As duas primeiras semanas de vida em ratos são críticas para o desenvolvimento, pois os animais são suscetíveis a influências ambientais. Diversos parâmetros neuroendócrinos e comportamentais podem ser influenciados, a curto e a longo prazo, pelas interações com a mãe, assim como por estressores. Entre esses estressores, um ambiente precoce socialmente aversivo pode alterar os comportamentos sociais, a ansiedade e as respostas neuroendócrinas ao estresse em adultos. O foco deste trabalho foi investigar o impacto do paradigma de provocação social na díade mãe-filhote sobre os comportamentos sociais e as respostas hormonais da prole em três idades. A provocação social foi realizada nos dias pós-natais (PP) 2 e 5. O comportamento maternal das lactantes foi registrado em PP3, 4, e 6. Os filhotes foram submetidos ao teste de preferência olfatória em PP7, o comportamento de brincadeira em juvenis foi registrado em PP30 e os ratos adultos (a partir de PP80) foram submetidos aos testes de campo aberto, labirinto em cruz elevado e interação social. Os adultos também foram expostos ao estresse por contenção (PP90). Os resultados mostraram que a intervenção aumentou a presença das mães no ninho. A intervenção reduziu o tempo gasto pelos filhotes no lado da maravalha do ninho, reduziu os níveis plasmáticos de ocitocina e prolactina, porém, aumentou os níveis de arginina-vasopressina. Nos juvenis, a intervenção reduziu a brincadeira de luta e os níveis plasmáticos de arginina-vasopressina. Nos adultos, a intervenção não levou a alterações na ansiedade e nas respostas hormonais ao estresse, porém, reduziu a latência para os comportamentos agressivos e os níveis plasmáticos basais de ocitocina. Conforme observado nas lactantes e nos neonatos, a provocação social levou a uma alteração da relação mãe-filhote, afetando, também, hormônios relacionados ao comportamento afiliativo em neonatos. Da mesma forma, a redução da brincadeira de luta em juvenis expostos à intervenção neonatal pode ter ocorrido devido à alteração da argininavasopressina, hormônio envolvido nesse comportamento. Apesar da intervenção não ter alterado a ansiedade e as respostas hormonais ao estresse em adultos, afetou de maneira específica o comportamento agressivo, reduzindo a sua latência. Este achado pode ser relacionado à ocitocina diminuída, conhecida por ter efeitos antiagressivos. Logo, sugerimos que a provocação social altere, tanto de forma precoce quanto duradoura, os comportamentos sociais, assim como os hormônios responsáveis pela modulação desses parâmetros. / The first two weeks of life in rats are critical for development because the animals are susceptible to environmental influences. A variety of neuroendocrine and behavioral parameters may be influenced in a short or long lasting way by the interactions with the mother as well as by stressors. Among these stressors, a socially aversive environment may alter social behaviors, anxiety and neuroendocrine responses to stress in adult subjects. The focus of this work was to investigate the impact of the social instigation paradigm on motherlitter dyad over social behaviors and hormonal responses in rats at 3 ages. Social instigation was carried out at postpartum days (PP) 2 and 5. Maternal behavior from lactating rats was registered at PP3, 4 and 6. Pups were submitted to the nest odor preference test at PP7, play behavior was registered in juveniles at PP30, and adult rats (starting at PP80) were submitted to the open field, elevated plus maze and social interaction tests. Adult rats were also submitted to restraint stress. Results show that the intervention increased presence in nest of lactating rats. The intervention reduced time spent on nest bedding side in pups, decreased oxytocin and prolactin plasma levels, however, increased arginine-vasopressin levels. Juveniles submitted to the neonatal intervention had reduced play-fighting frequencies and arginine-vasopressin levels. In adults, the intervention has not altered anxiety and hormonal responses to stress, however, it decreased the latency for aggressive behaviors, as well as oxytocin basal levels. According to the outcomes observed in lactating rats and pups, social instigation altered mother-infant relationship, as well as levels of hormones involved in affiliative behavior in neonatal rats. Similarly, the reduced play-fighting in juveniles exposed to the intervention may be related to the decreased arginine-vasopressin levels, which is a hormone involved in such behavior. In spite of the intervention having not altered the anxiety and hormonal responses to stress in adult rats, it altered in a specific manner the aggressive behavior, reducing its latency. This finding may be related to the decreased oxytocin levels, which is a hormone known to have antiaggressive effects. Thus, we suggest that social instigation impairs early to late social behaviors, as well as the hormones responsible for the modulation of such parameters.

