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1.
Neuroscience ; 556: 66-72, 2024 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-39103044

RESUMEN

When performing synchronous hand and foot movements, the way the limbs are synchronized differs depending on the mode of control. When performed in a reaction time (RT) paradigm (reactive control), EMG onsets become synchronized resulting in asynchronous displacement onset. However, when the same movement is performed as an anticipation-timing task (predictive control), displacement onset is synchronized by unconsciously introducing a small delay between EMG onsets. The present experiment investigated the reprogramming costs associated with switching between predictive and reaction control modes. Participants (N = 12, 6F) were asked to simultaneously lift their right heel and right hand in an anticipation-timing task when a rotating clock hand reached a specified target. On some trials, an auditory stimulus was presented either 250 ms or 500 ms before the target and participants were instructed to execute the synchronous movement as quickly as possible after the signal (i.e., switch to reactive mode). Results showed that when the auditory stimulus was delivered 250 ms before the target, participants were unable to switch to a reactive control mode but did switch when the auditory stimulus was presented 500 ms before the target. As expected, the RT on switch trials was substantially longer (∼230 ms) than a simple RT control condition but was also significantly longer (∼130 ms) than a choice RT control condition. These results indicate that switching between control modes for a task involving the same musculature incurs reprogramming costs that are even greater than the time required to program the response de novo.


Asunto(s)
Electromiografía , Desempeño Psicomotor , Tiempo de Reacción , Humanos , Masculino , Femenino , Tiempo de Reacción/fisiología , Desempeño Psicomotor/fisiología , Adulto Joven , Adulto , Estimulación Acústica/métodos , Movimiento/fisiología , Músculo Esquelético/fisiología , Mano/fisiología , Anticipación Psicológica/fisiología
2.
Hum Mov Sci ; 96: 103255, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39089055

RESUMEN

Individuals with bilateral spastic cerebral palsy (BSCP) reportedly has problems with anticipatory postural adjustments (APAs) while standing. However, the use of coactivation strategy in APAs in individuals with BSCP has conflicting evidence. Hence, this study aimed to investigate postural muscle activities in BSCP during unilateral arm flexion task in which postural perturbations occur in the sagittal, frontal, and horizontal planes. We included 10 individuals with BSCP with level II on the Gross Motor Function Classification System (BSCP group) and 10 individuals without disability (control group). The participants stood on a force platform and rapidly flexed a shoulder from 0° to 90° at their own timing. Surface electromyograms were recorded from the rectus femoris, medial hamstring, tibialis anterior, and medial gastrocnemius. The control group showed a mixture of anticipatory activation and inhibition of postural muscles, whereas the BSCP group predominantly exhibited anticipatory activation with slight anticipatory inhibition. Compared with the control group, the BSCP group tended to activate the ipsilateral and contralateral postural muscles and the agonist-antagonist muscle pairs. The BSCP group had a larger disturbance in postural equilibrium, quantified by the peak displacement of center of pressure during the unilateral arm flexion, than those without disability. Individuals with BSCP may use coactivation strategy, mainly the anticipatory activation of postural muscle activity, during a task that requires a selective postural muscle activity to maintain stable posture.


Asunto(s)
Brazo , Parálisis Cerebral , Electromiografía , Músculo Esquelético , Equilibrio Postural , Humanos , Parálisis Cerebral/fisiopatología , Masculino , Femenino , Músculo Esquelético/fisiopatología , Equilibrio Postural/fisiología , Brazo/fisiopatología , Adulto Joven , Anticipación Psicológica/fisiología , Adulto , Posición de Pie , Movimiento/fisiología , Fenómenos Biomecánicos/fisiología , Postura/fisiología , Adolescente
3.
Brain Res Bull ; 216: 111048, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39128676

