Literature Review: Behavioral Assessment of Interhemispheric Connection in School-Aged Children

from docx import Document
from docx.shared import Pt, Inches, RGBColor
from docx.enum.text import WD_ALIGN_PARAGRAPH
from docx.oxml.ns import qn
from docx.oxml import OxmlElement

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# TITLE BLOCK
# =========================================================
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r = title_p.add_run("Behavioral Assessment of Interhemispheric Connection in School-Aged Children: A Literature Review")
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doc.add_paragraph()  # blank line

# =========================================================
# ABSTRACT
# =========================================================
add_heading_para("Abstract", level=1)

abstract_text = (
    "The corpus callosum (CC) is the principal white matter commissure mediating interhemispheric "
    "communication and is central to a broad range of sensorimotor, cognitive, and linguistic "
    "functions. School-aged children (6-12 years) undergo intensive callosal myelination and "
    "axonal pruning during which behavioral indicators of interhemispheric transfer are rapidly "
    "evolving. This review synthesizes evidence on behavioral methods used to assess interhemispheric "
    "connection in this age group, including bimanual coordination tasks, interhemispheric transfer "
    "time (IHTT) paradigms, and dichotic listening. Drawing on the foundational framework of "
    "Gooijers and Swinnen (2014), the review discusses the CC's dual inhibitory-decoupling and "
    "coordinative-coupling roles, regional topographic contributions, and key mediating factors "
    "such as age, sex, handedness, clinical pathology, and training. Methodological limitations "
    "of purely behavioral IHTT measures in young children are highlighted, and directions for "
    "future research are proposed."
)
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r1 = kw_p.add_run("Keywords: ")
set_font(r1, bold=True)
r2 = kw_p.add_run(
    "corpus callosum, interhemispheric transfer, bimanual coordination, school-aged children, "
    "behavioral assessment, laterality, dichotic listening, motor development"
)
set_font(r2, italic=True)

# =========================================================
# SECTION 1 — INTRODUCTION
# =========================================================
add_heading_para("1. Introduction", level=2)

add_body(
    "The two cerebral hemispheres, though anatomically distinct, function as an integrated unit "
    "for most complex behavioral tasks. The corpus callosum (CC), comprising approximately 200-800 "
    "million axonal fibers, serves as the primary structural substrate for interhemispheric "
    "communication (Gooijers & Swinnen, 2014). In their seminal review, Gooijers and Swinnen "
    "established that the CC is not a passive conduit but actively mediates the degree of functional "
    "coupling between hemispheres, with its microstructural properties predicting behavioral "
    "performance on tasks requiring inter-limb and cross-modal coordination."
)
add_body(
    "For school-aged children (approximately 6-12 years), this period represents a window of "
    "intensive callosal myelination and axonal pruning during which interhemispheric communication "
    "undergoes rapid and measurable refinement (Meissner et al., 2017). Studying this maturation "
    "through behavioral methods offers practical advantages: behavioral tasks are non-invasive, "
    "ecologically valid, sensitive to developmental change, and feasible in school or clinical "
    "settings without specialized neuroimaging infrastructure. The present review synthesizes the "
    "theoretical and empirical basis for behavioral assessment of interhemispheric connection in "
    "this population, discusses key mediating factors, and identifies gaps warranting future research."
)

# =========================================================
# SECTION 2 — CORPUS CALLOSUM: ANATOMY AND DEVELOPMENT
# =========================================================
add_heading_para("2. Corpus Callosum: Anatomy and Developmental Trajectory", level=2)