As duas primeiras semanas de vida em ratos são críticas para o desenvolvimento, pois os animais são suscetíveis a influências ambientais. Diversos parâmetros neuroendócrinos e comportamentais podem ser influenciados, a curto e a longo prazo, pelas interações com a mãe, assim como por estressores. Entre esses estressores, um ambiente precoce socialmente aversivo pode alterar os comportamentos sociais, a ansiedade e as respostas neuroendócrinas ao estresse em adultos. O foco deste trabalho foi investigar o impacto do paradigma de provocação social na díade mãe-filhote sobre os comportamentos sociais e as respostas hormonais da prole em três idades. A provocação social foi realizada nos dias pós-natais (PP) 2 e 5. O comportamento maternal das lactantes foi registrado em PP3, 4, e 6. Os filhotes foram submetidos ao teste de preferência olfatória em PP7, o comportamento de brincadeira em juvenis foi registrado em PP30 e os ratos adultos (a partir de PP80) foram submetidos aos testes de campo aberto, labirinto em cruz elevado e interação social. Os adultos também foram expostos ao estresse por contenção (PP90). Os resultados mostraram que a intervenção aumentou a presença das mães no ninho. A intervenção reduziu o tempo gasto pelos filhotes no lado da maravalha do ninho, reduziu os níveis plasmáticos de ocitocina e prolactina, porém, aumentou os níveis de arginina-vasopressina. Nos juvenis, a intervenção reduziu a brincadeira de luta e os níveis plasmáticos de arginina-vasopressina. Nos adultos, a intervenção não levou a alterações na ansiedade e nas respostas hormonais ao estresse, porém, reduziu a latência para os comportamentos agressivos e os níveis plasmáticos basais de ocitocina. Conforme observado nas lactantes e nos neonatos, a provocação social levou a uma alteração da relação mãe-filhote, afetando, também, hormônios relacionados ao comportamento afiliativo em neonatos. Da mesma forma, a redução da brincadeira de luta em juvenis expostos à intervenção neonatal pode ter ocorrido devido à alteração da argininavasopressina, hormônio envolvido nesse comportamento. Apesar da intervenção não ter alterado a ansiedade e as respostas hormonais ao estresse em adultos, afetou de maneira específica o comportamento agressivo, reduzindo a sua latência. Este achado pode ser relacionado à ocitocina diminuída, conhecida por ter efeitos antiagressivos. Logo, sugerimos que a provocação social altere, tanto de forma precoce quanto duradoura, os comportamentos sociais, assim como os hormônios responsáveis pela modulação desses parâmetros. / The first two weeks of life in rats are critical for development because the animals are susceptible to environmental influences. A variety of neuroendocrine and behavioral parameters may be influenced in a short or long lasting way by the interactions with the mother as well as by stressors. Among these stressors, a socially aversive environment may alter social behaviors, anxiety and neuroendocrine responses to stress in adult subjects. The focus of this work was to investigate the impact of the social instigation paradigm on motherlitter dyad over social behaviors and hormonal responses in rats at 3 ages. Social instigation was carried out at postpartum days (PP) 2 and 5. Maternal behavior from lactating rats was registered at PP3, 4 and 6. Pups were submitted to the nest odor preference test at PP7, play behavior was registered in juveniles at PP30, and adult rats (starting at PP80) were submitted to the open field, elevated plus maze and social interaction tests. Adult rats were also submitted to restraint stress. Results show that the intervention increased presence in nest of lactating rats. The intervention reduced time spent on nest bedding side in pups, decreased oxytocin and prolactin plasma levels, however, increased arginine-vasopressin levels. Juveniles submitted to the neonatal intervention had reduced play-fighting frequencies and arginine-vasopressin levels. In adults, the intervention has not altered anxiety and hormonal responses to stress, however, it decreased the latency for aggressive behaviors, as well as oxytocin basal levels. According to the outcomes observed in lactating rats and pups, social instigation altered mother-infant relationship, as well as levels of hormones involved in affiliative behavior in neonatal rats. Similarly, the reduced play-fighting in juveniles exposed to the intervention may be related to the decreased arginine-vasopressin levels, which is a hormone involved in such behavior. In spite of the intervention having not altered the anxiety and hormonal responses to stress in adult rats, it altered in a specific manner the aggressive behavior, reducing its latency. This finding may be related to the decreased oxytocin levels, which is a hormone known to have antiaggressive effects. Thus, we suggest that social instigation impairs early to late social behaviors, as well as the hormones responsible for the modulation of such parameters.