RESUMEN

BACKGROUND: Imagine if our brains could unconsciously predict future events. This study explores this concept, presenting evidence for an inherent 'foreseeing' ability, termed anomalous cognition (AC). We introduce a new experimentally verifiable approach to explain anomalous information anticipation (AIA), a type of AC, based on an innovative, quantum-like model of implicit learning, grounded in Nonlocal Plasticity Theory (NPT). METHODS: Our research involved 203 participants using methods such as continuous flash suppression, random dot motion, and advanced 3D EEG neuroimaging, along with IBM quantum random event generators for precise measurements across 144 trials. These trials tested contingencies between undetectable sensory stimuli and dot movements, focusing on participants' prediction abilities. The design conditions were strictly experimental, violating fundamental classical learning principles, particularly reflex conditioning. If these principles were immutable, their violation would prevent any systematic behavioral changes, resulting in random responses. This violation was implemented through two quantum physics concepts: the mathematical principle of nonlocality and entanglement. RESULTS: Despite the sensory stimulus being inaccessible, our results showed a significant prediction between the contingencies and an increase in AIA accuracy, with explained variances between 25 % and 48 %. EEG findings supported this, showing a positive link between brain activity in specific regions and AIA success. Electrochemical activations were detected in the posterior occipital cortex, the intraparietal sulcus, and the medial temporal gyri. AIA hits exceeded the threshold value corresponding to one standard deviation above the expected mean, showing moderate effect sizes in the experimental group (Cohen's d = 0.461). Analyzing the learning curve using the derivation technique, we identified the acceleration point of the wave function, indicating systematic implicit learning. This result showed that from repetition 63 onwards, AIA hits increased significantly. CONCLUSIONS: The results suggest that, despite violating fundamental classical learning principles, cognitive processes produced changes in participants' responses susceptible to neuromodulation, considering quantum physics principles of nonlocality and entanglement (both present in NPT). We discuss (a) why the priming effect does not explain the significant results; (b) the potential discovery of a new form of quantum-like implicit learning, which could scientifically resolve phenomena associated with anomalous cognitions (e.g., AIA); and (c) future research directions, including potential applications and clinical impact.


Asunto(s)
Encéfalo , Electroencefalografía , Aprendizaje , Humanos , Masculino , Femenino , Adulto , Electroencefalografía/métodos , Encéfalo/fisiología , Aprendizaje/fisiología , Adulto Joven , Teoría Cuántica , Anticipación Psicológica/fisiología , Cognición/fisiología
4.
Artículo en Inglés | MEDLINE | ID: mdl-39094927

RESUMEN

Attenuated functional processing of non-drug rewards in striatal regions is an important mechanism in the transition from normal to hazardous alcohol use. Recent interventions seek to enhance nondrug reward processing through mindfulness, a mechanism that targets attention regulation and self-regulatory processes. It is yet unclear which specific aspects of mindfulness and which stages of reward processing are relevant preventive targets, particularly in adolescence, where alcohol use is often initiated and reward relating processing streams undergo continuous maturation. Fifty-four 14- and 16-year-old adolescents (54% female) completed the monetary incentive delay task (MID) during event-related functional magnetic resonance imaging. Alcohol use and dispositional mindfulness facets were measured using self-report instruments. Mindful Attention Regulation was positively associated with anticipatory reward processing in ventral striatum, whereas feedback-related processing in dorsal striatum was associated with the mindfulness facet Body-Listening. Only Attention Regulation was additionally associated with frequency of alcohol consumption and mediated the relationship between functional activation in ventral striatum during reward anticipation and alcohol use. Attention Regulation, beyond other mindfulness facets, might contribute to potentially triggering neural mechanisms of anticipatory, but not feedback-related reward processing and alcohol use, presenting a potential target for preventive efforts in combating transitions to substance-related disorders in adolescents.


Asunto(s)
Cuerpo Estriado , Imagen por Resonancia Magnética , Atención Plena , Recompensa , Humanos , Adolescente , Femenino , Masculino , Cuerpo Estriado/diagnóstico por imagen , Cuerpo Estriado/fisiología , Atención/fisiología , Consumo de Alcohol en Menores/psicología , Anticipación Psicológica/fisiología , Consumo de Bebidas Alcohólicas/psicología
5.
Hum Mov Sci ; 97: 103259, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39110998

RESUMEN

Humans frequently prepare for agile movements by decreasing stability. This facilitates transitions between movements but increases vulnerability to external disruptions. Therefore, humans might weigh the risk of disruption against the gain in agility and scale their stability to the likelihood of having to perform an agility-demanding action. We used the theory of motor synergies to investigate how humans manage this stability-agility tradeoff under uncertainty. This theory has long quantified stability using the synergy index, and reduction in stability before movement transitions using anticipatory synergy adjustment (ASA). However, the impact of uncertainty - whether a quick action should be executed or inhibited - on ASA is unknown. Furthermore, the impact of ASA on execution and inhibition of the action is unclear. We combined multi-finger, isometric force production with the go/no-go paradigm. Thirty participants performed constant force (no-go task), rapid force pulse (go task), and randomized go and no-go trials (go/no-go task) in response to visual cues. We measured the pre-cue finger forces and computed ASA using the uncontrolled manifold method and quantified the spatio-temporal features of the force after the visual cue. We expected ASA in both go/no-go and go tasks, but larger ASA for the latter. Surprisingly, we observed ASA only for the go task. For the go/no-go task, 53% of participants increased stability before the cue. The high stability hindered performance, leading to increased errors in no-go trials and lower peak forces in go trials. These results align with the stability-agility tradeoff. It is puzzling why some participants increased stability even though 80% of the trials demanded agility. This study indicates that individual differences in the effect of task uncertainty and motor inhibition on ASA is unexplored in motor synergy theory and presents a method for further development.