add_body(
    "The CC is conventionally divided into five subregions: rostrum, genu, body (anterior, mid, "
    "and posterior), isthmus, and splenium. These subregions carry fibers from distinct cortical "
    "areas in an anterior-to-posterior topographic arrangement: the genu transmits prefrontal "
    "fibers, the body transmits premotor and motor fibers, and the splenium transmits parietal, "
    "temporal, and occipital fibers (Witelson, 1989, as cited in Gooijers & Swinnen, 2014). "
    "This regional organization is functionally significant because it predicts which behavioral "
    "domains are selectively affected by regional callosal disruption or developmental delay."
)
add_body(
    "Myelination of the CC follows a prolonged postnatal trajectory. While the genu undergoes "
    "substantial myelination during the first two years of life, the posterior body, isthmus, "
    "and splenium continue to mature through adolescence and into early adulthood (Lebel et al., "
    "2008). Diffusion tensor imaging (DTI) studies consistently demonstrate that fractional "
    "anisotropy (FA) increases throughout childhood and adolescence, while mean diffusivity (MD) "
    "and radial diffusivity (RD) decline (Chaddock-Heyman et al., 2018). This prolonged "
    "maturation is reflected in the gradual improvement of behavioral measures of interhemispheric "
    "transfer across the school years."
)

# =========================================================
# SECTION 3 — BEHAVIORAL MEASURES
# =========================================================
add_heading_para("3. Behavioral Measures of Interhemispheric Connection", level=2)

add_heading_para("3.1 Interhemispheric Transfer Time: The Poffenberger Paradigm", level=3)

add_body(
    "The most widely used behavioral measure of CC function is interhemispheric transfer time "
    "(IHTT), estimated via the crossed-uncrossed difference (CUD) in simple reaction time. In "
    "the Poffenberger paradigm, a unilateral visual stimulus is presented to one hemifield and "
    "reaction time is recorded for ipsilateral versus contralateral hand responses. The CUD - "
    "the arithmetic difference between crossed and uncrossed reaction times - provides an estimate "
    "of axonal conduction velocity through the CC (Gooijers & Swinnen, 2014)."
)
add_body(
    "Meissner et al. (2017) directly tracked callosal maturation in 7-year-old children using "
    "both behavioral and electrophysiological CUDs. Electrophysiological CUDs were significantly "
    "faster in adults than in 7-year-olds, confirming ongoing callosal development; however, "
    "behavioral CUDs did not significantly differ between groups and proved unreliable at "
    "6-month retest. This dissociation indicates that behavioral IHTT measures may be "
    "insufficiently sensitive to capture callosal immaturity in younger school-aged children, "
    "a key methodological caveat when designing purely behavioral assessment batteries."
)

add_heading_para("3.2 Bimanual Coordination Tasks", level=3)

add_body(
    "Gooijers and Swinnen (2014) provided the most comprehensive synthesis of the CC-bimanual "
    "coordination relationship, identifying two complementary callosal roles: (1) an "
    "inhibitory-decoupling role that permits the hands to perform asymmetric movements by "
    "suppressing unintended mirror activity, and (2) a coordinative-coupling role that "
    "synchronizes the timing of symmetric or rhythmically related bimanual movements. "
    "Evidence for the inhibitory-decoupling function comes from split-brain (callosotomy) "
    "patients, who show paradoxical improvement in hand independence after CC section but "
    "profound deficits in acquiring new asymmetric bimanual skills. The coordinative function "
    "is supported by consistent DTI findings in which higher FA in the callosal body predicts "
    "better bimanual timing accuracy and lower phase error."
)
add_body(
    "In children, Hung et al. (2019) examined 39 children (aged 6-17 years) with unilateral "
    "spastic cerebral palsy using DTI and a kinematic bimanual drawer-opening task. Axial "
    "diffusivity of the whole CC predicted total movement time and goal synchronization overlap, "
    "while splenium integrity specifically predicted temporal coordination. This regional "
    "specificity - consistent with the Gooijers-Swinnen framework - confirms that behavioral "
    "bimanual tasks can serve as valid functional correlates of callosal integrity in "
    "school-aged pediatric populations."
)
add_body(
    "Azatyan (2023) assessed interhemispheric interaction in 73 school-aged children (8-11 "
    "years) using bimanual motor and reciprocal coordination tests. Reciprocal coordination "
    "disorders were detected in 41% of participants, predominantly manifesting as left-hand "
    "failures or lag. The degree of interhemispheric interaction formation correlated "
    "significantly with spatial representations, and patterns differed by age subgroup (8-9 vs. "
    "10-11 years), sex, and manual preference. These findings provide empirical developmental "
    "staging for school-based behavioral assessment and confirm that the 8-9 year window marks "
    "stabilization of main motor-sensory asymmetries, while 10-11 years consolidates an "
    "individual interhemispheric interaction modus."
)