As duas primeiras semanas de vida em ratos são críticas para o desenvolvimento, pois os animais são suscetíveis a influências ambientais. Diversos parâmetros neuroendócrinos e comportamentais podem ser influenciados, a curto e a longo prazo, pelas interações com a mãe, assim como por estressores. Entre esses estressores, um ambiente precoce socialmente aversivo pode alterar os comportamentos sociais, a ansiedade e as respostas neuroendócrinas ao estresse em adultos. O foco deste trabalho foi investigar o impacto do paradigma de provocação social na díade mãe-filhote sobre os comportamentos sociais e as respostas hormonais da prole em três idades. A provocação social foi realizada nos dias pós-natais (PP) 2 e 5. O comportamento maternal das lactantes foi registrado em PP3, 4, e 6. Os filhotes foram submetidos ao teste de preferência olfatória em PP7, o comportamento de brincadeira em juvenis foi registrado em PP30 e os ratos adultos (a partir de PP80) foram submetidos aos testes de campo aberto, labirinto em cruz elevado e interação social. Os adultos também foram expostos ao estresse por contenção (PP90). Os resultados mostraram que a intervenção aumentou a presença das mães no ninho. A intervenção reduziu o tempo gasto pelos filhotes no lado da maravalha do ninho, reduziu os níveis plasmáticos de ocitocina e prolactina, porém, aumentou os níveis de arginina-vasopressina. Nos juvenis, a intervenção reduziu a brincadeira de luta e os níveis plasmáticos de arginina-vasopressina. Nos adultos, a intervenção não levou a alterações na ansiedade e nas respostas hormonais ao estresse, porém, reduziu a latência para os comportamentos agressivos e os níveis plasmáticos basais de ocitocina. Conforme observado nas lactantes e nos neonatos, a provocação social levou a uma alteração da relação mãe-filhote, afetando, também, hormônios relacionados ao comportamento afiliativo em neonatos. Da mesma forma, a redução da brincadeira de luta em juvenis expostos à intervenção neonatal pode ter ocorrido devido à alteração da argininavasopressina, hormônio envolvido nesse comportamento. Apesar da intervenção não ter alterado a ansiedade e as respostas hormonais ao estresse em adultos, afetou de maneira específica o comportamento agressivo, reduzindo a sua latência. Este achado pode ser relacionado à ocitocina diminuída, conhecida por ter efeitos antiagressivos. Logo, sugerimos que a provocação social altere, tanto de forma precoce quanto duradoura, os comportamentos sociais, assim como os hormônios responsáveis pela modulação desses parâmetros. / The first two weeks of life in rats are critical for development because the animals are susceptible to environmental influences. A variety of neuroendocrine and behavioral parameters may be influenced in a short or long lasting way by the interactions with the mother as well as by stressors. Among these stressors, a socially aversive environment may alter social behaviors, anxiety and neuroendocrine responses to stress in adult subjects. The focus of this work was to investigate the impact of the social instigation paradigm on motherlitter dyad over social behaviors and hormonal responses in rats at 3 ages. Social instigation was carried out at postpartum days (PP) 2 and 5. Maternal behavior from lactating rats was registered at PP3, 4 and 6. Pups were submitted to the nest odor preference test at PP7, play behavior was registered in juveniles at PP30, and adult rats (starting at PP80) were submitted to the open field, elevated plus maze and social interaction tests. Adult rats were also submitted to restraint stress. Results show that the intervention increased presence in nest of lactating rats. The intervention reduced time spent on nest bedding side in pups, decreased oxytocin and prolactin plasma levels, however, increased arginine-vasopressin levels. Juveniles submitted to the neonatal intervention had reduced play-fighting frequencies and arginine-vasopressin levels. In adults, the intervention has not altered anxiety and hormonal responses to stress, however, it decreased the latency for aggressive behaviors, as well as oxytocin basal levels. According to the outcomes observed in lactating rats and pups, social instigation altered mother-infant relationship, as well as levels of hormones involved in affiliative behavior in neonatal rats. Similarly, the reduced play-fighting in juveniles exposed to the intervention may be related to the decreased arginine-vasopressin levels, which is a hormone involved in such behavior. In spite of the intervention having not altered the anxiety and hormonal responses to stress in adult rats, it altered in a specific manner the aggressive behavior, reducing its latency. This finding may be related to the decreased oxytocin levels, which is a hormone known to have antiaggressive effects. Thus, we suggest that social instigation impairs early to late social behaviors, as well as the hormones responsible for the modulation of such parameters.