Asunto(s)
Desempeño Psicomotor , Humanos , Desempeño Psicomotor/fisiología , Masculino , Femenino , Adulto , Incertidumbre , Adulto Joven , Dedos/fisiología , Señales (Psicología) , Movimiento/fisiología , Contracción Isométrica/fisiología , Inhibición Psicológica , Anticipación Psicológica/fisiología , Fenómenos Biomecánicos , Tiempo de Reacción
6.
J Neurophysiol ; 132(3): 695-709, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39018017

RESUMEN

Postural stabilization is essential to effectively interact with our environment. Humans preemptively adjust their posture to counteract impending disturbances, such as those encountered during interactions with moving objects, a phenomenon known as anticipatory postural adjustments (APAs). APAs are thought to be influenced by predictive models that incorporate object motion via retinal motion and extraretinal signals. Building on our previous work that examined APAs in relation to the perceived momentum of moving objects, here we explored the impact of object motion within different visual field sectors on the human capacity to anticipate motion and prepare APAs for contact between virtual moving objects and the limb. Participants interacted with objects moving toward them under different gaze conditions. In one condition, participants fixated on either a central point (central fixation) or left-right of the moving object (peripheral fixation), whereas in another, they followed the moving object with smooth pursuit eye movements (SPEMs). We found that APAs had the smallest magnitude in the central fixation condition and that no notable differences in APAs were apparent between the SPEM and peripheral fixation conditions. This suggests that the visual system can accurately perceive motion of objects in peripheral vision for posture stabilization. Using Bayesian model averaging, we also evaluated the contribution of different gaze variables, such as eye velocity and gain (ratio of eye and object velocity) and showed that both eye velocity and gain signals were significant predictors of APAs. Taken together, our study underscores the roles of oculomotor signals in the modulation of APAs.NEW & NOTEWORTHY We show that the human visuomotor system can detect motion in peripheral vision and make anticipatory adjustments to posture before contact with moving objects, just as effectively as when the eye movement system tracks those objects with smooth pursuit eye movements. These findings pave the way for research into how age-induced changes in spatial vision, eye movements, and motion perception could affect the control of limb movements and postural stability during motion-mediated interactions with objects.


Asunto(s)
Percepción de Movimiento , Seguimiento Ocular Uniforme , Humanos , Seguimiento Ocular Uniforme/fisiología , Masculino , Femenino , Adulto , Percepción de Movimiento/fisiología , Adulto Joven , Fijación Ocular/fisiología , Anticipación Psicológica/fisiología , Equilibrio Postural/fisiología , Postura/fisiología , Campos Visuales/fisiología
7.
Cognition ; 251: 105887, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39018636

RESUMEN

Goal-directed actions are performed in order to attain certain sensory consequences in the world. However, expected attributes of these consequences can affect the kinetics of the action. In a set of three studies (n = 120), we examined how expected attributes of stimulus outcome (intensity) shape the kinetics of the triggering action (applied force), even when the action kinetic and attribute are independent. We show that during action execution (button presses), the expected intensity of sensory outcome affects the applied force of the stimulus-producing action in an inverse fashion. Thus, participants applied more force when the expected intensity of the outcome was low (vs. high intensity outcome). In the absence of expectations or when actions were performed in response to the sensory event, no intensity-dependent force modulations were found. Thus, expectations of stimulus intensity and causality play an important role in shaping action kinetics. Finally, we examined the relationship between kinetics and perception and found no influence of applied force level on perceptual detection of low intensity (near-threshold) outcome stimuli, suggesting no causal link between the two. Taken together, our results demonstrate that action kinetics are embedded with high-level context such as the expectation of consequence intensity and the causal relationship with environmental cues.


Asunto(s)
Desempeño Psicomotor , Humanos , Masculino , Femenino , Adulto Joven , Adulto , Desempeño Psicomotor/fisiología , Anticipación Psicológica/fisiología , Objetivos
8.
J Affect Disord ; 362: 779-787, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39029684

