"In this work, therefore, we specifically sought to explore individual and population-level trends in infant
and early child neurodevelopment. Analyses of cognitive development, assessed using Mullen Scales
of Early Learning [40], a population normed and clinically administered tool that assesses function
across the five primary domains of fine and gross motor control, visual reception, and expressive and
respective language via direct observation and performance, provides some of the first direct evidence
of the developmental impact of the COVID-19 pandemic."
"The Mullen Scales of Early Learning (MSEL) is a standardized assessment that is commonly used in clinical psychology as a developmental measure of cognitive development (Mullen, 1989, 1995). The MSEL is organized into 5 subscales: (a) gross motor, (b) fine motor, (c) visual reception (or non-verbal problem solving), (d) receptive language, and (e) expressive language. An early learning composite score can be derived from fine motor, visual reception, receptive language, and expressive language scales. For young children this early learning composite score is considered equivalent to a more traditional “IQ” score or a developmental standard score." (https://www.sciencedirect.com/topics/psychology/mullen-scale...)
It's small wonder <2yo children born into this atmosphere would have underdeveloped receptive and expressive language skills.
I doubt this will prove an accurate measurement of their general cognitive development over time. Once the children are exposed to unmasked people with the frequency that used to be considered normal, their skills in that area will probably catch up...assuming what was previously considered "normal" ever does return.
https://www.pearsonassessments.com/store/usassessments/en/St...
"The Mullen Scales of Early Learning (MSEL) is a standardized assessment that is commonly used in clinical psychology as a developmental measure of cognitive development (Mullen, 1989, 1995). The MSEL is organized into 5 subscales: (a) gross motor, (b) fine motor, (c) visual reception (or non-verbal problem solving), (d) receptive language, and (e) expressive language. An early learning composite score can be derived from fine motor, visual reception, receptive language, and expressive language scales. For young children this early learning composite score is considered equivalent to a more traditional “IQ” score or a developmental standard score." (https://www.sciencedirect.com/topics/psychology/mullen-scale...)