a computational model of auditory expectation, to obtain continuous surprise estimates for a set of newly composed melodies. Our main goal was to assess whether the neural correlates of non-disruptive surprising sounds in a musical context are affected by musical expertise. Using magnetoencephalography (MEG), auditory responses were recorded from musicians and non-musicians while they listened to the melodies. Consistent with a previous study, the amplitude of the N1m component increased with higher levels of computationally estimated surprise. This effect, however, was not different between the two groups. Further analyses offered an explanation for this finding: Pitch interval size itself, rather than probabilistic prediction, was responsible for the modulation of the N1m, thus pointing to low-level sensory adaptation as the underlying mechanism. In turn, the formation of auditory regularities and proper probabilistic prediction were reflected in later components: The mismatch negativity (MMNm) and the P3am, respectively. Overall, our findings reveal a hierarchy of expectations in the auditory system and highlight the need to properly account for sensory adaptation in research addressing statistical learning.

Atypical Multisensory Integration and the Temporal Binding Window in Autism Spectrum Disorder.

The present study examined the relationship between multisensory integration and the temporal binding window (TBW) for multisensory processing in adults with Autism spectrum disorder (ASD). The ASD group was less likely than the typically developing group to perceive an illusory flash induced by multisensory integration during a sound-induced flash illusion (SIFI) task. Although both groups showed comparable TBWs during the multisensory temporal order judgment task, correlation analyses and Bayes factors provided moderate evidence that the reduced SIFI susceptibility was associated with the narrow TBW in the ASD group. These results suggest that the individuals with ASD exhibited atypical multisensory integration and that individual differences in the efficacy of this process might be affected by the temporal processing of multisensory information.

Assessing Autism Spectrum Disorder in Intellectually Able Adults with the Personality Assessment Inventory: Normative Data and a Novel Supplemental Indicator.

Differential diagnosis of autism spectrum disorder (ASD) among intellectually-able adults often presents a clinical challenge, particularly when individuals present in crisis without diagnostic history. The Personality Assessment Inventory (PAI) is a multiscale personality and psychopathology instrument utilized across clinical settings, but to date there are no published normative data for use of the PAI with adults with ASD. This study provides normative PAI data for adults diagnosed with ASD, with effect size comparisons to the PAI clinical standardization sample and an inpatient sample. Additionally, a discriminant function was developed and cross-validated for identification of ASD-like symptomatology in a clinical population, which demonstrates promise as a screening tool to aid in the identification of individuals in need of specialized ASD assessment.

Knowing what's coming: Anticipatory audio cues can mitigate motion sickness.

Being able to anticipate upcoming motion is known to potentially mitigate sickness resulting from provocative motion. We investigated whether auditory cues could increase anticipation and subsequently reduce motion sickness. Participants (N = 20) were exposed on a sled on a rail track to two 15-min conditions. Both were identical in terms of motion, being composed of the same repeated 9 m fore-aft displacements, with a semi-random timing of pauses and direction. The auditory cues were either 1) informative on the timing and direction of the upcoming motion, or 2) non-informative. Illness ratings were recorded at 1-min intervals using a 11-point scale. After exposure, average illness ratings were significantly lower for the condition that contained informative auditory cues, as compared to the condition without informative cues. This knowledge, i.e. that auditory signals can improve anticipation to motion, could be of importance in reducing carsickness in domains such as that of autonomous vehicles.

The impact of the verbal instruction and task characteristics on effect-based action control.

According to ideomotor theory, when people perform a movement and observe its subsequent effect, they acquire a bidirectional action-effect association. If at a later point they want to produce the effect, its anticipation activates and allows executing the corresponding action. In ideomotor induction tasks, several task characteristics determine whether participants use the experimentally induced action-effect associations to pre-activate the corresponding actions. Here, we assess the impact of the verbal instruction, the task relevance of the effect stimuli and the presentation of post-response effects on the expression of action-effect associations. The results show that an instruction stressing the stimulus-effect correspondence prompts participants to utilize the presented effects more than an instruction stressing the stimulus-response correspondence. Furthermore, the induced action-effect associations were only expressed when the effects were relevant for the task and when post-response effects were presented in the test phase. These findings show the importance of the particular task construction for the expression of the experimentally manipulated action-effect knowledge.

Estimation of frequency difference at which stream segregation precedes temporal integration as reflected by omission mismatch negativity.