RESUMEN

BACKGROUND: Reward processing dysfunction is a core characteristic of major depressive disorder (MDD), yet event-related potential (ERP) research in MDD has predominantly focused on reward receipt as opposed to anticipation. The stimulus-preceding negativity (SPN) ERP reflects anticipatory brain processing. This study examines whether individuals with MDD exhibit deficits during reward anticipation as evidenced by altered SPN amplitude. METHODS: We assessed prefeedback-SPN amplitudes during a monetary incentive delay (MID) task in individuals with MDD (n = 142, 99 with comorbid anxiety disorders [MDD + ANX]) compared to Controls (n = 37). A mixed analysis of variance was performed on prefeedback-SPN amplitude and behavioral measures, with group (MDD, MDD + ANX, Control) as the between-subjects factor, and feedback (gain, loss) and electrode (F3, F4, Fz, C3, C4, Cz, P3, P4, Pz) as within-subjects factors. RESULTS: A group main effect revealed faster reaction times for the Control group than MDD and MDD + ANX groups. A group x feedback interaction indicated that the MDD subgroup had smaller prefeedback-SPN amplitudes than MDD + ANX and Control groups when anticipating gain feedback. Additionally, individuals with current MDD, irrespective of past MDD and comorbid anxiety, exhibited smaller SPN amplitudes than Controls prior to gain feedback. LIMITATIONS: The MID paradigm, designed for functional magnetic resonance imaging (fMRI) data acquisition, lacks optimization for ERP analysis. Moreover, the clinical groups included more females than the Control group. CONCLUSIONS: Reduced resource allocation to reward anticipation may differentiate MDD from MDD + ANX and Control groups. Further investigation of the neural mechanisms of distinct MDD phenotypes is warranted.


Asunto(s)
Anticipación Psicológica , Trastorno Depresivo Mayor , Electroencefalografía , Potenciales Evocados , Recompensa , Humanos , Trastorno Depresivo Mayor/fisiopatología , Trastorno Depresivo Mayor/psicología , Trastorno Depresivo Mayor/diagnóstico por imagen , Femenino , Masculino , Adulto , Potenciales Evocados/fisiología , Anticipación Psicológica/fisiología , Trastornos de Ansiedad/fisiopatología , Trastornos de Ansiedad/psicología , Tiempo de Reacción/fisiología , Persona de Mediana Edad , Adulto Joven , Motivación/fisiología , Encéfalo/fisiopatología , Encéfalo/diagnóstico por imagen
9.
Exp Brain Res ; 242(9): 2177-2191, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38992203

RESUMEN

We explored two types of anticipatory synergy adjustments (ASA) during accurate four-finger total force production task. The first type is a change in the index of force-stabilizing synergy during a steady state when a person is expecting a signal to produce a quick force change, which is seen even when the signal does not come (steady-state ASA). The other type is the drop in in the synergy index prior to a planned force change starting at a known time (transient ASA). The subjects performed a task of steady force production at 10% of maximal voluntary contraction (MVC) followed by a ramp to 20% MVC over 1 s, 3 s, and as a step function (0 s). In another task, in 50% of the trials during the steady-state phase, an unexpected signal could come requiring a quick force pulse to 20% MVC (0-surprise). Inter-trial variance in the finger force space was used to quantify the index of force-stabilizing synergy within the uncontrolled manifold hypothesis. We observed significantly lower synergy index values during the steady state in the 0-ramp trials compared to the 1-ramp and 3-ramp trials. There was also larger transient ASA during the 0-ramp trials. In the 0-surprise condition, the synergy index was significantly higher compared to the 0-ramp condition whereas the transient ASA was significantly larger. The finding of transient ASA scaling is of importance for clinical studies, which commonly involve populations with slower actions, which can by itself be associated with smaller ASAs. The participants varied the sharing pattern of total force across the fingers more in the task with "surprises". This was coupled to more attention to precision of performance, i.e., inter-trial deviations from the target as reflected in smaller variance affecting total force, possibly reflecting higher concentration on the task, which the participants perceived as more challenging compared to a similar task without surprise targets.


Asunto(s)
Dedos , Desempeño Psicomotor , Humanos , Masculino , Femenino , Desempeño Psicomotor/fisiología , Adulto Joven , Adulto , Dedos/fisiología , Anticipación Psicológica/fisiología , Tiempo de Reacción/fisiología , Movimiento/fisiología
10.
Cognition ; 250: 105869, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38971021