Contexte : Les personnes atteintes de trouble de personnalité limite (TPL) présenteraient un déficit de mentalisation, soit la capacité de percevoir et interpréter les états mentaux chez soi et chez l’autre. Dans le cadre de la relation mère-bébé, un tel déficit est susceptible d’entraîner des perturbations relationnelles ayant des conséquences néfastes sur le développement de l’enfant. L’orientation mentale se mesure par le biais des verbalisations du parent au sujet des états mentaux de son enfant et constitue donc un reflet de la mentalisation du parent durant cette interaction. Toutefois, aucune étude n’a encore investigué l’orientation mentale chez des mères avec TPL durant l’interaction avec leur bébé. Objectif : Le but de cette étude était d’évaluer l’orientation mentale de 38 mères en interaction avec leur enfant âgé de 12 mois, incluant 10 mères atteintes de TPL et 28 sans diagnostic psychiatrique. Méthode: L’orientation mentale maternelle fut évaluée à partir de vidéos d’interaction mère-enfant dans un contexte de jeu libre. Le TPL a été identifié à l’aide du Structured Clinical Interview for DSM-III-R Personality Disorders (SCID-II). Résultats: Les mères atteintes de TPL ne se sont pas distingué concernant la fréquence de commentaires faisant référence aux états mentaux de leur bébé. Toutefois, les commentaires mentaux des mères souffrant de TPL se sont avérés être 4.7 fois plus fréquemment jugés non-appropriés à l’état mental de l’enfant comparés à ceux des mères sans diagnostic psychiatrique. Conclusions : Les commentaires mentaux des mères atteintes de TPL semblent plus fréquemment empreints d’erreurs d’interprétation des états mentaux de leur enfant, ce qui pourrait poser un risque pour le développement de l’enfant. / Background. Mothers with Borderline Personality Disorder (BPD) have been theorized to have decreased mentalization ability, which is the capacity to perceive and interpret mental states. This could potentially increase the risk for troubled relationships with their infants and therefore have adverse consequences on the social and emotional development of the child. Mind-mindedness (MM), assessed through the mother’s references to her infant’s mental states during an interaction, is one aspect of maternal behavior that relies heavily on the mother’s mentalizing ability. However, research has yet to examine MM in mothers with BPD. Aims. Our objective was to assess the MM ability of 38 mothers during interactions with their 12 month-old infants, including 10 with BPD and 28 without a psychiatric diagnosis. Method. Trained observers assessed maternal MM from 2 minutes of videotaped mother-infant free play. BPD was assessed by the Structured Clinical Interview for DSM-III-R-Personality Disorders (SCID-II). Results. Mothers with and without BPD did not differ in the frequency of comments referring to infant mental states. However, the mind- related comments made by mothers with BPD were 4.7 times more frequently judged as non- attuned to her infant’s mental state by a trained observer compared with those of controls without a psychiatric diagnosis. Conclusions. Mothers with and without BPD appear equally likely to envision and refer to mental states in their infants. However, mothers with BPD appear more likely to misread the mental states of their infants. This could put the child at risk for adverse developmental outcomes.

No description available.