add_heading_para("3.3 Dichotic Listening", level=3)

add_body(
    "Dichotic listening (DL) tasks present competing auditory stimuli simultaneously to each ear. "
    "The typical right-ear advantage (REA) in right-handed individuals reflects left-hemispheric "
    "dominance for speech and interhemispheric relay of the left-ear signal via the splenium and "
    "posterior commissural fibers, making DL an indirect behavioral index of both auditory "
    "lateralization and posterior callosal integrity (Gooijers & Swinnen, 2014)."
)
add_body(
    "Bradley et al. (2024) examined dichotic listening and CC structure in individuals with spina "
    "bifida myelomeningocele, a condition with characteristic posterior callosal hypoplasia. "
    "Although both groups showed a normative REA, fewer participants with splenium hypogenesis "
    "or severe posterior hypoplasia exhibited this advantage, confirming that the behavioral "
    "dichotic laterality depends on intact posterior callosal pathways. The anterior commissure "
    "was identified as a potential compensatory pathway. Stipdonk et al. (2022) extended this "
    "evidence to very preterm children, demonstrating that DL lateralization correlated with "
    "interhemispheric structural connectivity and language performance, strengthening the case "
    "for DL as a valid behavioral correlate of callosal function in school-aged populations "
    "with and without developmental complications."
)

# =========================================================
# SECTION 4 — MEDIATING FACTORS
# =========================================================
add_heading_para("4. Mediating Factors in the Corpus Callosum-Behavior Relationship", level=2)

add_heading_para("4.1 Age and Maturation", level=3)

add_body(
    "Age is the primary factor moderating the CC-behavior relationship in school-aged children. "
    "Gooijers and Swinnen (2014) noted that the brain-behavior link is strongest at the extremes "
    "of the maturational spectrum. In school-aged children, the motor body of the CC continues "
    "to mature, reflected in progressive reduction of IHTT and refinement of bimanual timing from "
    "ages 6 to 12 (Meissner et al., 2017). Any behavioral assessment protocol must account for "
    "this variability through age-stratified normative comparisons with yearly intervals."
)

add_heading_para("4.2 Handedness and Laterality", level=3)

add_body(
    "Handedness significantly modulates callosal organization and the interpretation of behavioral "
    "laterality measures. Witelson (1989) reported sex and handedness differences in isthmus and "
    "genu morphology. Azatyan (2023) found that manual preference significantly influenced both "
    "interhemispheric interaction formation and spatial representation performance in school-aged "
    "children, with left-handed and ambidextrous children showing greater variability in callosal "
    "function. Bortoletto et al. (2021) further demonstrated in adults that asymmetric "
    "transcallosal conduction delay - differing latencies for right-to-left versus left-to-right "
    "hemisphere transfer - was the strongest predictor of bimanual coordination quality, "
    "challenging the assumption that shorter transfer times are uniformly advantageous. "
    "This directionality consideration has direct implications for pediatric behavioral "
    "test designs, which should evaluate separately hand-initiated and side-specific conditions."
)

add_heading_para("4.3 Pathology", level=3)

add_body(
    "Several pediatric clinical populations provide important behavioral validation data. "
    "Dennis et al. (2015) showed in pediatric traumatic brain injury (TBI) that behavioral "
    "and electrophysiological IHTT segregated patients into those with and without callosal "
    "dysfunction; the impaired IHTT group demonstrated lower FA, higher MD on DTI, and "
    "significantly poorer neurocognitive composite scores, confirming behavioral IHTT as a "
    "clinically meaningful endpoint in acquired childhood brain injury. In children with "
    "unilateral spastic cerebral palsy, Weinstein et al. (2014) demonstrated that poorer "
    "CC integrity corresponded to more severe unimanual and bimanual clinical function, "
    "providing concurrent validity for behavioral bimanual assessments in this group."
)