RESUMEN

When people indicate the vanishing location of a moving target that suddenly disappears, systematic errors forward (in the direction of motion) and downward (in the direction of gravity) emerge. These spatial displacements were coined, respectively, Representational Momentum and Representational Gravity, and are believed to reflect internalized ecologically relevant physical invariants useful for the anticipation of future states of an event. Previous research has shown that sports athletes exhibit increased Representational Momentum, indicating enhanced motion extrapolation and anticipation, albeit it is still not clear up to what degree this effect is specific for the expertise context or if it generalizes to other dynamic events. Furthermore, the influence of expertise on Representational Gravity, particularly in contexts where anticipation of vertically moving objects is crucial, remains understudied. This study aimed to address these gaps by focusing on Volleyball as a context of expertise due to the prevalence of fast vertically moving balls. Volleyball athletes and non-athletes indicated the perceived offset location of a smoothly moving target, which moved at a constant speed or was subjected to acceleration/deceleration, embedded either in a Volleyball or neutral context. Outcomes revealed that for the Volleyball context, athletes, but not non-athletes, revealed a significant trend to misperceive targets moving along the left diagonal to be further displaced forward beyond what would be expected due to Representational Momentum alone. This finding is discussed in relation to the natural statistics of Volleyball games, where crossed ball trajectories, particularly by the outside hitter, are more prevalent, fast, and offensive, requiring better anticipation to be efficiently dealt with.


Asunto(s)
Atletas , Percepción de Movimiento , Voleibol , Humanos , Voleibol/fisiología , Masculino , Femenino , Adulto Joven , Percepción de Movimiento/fisiología , Adulto , Anticipación Psicológica/fisiología , Gravitación
11.
Schizophr Res ; 271: 253-261, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39067367

RESUMEN

Social anhedonia is a hallmark symptom of schizophrenia. Discrepancies in anticipated versus consummatory pleasure for non-social stimuli are well-documented. Thus, a similar emotional paradox may underlie social anhedonia. If so, our understanding of social anhedonia-including how to treat it in schizophrenia-could be enhanced. This project used a 5-day experience sampling method (ESM) to measure discrepancies between anticipated and consummatory pleasure for real-world social activities in people with schizophrenia and healthy controls (n = 30/group). ESM results were compared to laboratory assessments of negative symptoms and neurocognition. The schizophrenia group exhibited similar levels of anticipated and consummatory social pleasure as controls throughout daily life, and both groups were accurate in their short-term predictions of pleasure. Clinical interviews revealed those with schizophrenia showed significant deficits in long-term social pleasure prediction (i.e., a 1-week timeframe). Thus, people with schizophrenia may exhibit differences in ability to predict pleasure in the short-term versus the long-term. Negative symptoms and neurocognition were related to anticipated, but not consummatory, social pleasure, suggesting anhedonia is driven by deficits in thinking about pleasure, rather than inability to experience pleasure. Clinical implications include focusing on building upon short-term ability to predict pleasure in therapy to increase social motivation in schizophrenia.


Asunto(s)
Anhedonia , Placer , Esquizofrenia , Humanos , Anhedonia/fisiología , Femenino , Masculino , Adulto , Esquizofrenia/fisiopatología , Placer/fisiología , Persona de Mediana Edad , Psicología del Esquizofrénico , Evaluación Ecológica Momentánea , Anticipación Psicológica/fisiología , Conducta Social
12.
J Cogn Neurosci ; 36(10): 2067-2083, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39023362

RESUMEN

The N1/P2 amplitude reduction for self-generated tones in comparison to external tones in EEG, which has recently also been described for action observation, is an example of the so-called sensory attenuation. Whether this effect is dependent on motor-based or general predictive mechanisms is unclear. Using a paradigm, in which actions (button presses) elicited tones in only half the trials, this study examined how the processing of the tones is modulated by the prediction error in each trial in a self-performed action compared with action observation. In addition, we considered the effect of temporal predictability by adding a third condition, in which visual cues were followed by external tones in half the trials. The attenuation result patterns differed for N1 and P2 amplitudes, but neither showed an attenuation effect beyond temporal predictability. Interestingly, we found that both N1 and P2 amplitudes reflected prediction errors derived from a reinforcement learning model, in that larger errors coincided with larger amplitudes. This effect was stronger for tones following button presses compared with cued external tones, but only for self-performed and not for observed actions. Taken together, our results suggest that attenuation effects are partially driven by general predictive mechanisms irrespective of self-performed actions. However, the stronger prediction-error effects for self-generated tones suggest that distinct motor-related factors beyond temporal predictability, potentially linked to reinforcement learning, play a role in the underlying mechanisms. Further research is needed to validate these initial findings as the calculation of the prediction errors was limited by the design of the experiment.


