The quality of parenting in reproductive donation families: A meta-analysis and systematic review.

This review examined whether the absence of a genetic link with one or both parents in families using reproductive donation induced a different quality of parenting from that found in families with spontaneous conception or autologous assisted reproductive technology (AUT-ART), where the genetic mother carries the pregnancy and both parents have a genetic link with their children. MEDLINE, PsycINFO and PubMed were searched for English-language studies published from January 1993 to October 2021. A total of 45 studies were included in the systematic review, and 11 in the meta-analysis. The meta-analysis showed that in reproductive donation families, where there was no genetic link between parents and children, there were higher positive parental values (P = 0.007) and lower negative parental values (P = 0.007) than for parents and children in families that had spontaneously conceived. No statistically significant differences emerged when the reproductive donation families were compared with the AUT-ART families. The study showed that the quality of parenting was not conditioned by the presence or absence of a genetic link; instead, it was influenced by the processes underlying family building, such as the desire to have a child, the involvement of both parents in the childcare and the quality of disclosure.

Stuttering as a matter of delay in neural activation: A combined TMS/EEG study.

OBJECTIVE: Brain dynamics in developmental stuttering (DS) are not well understood. The supplementary motor area (SMA) plays a crucial role, since it communicates with regions related to planning/execution of movements, and with sub-cortical regions involved in paced/voluntary acts (such as speech). We used TMS combined with EEG to shed light on connections in DS, stimulating the SMA. METHODS: TMS/EEG was recorded in adult DS and fluent speakers (FS), stimulating the SMA during rest. TMS-evoked potentials and source distribution were evaluated. RESULTS: Compared to FS, stutterers showed lower activity of neural sources in early time windows: 66-82 ms in SMA, and 91-102 ms in the left inferior frontal cortex and left inferior parietal lobule. Stutterers, however, showed higher activations in later time windows (i.e. from 260-460 ms), in temporal/premotor regions of the right hemisphere. CONCLUSIONS: These findings represent the functional counterpart to known white matter and cortico-basal-thalamo-cortical abnormalities in DS. They also explain how white matter abnormalities and cortico-basal-thalamo-cortical dysfunctions may be associated in DS. Finally, a mechanism is proposed in which compensatory activity of the non-dominant (right) hemisphere is recruited. SIGNIFICANCE: DS may be a disorder of neural timing that appears to be delayed compared to FS; new mechanisms that support stuttering symptoms are inferred; the SMA may be a promising target for neuro-rehabilitation.