Using Functional Connectivity Magnetic Resonance Imaging to Measure Brain Connectivity in Preterm Infants

Effects of repetitive transcranial magnetic stimulation and their underlying neural mechanisms evaluated with magnetic resonance imaging-based brain connectivity network analyses

Repetitive transcranial magnetic stimulation (rTMS) is a noninvasive brain modulation and rehabilitation technique used in patients with neuropsychiatric diseases. rTMS can structurally remodel or functionally induce activities of specific cortical regions and has developed to an important therapeutic method in such patients. Magnetic resonance imaging (MRI) provides brain data that can be used as an explanation tool for the neural mechanisms underlying rTMS effects; brain alterations related to different functions or structures may be reflected in changes in the interaction and influence of brain connections within intrinsic specific networks. In this review, we discuss the technical details of rTMS and the biological interpretation of brain networks identified with MRI analyses, comprehensively summarize the neurobiological effects in rTMS-modulated individuals, and elaborate on changes in the brain network in patients with various neuropsychiatric diseases receiving rehabilitation treatment with rTMS. We conclude that brain connectivity network analysis based on MRI can reflect alterations in functional and structural connectivity networks comprising adjacent and separated brain regions related to stimulation sites, thus reflecting the occurrence of intrinsic functional integration and neuroplasticity. Therefore, MRI is a valuable tool for understanding the neural mechanisms of rTMS and practically tailoring treatment plans for patients with neuropsychiatric diseases.

Effect of Tactile Experience During Preterm Infant Feeding on Clinical Outcomes

BACKGROUND

Although the survival rate of very preterm infants has improved, rates of subsequent neurobehavioral disabilities remain high. One factor implicated in poor neurobehavioral and developmental outcomes is hospitalization and inconsistent caregiving patterns in the neonatal intensive care unit. Although much underlying brain damage occurs in utero or shortly after birth, neuroprotective strategies may stop progression of damage, particularly when these strategies are used during the most sensitive periods of neural plasticity 2-3 months before term age.

OBJECTIVE

The purpose of this analysis was to test the effect of a patterned feeding experience involving a tactile component (touch and/or holding) provided during feedings on preterm infants' clinical outcomes, measured by oral feeding progress, as an early indicator of neurodevelopment.

METHODS

We used an experimental, longitudinal, two-group random assignment design. Preterm infants (n = 120) were enrolled within the first week of life and randomized to an experimental group receiving a patterned feeding experience or to a control group receiving usual feeding care.

RESULTS

Analysis of data from 91 infants showed that infants receiving touch at more than 25% of early gavage feedings achieved full oral feeding more quickly; as touch exposure increased, time from first oral to full oral feeding decreased. There was no association between holding during early gavage feedings or touch during transition feedings and time to full oral feeding.

DISCUSSION

Neurological expectation during critical periods of development is important for infants. However, a preterm infant's environment is not predictable: Caregivers change regularly, medical procedures dictate touch and holding, and care provision based on infant cues is limited. Current knowledge supports caregiving that occurs with a naturally occurring sensation (i.e., hunger), is provided in a manner that is congruent with the expectation of the neurological system, and occurs with enough regularity to enhance neuronal and synaptic development. In this study, we modeled an experience infants would "expect" if they were not in the neonatal intensive care unit and demonstrated a shorter time from first oral feeding to full oral feeding, an important clinical outcome with neurodevelopmental implications. We recommend further research to determine the effect of patterned caregiving experiences on other areas of neurodevelopment, particularly those that may occur later in life.