Asunto(s)
Electroencefalografía , Humanos , Masculino , Femenino , Adulto Joven , Adulto , Percepción Auditiva/fisiología , Desempeño Psicomotor/fisiología , Potenciales Evocados/fisiología , Señales (Psicología) , Anticipación Psicológica/fisiología , Estimulación Acústica , Factores de Tiempo
13.
Conscious Cogn ; 123: 103699, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39002298

RESUMEN

Semantic relatedness and expectation were investigated in inattentional blindness-failure to perceive an unexpected object in plain sight when attention is engaged elsewhere. Participants named primary-task pictures and ignored distractor pictures. Four trials preceded a 'critical' trial where an unexpected six-letter-word appeared at fixation, simultaneously with the pictures. In Experiment 1, we found robust effects for both in-lab and on-line-Zoom methodology. More participants reported the unexpected word semantically-related to the primary-task pictures than a semantically-unrelated word. In Experiment 2, expectations were violated, by changing the semantic category of the primary-task pictures. More participants reported the unexpected word semantically-related to the unexpected picture category than a semantically-unrelated word. When attentional resources are consumed by a task, a violation to task expectations is not enough to reorient attention to an unexpected word. Attention reorients to what is meaningful to the task, and what is meaningful is updated in light of unexpected information.


Asunto(s)
Atención , Semántica , Humanos , Atención/fisiología , Adulto , Adulto Joven , Masculino , Femenino , Reconocimiento Visual de Modelos/fisiología , Percepción Visual/fisiología , Anticipación Psicológica/fisiología
14.
Nature ; 632(8027): 1092-1100, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39048016

RESUMEN

Placebo effects are notable demonstrations of mind-body interactions1,2. During pain perception, in the absence of any treatment, an expectation of pain relief can reduce the experience of pain-a phenomenon known as placebo analgesia3-6. However, despite the strength of placebo effects and their impact on everyday human experience and the failure of clinical trials for new therapeutics7, the neural circuit basis of placebo effects has remained unclear. Here we show that analgesia from the expectation of pain relief is mediated by rostral anterior cingulate cortex (rACC) neurons that project to the pontine nucleus (rACC→Pn)-a precerebellar nucleus with no established function in pain. We created a behavioural assay that generates placebo-like anticipatory pain relief in mice. In vivo calcium imaging of neural activity and electrophysiological recordings in brain slices showed that expectations of pain relief boost the activity of rACC→Pn neurons and potentiate neurotransmission in this pathway. Transcriptomic studies of Pn neurons revealed an abundance of opioid receptors, further suggesting a role in pain modulation. Inhibition of the rACC→Pn pathway disrupted placebo analgesia and decreased pain thresholds, whereas activation elicited analgesia in the absence of placebo conditioning. Finally, Purkinje cells exhibited activity patterns resembling those of rACC→Pn neurons during pain-relief expectation, providing cellular-level evidence for a role of the cerebellum in cognitive pain modulation. These findings open the possibility of targeting this prefrontal cortico-ponto-cerebellar pathway with drugs or neurostimulation to treat pain.


Asunto(s)
Vías Nerviosas , Percepción del Dolor , Dolor , Efecto Placebo , Animales , Femenino , Masculino , Ratones , Analgesia , Anticipación Psicológica/fisiología , Señalización del Calcio , Cerebelo/citología , Cerebelo/fisiología , Cognición/fisiología , Electrofisiología , Perfilación de la Expresión Génica , Giro del Cíngulo/citología , Giro del Cíngulo/fisiología , Ratones Endogámicos C57BL , Neuronas/fisiología , Dolor/fisiopatología , Dolor/prevención & control , Dolor/psicología , Manejo del Dolor/métodos , Manejo del Dolor/psicología , Manejo del Dolor/tendencias , Percepción del Dolor/fisiología , Umbral del Dolor/fisiología , Umbral del Dolor/psicología , Puente/citología , Puente/fisiología , Corteza Prefrontal/citología , Corteza Prefrontal/fisiología , Células de Purkinje/fisiología , Receptores Opioides/metabolismo , Transmisión Sináptica
15.
PLoS One ; 19(7): e0295216, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38995957

RESUMEN

Subjective estimates of duration are affected by emotional expectations about the future. For example, temporal intervals preceding a threatening event such as an electric shock are estimated as longer than intervals preceding a non-threatening event. However, it has not been unequivocally shown that such temporal overestimation occurs also when anticipating a similarly arousing but appealing event. In this study, we examined how anticipation of visual erotic material influenced perceived duration. Participants did a temporal bisection task, where they estimated durations of visual cues relative to previously learned short and long standard durations. The color of the to-be-timed visual cue signalled either a chance of seeing a preferred erotic picture at the end of the interval or certainty of seeing a neutral grey bar instead. The results showed that anticipating an appealing event increased the likelihood of estimating the cue duration as long as compared to the anticipation of a grey bar. Further analyses showed that this temporal overestimation effect was stronger for those who rated the anticipated erotic pictures as more sexually arousing. The results thus indicate that anticipation of appealing events has a similar dilating effect on perceived duration as does the anticipation of aversive events.