L’esperienza di aspettare e di essere genitore di due gemelli è innegabilmente diversa rispetto alla gravidanza alla genitorialità nel caso di un singolo bambino. La nascita gemellare è associata a conseguenze mediche, sanitarie, socio-emotive, psicologiche e dello sviluppo. Lo scopo di questo lavoro è stato quello di aggiungere conoscenze rispetto agli aspetti unici legati alla gravidanza gemellare e alla genitorialità. Ho esaminato il modo in cui le future mamme vivono la loro gravidanza e come le madri sperimentano l’essere genitori di due gemelli e come queste interagiscono con i loro bambini nel periodo post-partum. Per studiare meglio l'esperienza di aspettare e di essere madre di due gemelli, i risultati sono stati confrontati con la letteratura esistente e sono stati utilizzati diversi progetti di ricerca. È stata valutata la validità e le proprietà psicometriche della versione italiana del Baby Care Questionnaire; è stato valutato se l'esperienza unica di un gemello in attesa potesse influenzare negativamente l'attaccamento prenatale; è stato esplorato l'impatto della nascita gemellare sull'interazione madre-figlio nel primo periodo post-partum. Questa tesi ha stabilito che le madri di gemelli hanno esigenze particolari e affrontano sfide uniche. Le madri di gemelli sembrano essere meno adattate dal punto di vista psicologico alla loro gravidanza in termini di basso livello di attaccamento prenatale. Anche la costruzione di una relazione stretta e positiva potrebbe essere più difficile nel caso dei gemelli. / The experience of expecting and parenting twins is undeniably different from that of a singleton pregnancy and parenthood. Twin births are associated with medical, health care, socio-emotional, psychological and developmental consequences. The aim of this work was to add knowledge concerning the unique aspects of expecting and parenting twins. I examined the way the mothers-to-be live their pregnancy as well as how mothers experience parenting twins and interact with their babies in the post-partum period. To better investigate the unique experience of expecting and parenting twins, results were compared with the existing literature and different research design were used. It was evaluated the validity and the psychometric properties of the Italian version of the Baby Care Questionnaire; it was investigated if the unique experience of expecting twin may adversely affect prenatal attachment; it was explored the impact of twin birth on mother-child interaction in the early post-partum period. This thesis established that mothers of twins have unique needs and face unique challenges. Mothers of twins seems to be less psychological adjusted to their pregnancy in terms of lower level of prenatal attachment. Also the building of a close and positive relationship could be more difficult in the case of twins.

Les nouveau-nés prématurés sont à risque de développer des séquelles neurodéveloppementales pouvant se manifester de la petite enfance jusqu’à l’âge adulte. La relation mère-enfant précoce figure parmi les facteurs pouvant améliorer leur neurodéveloppement. La principale composante de cette relation est la sensibilité maternelle, soit la capacité de détecter, d’interpréter et de répondre rapidement aux besoins du nouveau-né. Cependant, en raison de l’immaturité des nouveau-nés prématurés ainsi que du stress et de l’anxiété vécus par les mères pendant l’hospitalisation, celles-ci sont à risque de développer une sensibilité maternelle sous-optimale. De par leurs compétences, leurs valeurs et leurs activités réservées, les infirmières à l’unité de soins intensifs néonatals (USIN) jouent un rôle de premier plan pour favoriser la sensibilité maternelle dès l’hospitalisation des nouveau-nés prématurés. Les données scientifiques actuelles ne sont suffisantes ni en quantité ni en qualité afin d’orienter les interventions que pourraient concrètement réaliser les infirmières auprès de la dyade mère-nouveau-né prématuré afin de favoriser de façon très précoce, soit dès l’hospitalisation, la sensibilité maternelle. Le but de la thèse comportait deux volets : 1- développer une intervention infirmière très précoce selon une approche combinant la théorie et les données empiriques pour favoriser la sensibilité maternelle et le neurodéveloppement des nouveau-nés prématurés à l’USIN; et 2- mettre à l’essai et évaluer la faisabilité, l’acceptabilité et estimer les effets préliminaires de l’intervention infirmière sur la sensibilité maternelle et le neurodéveloppement des nouveau-nés prématurés à l’USIN. Une intervention infirmière novatrice multifactorielle nommée GP_Posit a été développée. GP_Posit est une intervention individuelle hebdomadaire durant laquelle l’infirmière crée une relation de participation guidée avec la mère, dans un contexte de participation aux soins et au positionnement du nouveau-né prématuré. Basée sur la Théorie de l’Attachement, la Théorie de la Participation Guidée et la Théorie Synactive du Développement, GP_Posit est principalement conçue