add_heading_para("4.4 Training and Plasticity", level=3)

add_body(
    "Gooijers and Swinnen (2014) identified bimanual skill training as a mediating factor "
    "capable of producing measurable increases in CC microstructure FA in regions corresponding "
    "to trained task demands in adults. Weinstein et al. (2015) provided preliminary evidence "
    "for training-induced callosal plasticity in children with hemiparesis following intensive "
    "bimanual therapy. These findings position behavioral bimanual assessments as sensitive "
    "outcome measures in longitudinal intervention studies, where callosal behavioral metrics "
    "can serve as proxies for training-induced structural plasticity."
)

# =========================================================
# SECTION 5 — ASSESSMENT BATTERY
# =========================================================
add_heading_para("5. Components of a Behavioral Assessment Battery", level=2)

add_body(
    "Based on the reviewed evidence, a behavioral assessment battery for interhemispheric "
    "connection in school-aged children should integrate the following domains. In the "
    "motor-bimanual domain, finger tapping tasks (in-phase and anti-phase) quantified as "
    "relative phase and standard deviation of relative phase, reciprocal bimanual coordination "
    "tasks scored for timing asymmetry and failure rate, and unimanual and bimanual pegboard "
    "tasks (Purdue Pegboard, Grooved Pegboard) are well supported. In the reaction time domain, "
    "the Poffenberger CUD paradigm provides an estimate of IHTT, though researchers should note "
    "its limited reliability below age 8. In the auditory-linguistic laterality domain, "
    "consonant-vowel dichotic listening and the Dichotic Digits Test (DDT) quantify the "
    "right-ear advantage as an index of posterior callosal function. Supplementary contextual "
    "measures including the Edinburgh Handedness Inventory, age, sex, academic performance, "
    "and developmental history should accompany all assessments."
)

# =========================================================
# SECTION 6 — GAPS AND FUTURE DIRECTIONS
# =========================================================
add_heading_para("6. Gaps and Future Directions", level=2)

add_body(
    "Several important gaps remain in the behavioral assessment literature. First, purely "
    "behavioral IHTT measures lack sufficient reliability in children aged 6-8 years "
    "(Meissner et al., 2017), suggesting that hybrid paradigms combining behavioral tasks "
    "with event-related potentials or TMS-evoked potentials are necessary in younger "
    "school-aged children. Second, the directional asymmetry of transcallosal conduction "
    "documented by Bortoletto et al. (2021) remains unexplored in pediatric behavioral "
    "research; protocols that separately evaluate each direction of interhemispheric "
    "information flow are warranted. Third, large-scale normative datasets for behavioral "
    "IHTT and bimanual coordination metrics across the full school-age range, stratified "
    "by age, sex, and handedness, are currently limited. Finally, the ecological validity "
    "of laboratory-based bimanual tasks in relation to everyday functional activities "
    "such as writing, musical performance, and self-care in school settings requires "
    "further investigation."
)

# =========================================================
# SECTION 7 — CONCLUSION
# =========================================================
add_heading_para("7. Conclusion", level=2)

add_body(
    "The behavioral assessment of interhemispheric connections in school-aged children rests "
    "on a well-established neuroanatomical and functional framework, with the corpus callosum "
    "as the central mediating structure. The seminal work of Gooijers and Swinnen (2014) "
    "provides the conceptual architecture mapping distinct bimanual task demands onto "
    "regionally specific callosal subregions that guides the selection and interpretation "
    "of behavioral measures. The school years represent a period of intensive callosal "
    "maturation during which behavioral assessments of bimanual coordination, interhemispheric "
    "transfer time, and dichotic listening are sensitive to age-related changes and clinically "
    "meaningful variations associated with pathology, handedness, sex, and training. A "
    "comprehensive behavioral battery combining motor timing tasks, reaction time paradigms, "
    "and auditory laterality tests, supplemented by handedness questionnaires and age-stratified "
    "normative comparisons, provides a feasible, valid, and informative approach to "
    "characterizing interhemispheric connection in school-aged populations."
)

