Question

According to our test, scientist have discovered based on equipment like fMRI that babies think before they talk.

how do these findings impact how we should approach interaction with babies

Answer 1

-These functional magnetic resonance imaging (fMRI) studies make great stories. If you give a TED talk, I believe they’re legally required. Still no place is darker than inside our heads. The images don’t actually measure brain activity; they detect blood flow. That flow makes an image light up. The approach is predicated on the idea that blood flow couples with brain activity. That leap is made, aptly, in our own brains, where we collectively assume that the areas getting a lot of blood flow are working harder.

Recent studies have called that foundational assumption to question, including a unique approach today in the Journal of Neuroscience, where a team at Columbia University's Zuckerman Institute released findings that upend the traditional fMRI model for young brains. Adult responses do not occur in newborn brains, the researchers found: Brain cells fire, but blood flow does not increase. Coupling happens later. This could explain why fMRI is unpredictable in human infants and, more importantly, challenge the idea that blood flow coupling is the foundation of brain development.

- In babies, there seem to be implications here for older people with conditions that result from oxygen deprivation—strokes and cerebral vascular disease as well.Hillman’s hypothetical explanation comes from her own children, remembering that as toddlers, they would run themselves into the ground until they were so hungry they couldn't function,“and then you have to stuff goldfish crackers in their mouth. I see a lot of analogies in the brain. The newborn brain is sort of caught by surprise where neural activity happens and it doesn't have a blood-flow response there ready and waiting to stop the brain from running out of oxygen. I have this sort of weird little anthropomorphic interpretation, where the brain is sort of figuring it out as it develops. Interacting with your baby and responding to their cues will help their emotional wellbeing. Talk to your baby, play with them, tell them rhymes and sing them songs. Give your baby a break when their expression, voice or movements change as they may be getting tired.

-The use of fMRI methods with infants and toddlers in research settings is a relatively recent phenomenon :

Collecting high quality MR images typically requires a participant to remain still throughout one or more scans, lasting 4–8 min on average. In childhood including children as young as 4 years-of-age and beyond, this is accomplished by providing instructions, practice and incentives. For infants, this is not an option.
Early on this barrier was overcome with the use of sedation, which relegated scanning to clinical settings, and likely produced blunted functional responses. Several researchers then pioneered the technique of conducting fMRI scans with infants during natural sleep

- The two forms of functional MRI employed in infant studies are task-based fMRI and rs-fcMRI in babies. While both methods are based on the Blood Oxygen Level Dependent (BOLD) signal, they allow for examining two critical aspects of healthy brain functioning. Task-based fMRI facilitates examination of the brain's response to specific aspects of the environment, including cues known to be important for infant development. These include tactile stimulation, and smells or sounds associated with caregivers.
Rs-fcMRI provides information about how the brain is intrinsically functionally organized. It is this organization, which likely allows for proper stimulus response, as well as complex mental processes necessary for cognitive, emotional and social functioning. Both of these methods rely on the capacity of fMRI to index brain functioning in specific cortical and subcortical regions throughout the brain. In Section 1.4, we will highlight the unique advantages of fMRI in the context of other functional neuroimagingtechniques employed in developmental research.

- Task-based fMRI with infants and toddlers

Implementing task-based fMRI with infants is unquestionably challenging. It requires infants to sleep through the excessive noise of the MRI during data acquisition, as well as the sensory stimulation of the paradigm. Despite these challenges, nine studies successfully using this methodology with participants ranging from seven days postnatal to
four years-of-age have now been reported. The sample sizes and findings reported in these studies indicate the feasibility of using this methodology with infants and toddlersto collect adequate amounts of data to address study aims. Beyond the feasibility of data collection, another important issue is whether sleeping infants process stimuli
presented during task-based paradigms, and whether they do so in a manner captured by BOLD fMRI. Auditory stimuli are most commonly used in infant fMRI research. Positive BOLD response in sleeping infants and toddlers has been observed in auditory processing brain region in response to tones, nonvocal naturalistic sounds, vocal sounds and speech. However, it appears that this response may be decreased from baseline in very young infants during presentation of non-naturalistic stimuli. In addition to basic sensory processing of auditory stimuli, research to date provides evidence for differentiation between distinct types of auditory stimuli during natural sleep. Redcay and colleagues reported distinct patterns of brain activation in sleeping toddlers (two to four years-old) during presentations of tones versus nonvocal naturalistic sounds or
vocal sounds. By establishing the capacity to characterize neural processing of stimuli at a basic sensory level, this work provides a foundation for using natural sleep fMRI to examine additional aspects of stimulus processing.

