scholarly journals A Computational Role for Top–Down Modulation from Frontal Cortex in Infancy

2020 ◽  
Vol 32 (3) ◽  
pp. 508-514 ◽  
Author(s):  
Sagi Jaffe-Dax ◽  
Alex M. Boldin ◽  
Nathaniel D. Daw ◽  
Lauren L. Emberson

Recent findings have shown that full-term infants engage in top–down sensory prediction, and these predictions are impaired as a result of premature birth. Here, we use an associative learning model to uncover the neuroanatomical origins and computational nature of this top–down signal. Infants were exposed to a probabilistic audiovisual association. We find that both groups (full term, preterm) have a comparable stimulus-related response in sensory and frontal lobes and track prediction error in their frontal lobes. However, preterm infants differ from their full-term peers in weaker tracking of prediction error in sensory regions. We infer that top–down signals from the frontal lobe to the sensory regions carry information about prediction error. Using computational learning models and comparing neuroimaging results from full-term and preterm infants, we have uncovered the computational content of top–down signals in young infants when they are engaged in a probabilistic associative learning.

1989 ◽  
Vol 66 (3) ◽  
pp. 1164-1171 ◽  
Author(s):  
D. L. Pickens ◽  
G. L. Schefft ◽  
B. T. Thach

We sought to characterize ventilatory and airway protective responses to pharyngeal stimulation in young infants during sleep. We studied the various responses with respect to frequency of occurrence, effect of increased stimulus intensity, and relation of stimulus fluid to laryngeal structures. Two groups of infants were studied: healthy full-term infants (n = 5) and preterm infants with a history of prolonged apnea (n = 9). We used a nasopharyngeal catheter to deliver small boluses of warm saline (0.02–0.35 ml) to the oropharynx. Responses repeatedly observed in both infant groups included swallows, obstructed respiratory efforts, brief apnea, prolonged apnea, and cough. In both infant groups, swallows and obstructed breaths occurred frequently and cough and prolonged apnea infrequently. The functional significance of some response patterns was clear, whereas that of others was obscure. Larger stimulus volumes yielded more frequent responses (P less than 0.01), and preterm infants responded much more frequently than full-term infants (P less than 0.01). Prolonged apnea was a composite of the other responses and was much more common in preterm than full-term infants (P less than 0.01). The stimulus technique was performed under direct visualization of the airway in two deceased infants. The findings suggested that the relation of the piriform fossae to the interarytenoid notch is important in determining response frequency. Implications for regulation of the removal of upper airway secretions during sleep are discussed.


Author(s):  
Ruediger Kissgen ◽  
Sebastian Franke ◽  
Nino Jorjadze ◽  
Bernhard Roth ◽  
Angela Kribs

This study examines the infant–father attachment in infants born preterm (<  1500 g at birth and/or <  37 weeks gestation) in comparison to full-term infants. The infant–father attachment was assessed using the Strange Situation Procedure at a (corrected) age of 15 months. We found at least half of preterm and full-term infants (50.0% and 56.5 % respectively) securely attached to their fathers, and no significant overall difference was observed concerning the distribution of attachment quality comparing the two groups. In light of the fact that preterm infants tend to have numerous neurodevelopmental problems, it is encouraging that significant differences were not found in the distribution of the attachment quality among the groups. Therefore, from the perspective of attachment research, it would be highly beneficial to include fathers in the care of their preterm infants.


PEDIATRICS ◽  
1995 ◽  
Vol 96 (1) ◽  
pp. 64-68
Author(s):  
J. Groswasser ◽  
M. Sottiaux ◽  
E. Rebuffat ◽  
T. Simon ◽  
M. Vandeweyer ◽  
...  

Objective. To investigate the effect of body rocking on infant respiratory behavior during sleep. Methods. Eighteen infants with documented obstructive sleep apneas were studied. There were eight premature infants with persistent bradycardias and 10 infants born full-term, admitted after an idiopathic apparent life-threatening event. No cause for the obstructive apneas was found. The infants were recorded with polygraphic techniques during two successive nights. They were randomly assigned to a rocking or a nonrocking mattress. The conditions were reversed the following night, in a crossover design. Results. In both groups of infants, no significant difference was seen between the two consecutive nights for most of the variables studied: total sleep time, the proportion of non-rapid-eye-movement and rapid-eye-movement sleep, the number of arousals, the number and maximal duration of central apneas, the frequency of periodic breathing, the level of oxygen saturation, and heart rate. During the nonrocking nights, all infants had repeated obstructive breathing events. In seven of the eight preterm infants and in nine of the 10 full-term subjects, body rocking was associated with a significant decrease in the frequency of obstructive events. During rocking, in the preterm infants the obstructions fell from a median of 2.5 to 1.8 episodes per hour (P = .034). In the full-term infants, rocking reduced the obstructive events from a median of 1.5 obstructions per hour to 0.7 (P = .005). No difference was seen for the duration of the obstructive episodes. Conclusion. In preterm and full-term infants prone to obstructive sleep apneas, gentle side-to-side body rocking is associated with a significant decrease in the frequency of upper-airway obstructions.