Asunto(s)
Anticipación Psicológica , Humanos , Femenino , Masculino , Adulto , Adulto Joven , Anticipación Psicológica/fisiología , Percepción del Tiempo/fisiología , Señales (Psicología) , Estimulación Luminosa , Conducta Sexual/psicología , Conducta Sexual/fisiología , Percepción Visual/fisiología , Nivel de Alerta/fisiología , Literatura Erótica/psicología , Factores de Tiempo
16.
Psychosom Med ; 86(7): 591-602, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38973749

RESUMEN

OBJECTIVE: Expectations are highlighted as a key component in placebo effects. However, there are different approaches to whether and how placebo studies should account for expectations, and the direct contribution has yet to be estimated in meta-analyses. Using different methodological approaches, this meta-analysis and systematic review examines the extent to which expectations contribute to pain in placebo studies. METHODS: The databases PubMed, PsycINFO, Embase, and Web of Science were searched for placebo analgesia mechanism studies with numerical measures of both expectations and pain. Thirty-one studies, comprising 34 independent study populations (1566 subjects: patients and healthy participants) were included. Two meta-analyses were conducted: meta-analysis 1, using study-level data, estimated the effect of expectation interventions without taking measures of expectations into account (expectations assumed); and meta-analysis 2, using individual-level data, estimated the direct impact of participants' expectations on pain (expectations assessed). Risk of bias was assessed using the Cochrane risk-of-bias tool. RESULTS: Meta-analysis 1 showed a moderate effect of expectation interventions over no expectation intervention on pain intensity (Hedges g = 0.45, I2 = 54.19). Based on 10 studies providing individual-level data, meta-analysis 2 showed that expectations predicted pain intensity in placebo and control groups ( b = 0.36, SE = 0.05), although inconsistently across study methodologies. CONCLUSIONS: Participants' expectations contributed moderately to pain in placebo analgesia studies. However, this may largely be influenced by how we measure expectations and how their contribution is conceptualized and analyzed-both within and across studies.


Asunto(s)
Analgesia , Efecto Placebo , Humanos , Analgesia/métodos , Anticipación Psicológica/fisiología , Dolor/tratamiento farmacológico , Dolor/psicología
17.
J Mot Behav ; 56(5): 626-641, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38958336

RESUMEN

In the Serial Reaction Time Task, participants respond to several stimuli usually being unaware that the stimuli follow a predefined sequence while still learning the sequence. In the present study, we aimed to clearly separate explicit intentional learning from implicit incidental learning by either informing participants about all details of the sequence or not informing participants about the existence of the sequence. Further, we explored the influence of anticipatory cues during practice while anticipatory cues were either presented (extrinsically triggered anticipation) or not presented (self-reliant intrinsic anticipation). Participants were tested before and after practice in the Practice Sequence and a Control Sequence. To test automatization, tests were performed in Single-Task and Dual-Task Blocks. Results showed that after learning with explicit instructions, participants memorized the sequence more deeply and executed the sequence faster than after learning without explicit instructions. Further, by learning with anticipatory cues, participants memorized the sequence less deeply and executed the sequence slower than by learning without anticipatory cues. Unexpectedly, automatization was sequence-unspecific and independent of the practice conditions. In conclusion, detailed explicit prior information about the sequence facilitates sequence learning while anticipatory online cues during practice hamper sequence learning.


Asunto(s)
Señales (Psicología) , Práctica Psicológica , Tiempo de Reacción , Humanos , Masculino , Femenino , Tiempo de Reacción/fisiología , Adulto , Adulto Joven , Anticipación Psicológica/fisiología , Desempeño Psicomotor/fisiología , Intención , Aprendizaje Seriado/fisiología , Aprendizaje/fisiología
18.
Stress ; 27(1): 2330009, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38952223

RESUMEN

Dehydroepiandrosterone (DHEA) and cortisol release appear to have contrasting effects on stress perception during stressful tasks. This study aimed to investigate anticipatory examination stress in college students by considering DHEA, cortisol, psycho-emotional aspects and examination performance. Seventy-six students (66 females, 10 males; age range 18-25 years) provided saliva samples and completed questionnaires in two sessions 48 hours apart. During the second session, the students performed the examination. The questionnaires used were the State-Trait Anxiety Inventory, the Positive and Negative Affect Scale, and the Brief-Coping Orientation to Problems Experienced Inventory. DHEA, cortisol, anxiety and negative affect showed an anticipatory rise before the examination (all ps < 0.001). This rise of DHEA and cortisol was associated with lower positive affect (p = 0.001 and p = 0.043, respectively). However, only the DHEA anticipatory levels were linked to poorer examination marks (p = 0.020). Higher levels of the DHEA/cortisol ratio in anticipation of the examination were related to lower scores on the support-seeking strategy (p = 0.022). There was no association between DHEA and cortisol levels and anxiety, negative affect, active and avoidant coping strategies, or academic record. These results suggest that how DHEA and cortisol respond in anticipation of examination stress significantly impacts students' emotional well-being during examination periods and how they cope with stress. They also suggest that levels of DHEA in anticipation of an academic stressor have detrimental effects on stress management.