- Several studies have demonstrated the utility of natural sleep fMRI for examining early language and emotion processing. Patterns of brain activation in sleeping infants indicate registration of speech and vocal properties. For example, Dehaene-Lambertz and colleagues (2002) observed greater activation in the left angular gyrus and precuneus in response to forward versus backward speech in sleeping two to three month-old infants. In adults, these regions have been associated with differentiating between words andnon-words and with memory retrieval of verbal information respectively. These results were replicated in a study of two year-old children during natural sleep, which further identified developmental changes in speech processing from two to three years-of-age. In comparison to two year-olds, three year-olds demonstrate greater engagement of brain regions in line with speech processing in adults, such as the superior temporal gyrus, in response to forward versus backward speech. Recent findings also indicate differential brain processing of vocal non-speech sounds (e.g. crying or laughing) based on emotion category for three to seven month-old infants during natural sleep. Specifically, during sad versus neutral vocalizations, infants demonstrate greater activation in the insula and part of the orbitofrontal cortex. These studies indicate the capacity for natural sleep fMRI to lead to increased understanding of how the brain processes language and emotion beginning in infancy. An important consideration for fMRI with sleeping infants was raised by Dehaene-Lambertz and colleagues (2010) in their examination of BOLD responses to sensory stimuli on an individual subject level. The authors
reported that less than half of sleeping two-month-old infants in their sample demonstrated activation in auditory brain regions when contrasting stimulus presentation to no sound. They suggest that developmental characteristics of the BOLD signal at this early age may account for the lack of observed activation in auditory regions for some infants. However, there
are multiple factors that may influence whether or not a BOLD response is captured during acquisition. These factors might include sleep state, developmental stage, scanner noise and statistical power. Thus, it seems appropriate to consider this larger context when interpreting the presence or absence of activation within an individual subject. Including or excluding a subject based on the presence or absence of activity can only be considered in this context, and should be explained and justified.

- Resting state functional connectivity MRI with infants and toddlers

In contrast to task-based fMRI, rs-fcMRI allows for examination of intrinsic correlated brain activity in the absence of a specific task or external stimulus. Rs-fcMRI typically involves examining changes in brain signal over the course of a scan lasting between 5 and 10 min, or more. During the scan, older children and adult participants rest with eyes open or closed, while infants or toddler participants are asleep. Rs-fcMRI focuses on correlating fluctuations in the brain signal between a
region and all other voxels in the brain, or between specific brain regions. Low frequency changes in brain signal observed in the absence of stimuli presentation likely reflect endogenous neural activity. Correlations between spontaneous brain activity over time are posited to represent connectivity between brain regions. Recent findings provide support for this conceptualization, with patterns of functional connectivity frequently in line with direct or indirect structural connectivity between brain regions.

Rs-fcMRI data can be characterized at three levels of analysis (Churchland and Sejnowski, 1990). At the first level of analysis (circuit level), connections between brain regions are defined by the strength of the correlation between their signals. The second level of analysis characterizes functional brain networks as a whole instead of as individual connections within the system. Examples of functional brain networks that have been characterized with rs-fcMRI include the default network, a group of brain regions that demonstrate higher levels of activity in the absence of specific external tasks, and networks underlying specific aspects of cognitive control, such as the fronto-parietal and cingulo-opercular networks. The third level of analysis (global topology) focuses on interactions within and between functional networks. All three of these levels of analysis provide information about the functional organization of the brain that have been shown to be relevant to mental health and specific aspects of cognitive and emotional functioning.

- For developmental research, rs-fcMRI has the distinct advantage of documenting coordinated brain functioning across the whole brain in the absence of tasks, which are challenging to adjust appropriately for a wide age range. Moreover, research with adults has indicated that while a particular paradigm employed in task-based fMRI may only activate a subset of regions involved in a broad domain of functioning, such as memory, rs-fcMRI can yield a more complete representation of the network of brain regions involved. This is particularly relevant for infant fMRI. Because scans are conducted during natural sleep, there are even more limitations on the types of stimuli and tasks that can be used in the scanner, decreasing the chances of activating the full set of regions involved in a behavioral domain of interest. Investigations using rs-fcMRI have indicated the utility of this methodology for studying the functional development of brain networks across a wide age range. For example, several reports have documented a pattern of developmental changes in the functional connectivity of brain networks from childhood to adulthood that is characterized by increasing long-range connectivity (between anatomically distant regions) and decreasing short-range (or localized) connectivity. A similar pattern has been observed across the first two years-of-life.
Changes across this earlier age range occur at an extremely rapid rate, such that from two-weeks to one year-of-age, the number of regions overlapping with the adult default network that evidence significant functional connectivity during natural sleep increases from six to thirteen. Development does not appear to be linear, with many measures indicating less change across the second year-of-life in comparison.