Both stream segregation and temporal integration are considered important for auditory scene analysis in the brain. Several previous studies have indicated that stream segregation may precede temporal integration when both processes are required. In the present study, we utilized mismatch negativity (MMN)-which reflects automatic change detection-to systematically estimate the threshold of the frequency difference at which stream segregation occurs prior to temporal integration when these functions occur together during a state of inattention. Electroencephalography (EEG) data were recorded from 22 healthy Japanese men presented with six blocks of alternating high pure tones (high tones) and low pure tones (low tones). Only high tones were omitted with 5 % probability in all blocks. Our results indicated that stream segregation should cancel temporal integration of close sounds, as indicated by omission-MMN elicitation, when the frequency difference is 1000 Hz or larger.

Temporal order of musical keys and subjective estimates of time.

The aim of this study was to observe the influence of the temporal order of musical keys involved in sudden modulations, which implies compositional developments in clockwise and counterclockwise directions of the circle of fifths, on subjective time estimations. Seventy-five undergraduate students from Universidade de Ribeirão Preto participated in this experiment, which consisted of listening to a modulating musical stimulus and retrospectively reproducing the duration with the aid of a stopwatch. The results showed that reverse sudden tonal modulation in the counterclockwise direction or, for instance, the temporal order from the original key of A-major to the arrival at the destination key of C-major, elicited shorter time estimations than the clockwise direction or, for instance, the temporal order from original key of C-major to the arrival at the destination key of A-major. These data were interpreted using the Expected Development Fraction model that describes the development of expectations when an inter-key distance is traversed during a certain time interval. This expected development is longer than the perceived duration, leading to the underestimation of time.

Nicotine enhances auditory processing in healthy and normal-hearing young adult nonsmokers.

RATIONALE: Electrophysiological studies show that systemic nicotine narrows frequency receptive fields and increases gain in neural responses to characteristic frequency stimuli. We postulated that nicotine enhances related auditory processing in humans. OBJECTIVES: The main hypothesis was that nicotine improves auditory performance. A secondary hypothesis was that the degree of nicotine-induced improvement depends on the individual's baseline performance. METHODS: Young (18-27 years old), normal-hearing nonsmokers received nicotine (Nicorette gum, 6mg) or placebo gum in a single-blind, randomized, crossover design. Subjects performed four experiments involving tone-in-noise detection, temporal gap detection, spectral ripple discrimination, and selective auditory attention before and after treatment. The perceptual differences between posttreatment nicotine and placebo conditions were measured and analyzed as a function of the pre-treatment baseline performance. RESULTS: Nicotine significantly improved performance in the more difficult tasks of tone-in-noise detection and selective attention (effect size = - 0.3) but had no effect on relatively easier tasks of temporal gap detection and spectral ripple discrimination. The two tasks showing significant nicotine effects further showed no baseline-dependent improvement. CONCLUSIONS: Nicotine improves auditory performance in difficult listening situations. The present results support future investigation of nicotine effects in clinical populations with auditory processing deficits or reduced cholinergic activation.

Social network proximity predicts similar trajectories of psychological states: Evidence from multi-voxel spatiotemporal dynamics.

Homophily is a prevalent characteristic of human social networks: individuals tend to associate and bond with others who are similar to themselves with respect to physical traits and demographic attributes, such as age, gender, and ethnicity. Recent research using functional magnetic resonance imaging has demonstrated a positive relationship between individuals' real-world social network proximity (i.e., whether they are friends, friends-of-friends, or farther removed in social ties) and inter-subject correlation (ISC) in their time series of neural responses when viewing audiovisual movies. However, conventional ISC methods only capture information about similarity in the temporal evolution of region-averaged neural responses, and ignore information carried in fine-grained, spatially distributed response topographies. Here, we demonstrate that temporal trajectories of multi-voxel response patterns to naturalistic stimuli are exceptionally similar among friends and predictive of social network proximity, over and above the effects of response magnitude fluctuations. Furthermore, inter-subject similarity in the temporal trajectory of multi-voxel response patterns across distant points in time was particularly positively associated with individuals' proximity in their real-world social network. The fact that exceptional similarities among friends were most pronounced in long-range temporal fluctuations of response patterns located in multimodal cortical regions (e.g., regions of posterior parietal cortex) suggests that aspects of high-level processing during naturalistic stimulation may be particularly similar among friends. Given the localization of results, we speculate that socially close individuals may be particularly similar in endogenously driven shifts in how they distribute their attention (e.g., across the environment, within internal representations) over time. These results suggest that friends may experience exceptionally similar trajectories of psychological states when exposed to a common stimulus, and, more generally, that there are meaningful individual differences in the temporal evolution of multi-voxel response patterns during naturalistic stimulation.