afin de favoriser la sensibilité maternelle et le neurodéveloppement du nouveau-né prématuré. Ensuite, une étude pilote randomisée à deux groupes a été menée dans une USIN de niveau III d’un centre hospitalier universitaire mère-enfant. Au total, 20 dyades composées de mères et de leur nouveau-né prématuré ont été recrutées et randomisées au groupe expérimental (GP_Posit; n=10) ou au groupe contrôle (soins standards; n=10). Les résultats montrent que GP_Posit est faisable et acceptable pour les mères de nouveau-nés prématurés ainsi que pour l’équipe de recherche. Toutefois, au niveau de la faisabilité et l’acceptabilité du devis relatif à l’essai clinique randomisé, des difficultés ont été rencontrées au niveau du recrutement et la collecte de données au post-test. Les effets préliminaires estimés montrent une tendance vers un effet large indiquant une augmentation de la sensibilité maternelle chez les mères du groupe expérimental. Quant à l’effet préliminaire sur le neurodéveloppement, les nouveau-nés prématurés du groupe contrôle étaient légèrement favorisés. Une seconde étude pilote permettrait de mettre à l’essai des procédures modifiées de recrutement et collecte de données au post-test. Éventuellement, un essai contrôlé randomisé multicentrique à grande échelle permettra d’apprécier davantage les effets de GP_Posit sur la sensibilité maternelle et le neurodéveloppement des nouveau-nés prématurés. / Preterm infants are at risk of neurodevelopmental impairments which can manifest from infancy through adulthood. The early mother-infant relationship is one of the factors that can improve their neurodevelopment. The main component of this relationship is maternal sensitivity, that is the mother’s ability detect, interpret and respond in an appropriate and timely manner to her infant’s needs. However, due to the immaturity of preterm infants as well as the stress and anxiety experienced by mothers during hospitalization, they are at risk of developing suboptimal maternal sensitivity. Neonatal nurses play a key role and have the necessary skills to promote maternal sensitivity in the neonatal intensive care unit (NICU). However, the current evidence is neither sufficient nor of sufficiently good quality to guide the interventions that could be implemented by neonatal nurses to promote maternal sensitivity in the NICU. The aim of the thesis was twofold: 1- develop an innovative very early nursing intervention using an approach combining theory and empirical data to promote maternal sensitivity and neurodevelopment of preterm infants in the NICU; and 2- to implement and assess the feasibility, acceptability and estimate of the preliminary effects of this nursing intervention on maternal sensitivity and neurodevelopment of preterm infants in the NICU. A very early multifaceted nursing intervention named GP_Posit was developed. GP_Posit is a weekly individual intervention where nurses create a guided participation relationship with mothers, in a context of participation in care and positioning of the preterm infant. Based on Attachment Theory, Guided Participation Theory and Synactive Theory of Development, GP_Posit is primarily designed to promote maternal sensitivity and neurodevelopment of the preterm infant. A two-group randomized pilot study was conducted in a level III NICU of a mother-infant teaching hospital. A total of 20 dyads composed of mothers and preterm infants were recruited and randomized to the experimental group (GP_Posit; n = 10) or control group (standard care; n = 10). Results show that GP_Posit is feasible and acceptable for mothers of preterm infants as well as for the research team. Regarding the feasibility and acceptability of the randomized controlled trial study design, challenges were encountered in the recruitment and post-test data collection procedures. The preliminary effects showed a trend towards a large effect in increasing maternal sensitivity in experimental group mothers. As for the preliminary effect on neurodevelopment, preterm infants in the control group had an advantage. A second pilot study would be the opportunity to test modified recruitment and post-test data collection procedures. Eventually, a large-scale, multicenter randomized controlled trial would allow a better understanding of the effectiveness of GP_Posit on maternal sensitivity and preterm infant neurodevelopment.