Asunto(s)
Adaptación Psicológica , Afecto , Ansiedad , Deshidroepiandrosterona , Hidrocortisona , Saliva , Estrés Psicológico , Estudiantes , Humanos , Masculino , Femenino , Hidrocortisona/metabolismo , Hidrocortisona/análisis , Deshidroepiandrosterona/análisis , Deshidroepiandrosterona/metabolismo , Adulto Joven , Estudiantes/psicología , Adulto , Adolescente , Saliva/química , Estrés Psicológico/metabolismo , Estrés Psicológico/psicología , Afecto/fisiología , Ansiedad/psicología , Encuestas y Cuestionarios , Anticipación Psicológica/fisiología , Universidades
19.
Cortex ; 177: 346-362, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38917725

RESUMEN

Prediction has a fundamental role in language processing. However, predictions can be made at different levels, and it is not always clear whether speech sounds, morphemes, words, meanings, or communicative functions are anticipated during dialogues. Previous studies reported specific brain signatures of communicative pragmatic function, in particular enhanced brain responses immediately after encountering an utterance used to request an object from a partner, but relatively smaller ones when the same utterance was used for naming the object. The present experiment now investigates whether similar neuropragmatic signatures emerge in recipients before the onset of upcoming utterances carrying different predictable communicative functions. Trials started with a context question and object pictures displayed on the screen, raising the participant's expectation that words from a specific semantic category (food or tool) would subsequently be used to either name or request one of the objects. Already 600 msec before utterance onset, a larger prediction potential was observed when a request was anticipated relative to naming expectation. As this result is congruent with the neurophysiological difference previously observed right after the critical utterance, the anticipatory brain activity may index predictions about the social-communicative function of upcoming utterances. In addition, we also found that the predictable semantic category of the upcoming word was likewise reflected in the anticipatory brain potential. Thus, the neurophysiological characteristics of the prediction potential can capture different types of upcoming linguistic information, including semantic and pragmatic aspects of an upcoming utterance and communicative action.


Asunto(s)
Encéfalo , Comunicación , Electroencefalografía , Semántica , Humanos , Masculino , Femenino , Adulto , Adulto Joven , Encéfalo/fisiología , Potenciales Evocados/fisiología , Lenguaje , Habla/fisiología , Anticipación Psicológica/fisiología , Tiempo de Reacción/fisiología
20.
Cortex ; 177: 235-252, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38875737

RESUMEN

The ability to inhibit movements is an essential component of a healthy executive control system. Two distinct but commonly used tasks to assess motor inhibition are the stop signal task (SST) and the anticipated response inhibition (ARI) task. The SST and ARI tasks are similar in that they both require cancelation of a prepotent movement; however, the SST involves cancelation of a speeded reaction to a temporally unpredictable signal, while the ARI task involves cancelation of an anticipated response that the participant has prepared to enact at a wholly predictable time. 33 participants (mean age = 33.3 years, range = 18-55 years) completed variants of the SST and ARI task. In each task, the majority of trials required bimanual button presses, while on a subset of trials a stop signal indicated that one of the presses should be cancelled (i.e., motor selective inhibition). Additional variants of the tasks also included trials featuring signals which were to be ignored, allowing for insights into the attentional component of the inhibitory response. Electromyographic (EMG) recordings allowed detailed comparison of the characteristics of voluntary action and cancellation. The speed of the inhibitory process was not influenced by whether the enacted movement was reactive (SST) or anticipated (ARI task). However, the ongoing (non-cancelled) component of anticipated movements was more efficient than reactive movements, as a result of faster action reprogramming (i.e., faster ongoing actions following successful motor selective inhibition). Older age was associated with both slower inhibition and slower action reprogramming across all reactive and anticipated tasks.


Asunto(s)
Electromiografía , Inhibición Psicológica , Movimiento , Desempeño Psicomotor , Tiempo de Reacción , Humanos , Adulto , Masculino , Femenino , Persona de Mediana Edad , Adolescente , Adulto Joven , Desempeño Psicomotor/fisiología , Movimiento/fisiología , Tiempo de Reacción/fisiología , Función Ejecutiva/fisiología , Atención/fisiología , Anticipación Psicológica/fisiología
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