# =========================================================
# REFERENCES
# =========================================================
add_heading_para("References", level=2)

refs = [
    "Azatyan, T. (2023). The study of spatial representations of children with different degrees "
    "of interhemispheric interaction. Georgian Medical News, (345). "
    "https://pubmed.ncbi.nlm.nih.gov/38325311",

    "Bortoletto, M., Bonzano, L., Zazio, A., Ferrari, C., Pedulla, L., & Gasparotti, R. (2021). "
    "Asymmetric transcallosal conduction delay leads to finer bimanual coordination. Brain "
    "Stimulation, 14(2), 380-389. https://doi.org/10.1016/j.brs.2021.02.002",

    "Bradley, K. A., Juranek, J. J., Hannay, H. J., Cirino, P. T., Kramer, L. A., & Fletcher, "
    "J. M. (2024). Corpus callosum structure and auditory interhemispheric transfer in spina "
    "bifida myelomeningocele. Neuropsychology. https://doi.org/10.1037/neu0000915",

    "Chaddock-Heyman, L., Erickson, K. I., Kienzler, C., et al. (2018). Physical activity "
    "increases white matter microstructure in children. Frontiers in Neuroscience, 12, 950. "
    "https://doi.org/10.3389/fnins.2018.00950",

    "Dennis, E. L., Ellis, M. U., Marion, S. D., Jin, Y., Moran, L., & Olsen, A. (2015). "
    "Callosal function in pediatric traumatic brain injury linked to disrupted white matter "
    "integrity. Journal of Neuroscience, 35(28), 10202-10211. "
    "https://doi.org/10.1523/JNEUROSCI.1595-15.2015",

    "Gooijers, J., & Swinnen, S. P. (2014). Interactions between brain structure and behaviour: "
    "The corpus callosum and bimanual coordination. Neuroscience and Biobehavioral Reviews, "
    "43, 1-19. https://doi.org/10.1016/j.neubiorev.2014.03.008",

    "Hung, Y.-C., Robert, M. T., Friel, K. M., & Gordon, A. M. (2019). Relationship between "
    "integrity of the corpus callosum and bimanual coordination in children with unilateral "
    "spastic cerebral palsy. Frontiers in Human Neuroscience, 13, 334. "
    "https://doi.org/10.3389/fnhum.2019.00334",

    "Meissner, T. W., Friedrich, P., Ocklenburg, S., Genc, E., & Weigelt, S. (2017). Tracking "
    "the functional development of the corpus callosum in children using behavioral and evoked "
    "potential interhemispheric transfer times. Developmental Neuropsychology, 42(3), 182-196. "
    "https://doi.org/10.1080/87565641.2017.1315582",

    "Stipdonk, L. W., Boon, R. M., Franken, M. J. P., et al. (2022). Language lateralization in "
    "very preterm children: associating dichotic listening to interhemispheric connectivity and "
    "language performance. Pediatric Research, 91(6), 1524-1531. "
    "https://doi.org/10.1038/s41390-021-01691-6",

    "Weinstein, M., Green, D., Geva, R., et al. (2014). Interhemispheric and intrahemispheric "
    "connectivity and manual skills in children with unilateral cerebral palsy. Brain Structure "
    "and Function, 219(3), 1025-1040. https://doi.org/10.1007/s00429-013-0551-5",

    "Weinstein, M., Myers, V., Green, D., et al. (2015). Brain plasticity following intensive "
    "bimanual therapy in children with hemiparesis: Preliminary evidence. Neural Plasticity, "
    "2015, 891390. https://doi.org/10.1155/2015/891390",
]

for r in refs:
    add_ref(r)