2020 ◽  
Vol 16 (2) ◽  
pp. 148-155
Author(s):  
Areti Aphrodite Sioriki ◽  
Despoina Gkentzi ◽  
Evangelia Papadimitriou ◽  
Gabriel Dimitriou ◽  
Ageliki Karatza

Infants born prematurely (before completion of 37 weeks of gestation) are at increased risk of morbidity and mortality due to vaccine preventable diseases, mostly because of their immunological immaturity and failure of transfer of maternal protective antibodies. Despite their great need of being vaccinated, concerns on vaccine safety and efficacy, constitute the main reasons for which vaccinations are often delayed in this group. In this review we summarize the latest evidence on vaccine safety, efficacy and immunogenicity in preterm infants which is similar to full-term infants. Therefore there is no reason for delaying vaccination in this population.


2017 ◽  
Vol 123 (6) ◽  
pp. 1563-1570 ◽  
Author(s):  
Sotirios Fouzas ◽  
Ilias Theodorakopoulos ◽  
Edgar Delgado-Eckert ◽  
Philipp Latzin ◽  
Urs Frey

The concept of diffusional screening implies that breath-to-breath variations in CO2 clearance, when related to the variability of breathing, may contain information on the quality and utilization of the available alveolar surface. We explored the validity of the above hypothesis in a cohort of young infants of comparable postmenstrual age but born at different stages of lung maturity, namely, in term-born infants ( n = 128), preterm-born infants without chronic lung disease of infancy (CLDI; n = 53), and preterm infants with moderate/severe CLDI ( n = 87). Exhaled CO2 volume (VE,CO2) and concentration (FE,CO2) were determined by volumetric capnography, whereas their variance was assessed by linear and nonlinear variability metrics. The relationship between relative breath-to-breath change of VE,CO2 (ΔVE,CO2) and the corresponding change of tidal volume (ΔVT) was also analyzed. Nonlinear FE,CO2 variability was lower in CLDI compared with term and non-CLDI preterm group ( P < 0.001 for both comparisons). In CLDI infants, most of the VE,CO2 variability was attributed to the variability of VT ( r2 = 0.749), whereas in term and healthy preterm infants this relationship was weaker ( r2 = 0.507 and 0.630, respectively). The ΔVE,CO2 − ΔVT slope was less steep in the CLDI group (1.06 ± 0.07) compared with non-CLDI preterm (1.16 ± 0.07; P < 0.001) and term infants (1.20 ± 0.10; P < 0.001), suggesting that the more dysmature the infant lung, the less efficiently it eliminates CO2 under tidal breathing conditions. We conclude that the temporal variation of CO2 clearance may be related to the degree of lung dysmaturity in early infancy. NEW & NOTEWORTHY Young infants exhibit appreciable breath-to-breath CO2 variability that can be quantified by nonlinear variability metrics and may reflect the degree of lung dysmaturity. In infants with moderate/severe chronic lung disease of infancy (CLDI), the variability of the exhaled CO2 is mainly driven by the variability of breathing, whereas in term-born and healthy preterm infants this relationship is less strong. The slope of the relative CO2-to-volume change is less steep in CLDI infants, suggesting that dysmature lungs are less efficient in eliminating CO2 under tidal breathing conditions.


2019 ◽  
Vol 109 (5) ◽  
pp. 1353-1360 ◽  
Author(s):  
Tom Norris ◽  
Sara E Ramel ◽  
Patrick Catalano ◽  
Carol ni Caoimh ◽  
Paola Roggero ◽  
...  