Submitted by SBI Biblioteca Digital (sbi.bibliotecadigital@puc-campinas.edu.br) on 2017-04-07T19:37:44Z No. of bitstreams: 1 ELIZABETH BROWN VALLIM BRISOLA.pdf: 1755411 bytes, checksum: 14e7e25a069f401ef775a5d9ce3844f5 (MD5) / Made available in DSpace on 2017-04-07T19:37:44Z (GMT). No. of bitstreams: 1 ELIZABETH BROWN VALLIM BRISOLA.pdf: 1755411 bytes, checksum: 14e7e25a069f401ef775a5d9ce3844f5 (MD5) Previous issue date: 2017-02-14 / Research studies that address mothers singing focus on investigating how and why songs facilitate mother-infant communication considering, especially, the acoustical and sociocultural aspects involved. This qualitative and exploratory research study was developed based on Edmund Husserl?s phenomenology and guided by principles of Humanistic psychology, specifically Carl Roger?s Person Centered Approach. It aimed to apprehend the experience of 13 mothers who gave birth to their first child during the past 18 months, about the meaning of singing to their infants. The researcher spoke to each of the participants, all with a college education, during a dialogical encounter, and immediately afterwards wrote a comprehensive narrative to register her comprehension regarding that mother?s experience, based on her own impressions. A narrative-synthesis and a creative synthesis were constructed based on the narratives to enable a phenomenological process of analysis that presupposes three phases: description, comprehension and interpretation of the experience. The structural elements that emerged from the mothers' experience of singing to their infants are: (a) a means of communication hugging their infant with their song; (b) the establishment of an emotional bond with their infant; (c) a way to better know their infant as it develops; (d) a means of recognizing themselves as mothers; (e) a form of sharing personal values and family customs; (f) a creative way of expressing themselves, and (g) a possibility of personal growth. The meaning of this experience enables further reflections regarding human relationships from a psychological viewpoint and can stimulate dialogues with other areas of knowledge. / Las pesquisas que abordan el canto materno se preocupan en investigar c?mo y por qu? las canciones son facilitadoras de la comunicaci?n madre-beb?, dando atenci?n principalmente a los aspectos ac?sticos y socioculturales. Esta pesquisa, cualitativa y de naturaleza exploratoria, fue desarrollada con base en la fenomenolog?a de Edmund Husserl y en orientaciones te?ricas de la psicolog?a humanista, m?s espec?ficamente del Enfoque Centrado en la Persona, de Carl Rogers. Su foco fue aprender de la experiencia de 13 madres que tuvieron su primer hijo en los ?ltimos 18 meses sobre el sentido de cantarle a su beb?. La investigadora convers? com cada participante, mujeres universitarias, durante un encuentro dial?gico, y escribi?, de inmediato, una narrativa comprensiva para registrar su comprensi?n sobre la experiencia de aquella madre a partir de sus propias impresiones. Una s?ntesisnarrativa y una s?ntesis creativa fueron construidas a partir del conjunto de narrativas de manera que sea posible concluir el proceso de an?lisis fenomenol?gico que supone tres fases: descripci?n, comprensi?n e interpretaci?n de la experiencia. Los elementos estructurales que emergieron de las vivencias de las madres sobre cantarles a sus beb?s son: (a) un modo de comunicarse abrazando al beb? con sus sonidos; (b) la construcci?n de un v?nculo; (c) una forma de conocer mejor a su beb? a medida que ?ste se desarrolla; (d) un reconocimiento de s? misma como madre; (e) una manera de transmitir valores personales y costumbres familiares; (f) un modo creativo de expresarse; e (g) la posibilidad de crecimiento personal. El sentido de esta experiencia posibilita nuevas reflexiones sobre el tema de la relaci?n humana en t?rminos psicol?gicos y puede estimular interlocuciones con otras ?reas de conocimiento. / As pesquisas que abordam o cantar materno preocupam-se em investigar como e por que as can??es s?o facilitadoras da comunica??o m?e-beb?, dando aten??o principalmente aos aspectos ac?sticos e socioculturais. Esta pesquisa, qualitativa e de natureza explorat?ria, foi desenvolvida com base na fenomenologia de Edmund Husserl e em norteadores te?ricos da psicologia humanista, mais especificamente da Abordagem Centrada na Pessoa, de Carl Rogers. Objetivou apreender a experi?ncia de 13 m?es que tiveram seu primeiro filho nos ?ltimos 18 meses sobre o sentido de cantar para seu beb?. A pesquisadora conversou com cada uma das participantes, todas com forma??o universit?ria, durante um encontro dial?gico, e escreveu, em seguida, uma narrativa compreensiva para registrar sua compreens?o sobre a experi?ncia daquela m?e a partir de suas pr?prias impress?es. Uma narrativa-s?ntese e uma s?ntese criativa foram constru?das a partir do conjunto de narrativas de forma a possibilitar concluir o processo de an?lise fenomenol?gica que sup?e tr?s fases: descri??o, compreens?o e interpreta??o da experi?ncia. Os elementos estruturais que emergiram das viv?ncias das m?es sobre cantar para seu beb? s?o: (a) um modo de comunicar-se abra?ando o beb? com seus sons; (b) a constru??o de um v?nculo; (c) uma forma de conhecer melhor seu beb? ? medida que ele se desenvolve; (d) um meio de reconhecer a si mesma como m?e; (e) uma maneira de transmitir valores pessoais e costumes familiares; (f) um modo criativo de expressar-se; e (g) a possibilidade de crescimento pessoal. O sentido desta experi?ncia possibilita novas reflex?es sobre o tema do relacionamento humano em termos psicol?gicos e pode estimular interlocu??es com outras ?reas de conhecimento.