# Save
out_path = "/tmp/workspace/literature-review/Interhemispheric_LitReview.docx"
doc.save(out_path)
print(f"Saved: {out_path}")

from docx import Document
from docx.shared import Pt, Inches
from docx.enum.text import WD_ALIGN_PARAGRAPH

doc = Document()

# Page margins
for section in doc.sections:
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    section.bottom_margin = Inches(1.0)
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# ---- TITLE ----
add_para(
    "Behavioral Assessment of Interhemispheric Connection in School-Aged Children: A Literature Review",
    bold=True, center=True, indent=False
)

# blank line
add_para("", indent=False)

# ---- HEADING ----
add_para("Literature Review", bold=True, center=False, indent=False)

# ---- 15 body lines ----
lines = [
    "The corpus callosum (CC) is the principal white matter commissure connecting the cerebral "
    "hemispheres and serves as the primary structural substrate for interhemispheric communication "
    "(Gooijers & Swinnen, 2014).",

    "Gooijers and Swinnen (2014) established in their seminal review that the CC actively mediates "
    "functional coupling between hemispheres, with its microstructural properties predicting "
    "behavioral performance on bimanual and cross-modal coordination tasks.",

    "The CC is topographically organized: the genu transmits prefrontal fibers, the body transmits "
    "premotor and motor fibers, and the splenium transmits parietal, temporal, and occipital fibers, "
    "a regional arrangement that determines which behavioral domains are selectively affected by "
    "callosal disruption (Witelson, 1989, as cited in Gooijers & Swinnen, 2014).",

    "School-aged children (6-12 years) represent a critical window of callosal myelination and "
    "axonal pruning during which interhemispheric communication undergoes rapid measurable "
    "refinement, reflected in progressive increases in fractional anisotropy and decreases in "
    "mean diffusivity on diffusion tensor imaging (Chaddock-Heyman et al., 2018).",

    "The most widely used behavioral measure of CC function is interhemispheric transfer time "
    "(IHTT), estimated as the crossed-uncrossed difference (CUD) in simple reaction time using "
    "the Poffenberger paradigm (Gooijers & Swinnen, 2014).",

    "Meissner et al. (2017) demonstrated that electrophysiological CUDs were significantly faster "
    "in adults than in 7-year-olds, confirming ongoing callosal development at this age, while "
    "behavioral CUDs proved unreliable at 6-month retest, indicating that purely behavioral IHTT "
    "may underestimate callosal immaturity in younger school-aged children.",

    "Gooijers and Swinnen (2014) identified two complementary callosal roles in bimanual "
    "coordination: an inhibitory-decoupling function permitting independent asymmetric hand "
    "movements, and a coordinative-coupling function synchronizing the timing of symmetric "
    "bimanual movements.",

    "Hung et al. (2019) examined 39 children with unilateral spastic cerebral palsy using DTI and "
    "a kinematic bimanual drawer-opening task and found that splenium integrity specifically "
    "predicted temporal coordination, confirming regional callosal specificity in school-aged "
    "pediatric populations.",

    "Azatyan (2023) assessed interhemispheric interaction in 73 school-aged children (8-11 years) "
    "using bimanual motor tests and found reciprocal coordination disorders in 41% of participants, "
    "predominantly as left-hand failures, with deficits correlating significantly with spatial "
    "representation performance.",

    "Dichotic listening (DL) provides a behavioral index of posterior callosal integrity through "
    "the right-ear advantage (REA), which reflects left-hemispheric speech dominance and "
    "interhemispheric relay via the splenium (Gooijers & Swinnen, 2014).",

    "Bradley et al. (2024) demonstrated that absence of the normative REA in children with spina "
    "bifida myelomeningocele was associated with splenium hypogenesis, confirming the dependence "
    "of behavioral dichotic laterality on posterior callosal integrity.",