ABSTRACT Background Air-displacement plethysmography (ADP) is a good candidate for monitoring body composition in newborns and young infants, but reference centile curves are lacking that allow for assessment at birth and across the first 6 mo of life. Objective Using pooled data from 4 studies, we aimed to produce new charts for assessment according to gestational age at birth (30 + 1 to 41 + 6 wk) and postnatal age at measurement (1–27 wk). Methods The sample comprised 222 preterm infants born in the United States who were measured at birth; 1029 term infants born in Ireland who were measured at birth; and 149 term infants born in the United States and 57 term infants born in Italy who were measured at birth, 1 and 2 wk, and 1, 2, 3, 4, 5, and 6 mo of age. Infants whose birth weights were <3rd or >97th centile of the INTERGROWTH-21st standard were excluded, thereby ensuring that the charts depict body composition of infants whose birth weights did not indicate suboptimal fetal growth. Sex-specific centiles for fat mass (kg), fat-free mass (kg), and percentage body fat were estimated using the lambda-mu-sigma (LMS) method. Results For each sex and measure (e.g., fat mass), the new charts comprised 2 panels. The first showed centiles according to gestational age, allowing term infants to be assessed at birth and preterm infants to be monitored until they reached term. The second showed centiles according to postnatal age, allowing all infants to be monitored to age 27 wk. The LMS values underlying the charts were presented, enabling researchers and clinicians to convert measurements to centiles and z scores. Conclusions The new charts provide a single tool for the assessment of body composition, according to ADP, in infants across the first 6 mo of life and will help enhance early-life nutritional management.


Hematology ◽  
2012 ◽  
Vol 2012 (1) ◽  
pp. 506-511 ◽  
Author(s):  
Martha Sola-Visner

Abstract Thrombocytopenia is a common problem among sick neonates admitted to the neonatal intensive care unit. Frequently, platelet transfusions are given to thrombocytopenic infants in an attempt to decrease the incidence or severity of hemorrhage, which is often intracranial. Whereas there is very limited evidence to guide platelet transfusion practices in this population, preterm infants in the first week of life (the highest risk period for bleeding) are nearly universally transfused at higher platelet counts than older infants or children. To a large extent, this practice has been influenced by the observation that neonatal platelets are hyporeactive in response to multiple agonists in vitro, although full-term infants exhibit normal to increased primary hemostasis. This apparently paradoxical finding is due to factors in the neonatal blood that enhance the platelet-vessel wall interaction and counteract the platelet hyporeactivity. Relatively few studies have evaluated the platelet function and primary hemostasis of preterm infants, the subset of neonates at highest risk of bleeding and those most frequently transfused. Current understanding of platelet production and function in preterm and full-term neonates, how these factors affect their response to thrombocytopenia and their primary hemostasis, and the implications of these developmental differences to transfusion medicine are reviewed herein.


1992 ◽  
Vol 73 (6) ◽  
pp. 2368-2372 ◽  
Author(s):  
S. Duara ◽  
G. Silva Neto ◽  
N. Claure ◽  
T. Gerhardt ◽  
E. Bancalari

The influence of maturation on extrathoracic airway (ETA) stability during quiet sleep was determined in 13 normal preterm infants of 1.41 +/- 0.14 (SD) kg birth weight and 32 +/- 2 wk estimated gestational age. Studies began in the first week of life and were performed three times at weekly intervals. A drop in intraluminal pressure within the ETA was produced by external inspiratory flow-resistive loading (60 cmH2O.l-1 x s at 1 l/min); an increase in intrinsic resistance, indicating airway narrowing, was sought as a measure of ETA instability. Baseline total pulmonary resistance was not significantly different between weeks 1, 2, and 3 (88 +/- 35, 65 +/- 24, and 61 +/- 17 cmH2O.l-1 x s, respectively) but increased markedly above baseline with loading to 144 +/- 45 cmH2O.l-1.s during week 1 (P < 0.001), 89 +/- 28 cmH2O.l-1 x s at week 2 (P < 0.01), and 74 +/- 25 cmH2O.l-1 x s at week 3 (n = 10). The increment with loading was significantly greater during week 1 than during weeks 2 or 3 (P < 0.02). Similar studies were also done in seven full-term infants in the first week of life to evaluate the influence of gestational maturity on ETA stability. Despite a relatively greater drop in intraluminal pressure within the ETA of term vs. preterm infants with loading (P < 0.001), total pulmonary resistance failed to increase (68 +/- 21 to 71 +/- 32 cmH2O.l-1.s). These data reveal that ETA instability is present in preterm infants at birth and decreases with increasing postnatal age. Full-term neonates, by comparison, display markedly greater ETA stability in the immediate neonatal period.


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