    "Stipdonk et al. (2022) further showed that DL lateralization in very preterm children "
    "correlated with interhemispheric structural connectivity and language performance, "
    "strengthening the clinical validity of DL as a behavioral callosal measure.",

    "Dennis et al. (2015) reported in pediatric traumatic brain injury that impaired behavioral "
    "and electrophysiological IHTT co-occurred with lower CC fractional anisotropy and poorer "
    "neurocognitive outcomes, validating behavioral IHTT as a clinically meaningful endpoint "
    "in acquired childhood brain injury.",

    "Bortoletto et al. (2021) demonstrated in adults that asymmetric transcallosal conduction "
    "delay - differing latencies for right-to-left versus left-to-right hemisphere transfer - "
    "was the strongest predictor of bimanual coordination quality, a directionality consideration "
    "that future pediatric behavioral protocols should address.",

    "A comprehensive behavioral battery for assessing interhemispheric connection in school-aged "
    "children should include in-phase and anti-phase finger tapping tasks, reciprocal bimanual "
    "coordination tests, Poffenberger CUD reaction time, dichotic listening, and the Edinburgh "
    "Handedness Inventory, with age-stratified normative comparisons across yearly intervals "
    "(Gooijers & Swinnen, 2014; Meissner et al., 2017; Azatyan, 2023).",
]

for line in lines:
    add_para(line)

# blank line before references
add_para("", indent=False)

# ---- REFERENCES HEADING ----
add_para("References", bold=True, center=False, indent=False)

refs = [
    "Azatyan, T. (2023). The study of spatial representations of children with different degrees of interhemispheric interaction. Georgian Medical News. https://pubmed.ncbi.nlm.nih.gov/38325311",
    "Bortoletto, M., Bonzano, L., Zazio, A., Ferrari, C., Pedulla, L., & Gasparotti, R. (2021). Asymmetric transcallosal conduction delay leads to finer bimanual coordination. Brain Stimulation, 14(2), 380-389.",
    "Bradley, K. A., Juranek, J. J., Hannay, H. J., Cirino, P. T., Kramer, L. A., & Fletcher, J. M. (2024). Corpus callosum structure and auditory interhemispheric transfer in spina bifida myelomeningocele. Neuropsychology. https://doi.org/10.1037/neu0000915",
    "Chaddock-Heyman, L., Erickson, K. I., Kienzler, C., et al. (2018). Physical activity increases white matter microstructure in children. Frontiers in Neuroscience, 12, 950.",
    "Dennis, E. L., Ellis, M. U., Marion, S. D., Jin, Y., Moran, L., & Olsen, A. (2015). Callosal function in pediatric traumatic brain injury linked to disrupted white matter integrity. Journal of Neuroscience, 35(28), 10202-10211.",
    "Gooijers, J., & Swinnen, S. P. (2014). Interactions between brain structure and behaviour: The corpus callosum and bimanual coordination. Neuroscience and Biobehavioral Reviews, 43, 1-19.",
    "Hung, Y.-C., Robert, M. T., Friel, K. M., & Gordon, A. M. (2019). Relationship between integrity of the corpus callosum and bimanual coordination in children with unilateral spastic cerebral palsy. Frontiers in Human Neuroscience, 13, 334.",
    "Meissner, T. W., Friedrich, P., Ocklenburg, S., Genc, E., & Weigelt, S. (2017). Tracking the functional development of the corpus callosum in children using behavioral and evoked potential interhemispheric transfer times. Developmental Neuropsychology, 42(3), 182-196.",
    "Stipdonk, L. W., Boon, R. M., Franken, M. J. P., et al. (2022). Language lateralization in very preterm children: Associating dichotic listening to interhemispheric connectivity and language performance. Pediatric Research, 91(6), 1524-1531.",
]

for r in refs:
    add_ref(r)

out = "/tmp/workspace/literature-review/Interhemispheric_LitReview_Short.docx"
doc.save(out)
print(f"Saved: {out}")