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Featured researches published by Peter J. Marshall.


Science | 2007

Cognitive Recovery in Socially Deprived Young Children: The Bucharest Early Intervention Project

Charles A. Nelson; Charles H. Zeanah; Nathan A. Fox; Peter J. Marshall; Anna T. Smyke; Donald Guthrie

In a randomized controlled trial, we compared abandoned children reared in institutions to abandoned children placed in institutions but then moved to foster care. Young children living in institutions were randomly assigned to continued institutional care or to placement in foster care, and their cognitive development was tracked through 54 months of age. The cognitive outcome of children who remained in the institution was markedly below that of never-institutionalized children and children taken out of the institution and placed into foster care. The improved cognitive outcomes we observed at 42 and 54 months were most marked for the youngest children placed in foster care. These results point to the negative sequelae of early institutionalization, suggest a possible sensitive period in cognitive development, and underscore the advantages of family placements for young abandoned children.


Clinical Neurophysiology | 2002

Development of the EEG from 5 months to 4 years of age.

Peter J. Marshall; Yair Bar-Haim; Nathan A. Fox

OBJECTIVES This report provides a systematic longitudinal analysis of the EEG from infancy into early childhood. Particular emphasis is placed on the empirical confirmation of a 6-9 Hz alpha-range frequency band that has previously been used in the infant EEG literature. METHODS EEG data in 1-Hz bins from 3 to 12 Hz were analyzed from a longitudinal sample of 29 participants at 5, 10, 14, 24, and 51 months of age. RESULTS Inspection of power spectra averaged across the whole sample indicated the emergence of a peak in the 6-9 Hz range across multiple scalp regions. Coding of peaks in the power spectra of individual infants showed a clear developmental increase in the frequency of this peak. A rhythm in the 6-9 Hz emerged at central sites that was independent of the classical alpha rhythm at posterior sites. The relative amplitude of this central rhythm peaked in the second year of life, when major changes are occurring in locomotor behavior. CONCLUSIONS The 6-9 Hz band is a useful alpha-range band from the end of the first year of life into early childhood. The findings also complement other research relating the infant central rhythm with the adult sensorimotor mu rhythm.


American Journal of Psychiatry | 2009

Institutional Rearing and Psychiatric Disorders in Romanian Preschool Children

Charles H. Zeanah; Helen L. Egger; Anna T. Smyke; Charles A. Nelson; Nathan A. Fox; Peter J. Marshall; Donald Guthrie

OBJECTIVE There is increasing interest in the relations between adverse early experiences and subsequent psychiatric disorders. Institutional rearing is considered an adverse caregiving environment, but few studies have systematically examined its effects. This study aimed to determine whether removing young children from institutional care and placing them with foster families would reduce psychiatric morbidity at 54 months of age. METHOD Young children living in institutions in Bucharest were enrolled when they were between 6 and 30 months of age. Following baseline assessment, 136 children were randomly assigned to care as usual (continued institutional care) or to removal and placement in foster care that was created as part of the study. Psychiatric disorders, symptoms, and comorbidity were examined by structured psychiatric interviews of caregivers of 52 children receiving care as usual and 59 children in foster care when the children were 54 months of age. Both groups were compared to 59 typically developing, never-institutionalized Romanian children recruited from pediatric clinics in Bucharest. Foster care was created and supported by social workers in Bucharest who received regular consultation from U.S. clinicians. RESULTS Children with any history of institutional rearing had more psychiatric disorders than children without such a history (53.2% versus 22.0%). Children removed from institutions and placed in foster families were less likely to have internalizing disorders than children who continued with care as usual (22.0% versus 44.2%). Boys were more symptomatic than girls regardless of their caregiving environment and, unlike girls, had no reduction in total psychiatric symptoms following foster placement. CONCLUSIONS Institutional rearing was associated with substantial psychiatric morbidity. Removing young children from institutions and placing them in families significantly reduced internalizing disorders, although girls were significantly more responsive to this intervention than boys.


Journal of Cognitive Neuroscience | 2004

A Comparison of the Electroencephalogram between Institutionalized and Community Children in Romania

Peter J. Marshall; Nathan A. Fox

Electroencephalographic (EEG) data were collected from a sample of institutionalized infants and young children in Bucharest, Romania, and were compared with EEG data from age-matched children from the local community who had never been institutionalized and who were living with their families in the Bucharest area. Compared with the never-institutionalized group, the institutionalized group showed a pattern of increased low-frequency (theta) power in posterior scalp regions and decreased high-frequency (alpha and beta) power, particularly at frontal and temporal electrode sites. This finding is consistent with EEG studies of children facing environmental adversity and children with learning disorders. The institutionalized group also showed less marked hemispheric EEG asymmetries than the never-institutionalized group, particularly in the temporal region. The results are discussed in the context of two models: that the pattern of EEG in the institutionalized children reflects a maturational lag in nervous system development, or that it reflects tonic cortical hypoactivation.


Developmental Psychobiology | 2000

Developmental changes in heart period and high-frequency heart period variability from 4 months to 4 years of age.

Yair Bar-Haim; Peter J. Marshall; Nathan A. Fox

Cardiac measures of heart period and high-frequency heart period variability are increasingly employed as dependent variables in studies of social and emotional development in infancy and childhood. This study describes significant developmental increases in these measures in a longitudinal sample assessed at 4, 9, 14, 24, and 48 months of age. In addition, developmental changes in the characteristics of the heart period power spectra are described. These changes have implications for the quantification of high-frequency heart period variability in infancy and childhood. First, shorter analysis epoch lengths may be used for younger infants. Second, the commonly used high-frequency band for infants (0.24-1.04 Hz) appears to reach its practical limit at an age of around four years. Findings are discussed in relation to the design of developmental psychophysiological studies.


Developmental Psychology | 2008

Behavioral Reactivity and Approach-Withdrawal Bias in Infancy.

Amie Ashley Hane; Nathan A. Fox; Heather A. Henderson; Peter J. Marshall

Seven hundred seventy-nine infants were screened at 4 months of age for motor and emotional reactivity. At age 9 months, infants who showed extreme patterns of motor and negative (n = 75) or motor and positive (n = 73) reactivity and an unselected control group (n = 86) were administered the Laboratory Temperament Assessment Battery, and baseline electroencephalogram data were collected. Negatively reactive infants showed significantly more avoidance than positively reactive infants and displayed a pattern of right frontal electroencephalogram asymmetry. Positively reactive infants exhibited significantly more approach behavior than controls and exhibited a pattern of left frontal asymmetry. Results support the notion that approach-withdrawal bias underlies reactivity in infancy.


Developmental Science | 2011

Neural correlates of action observation and execution in 14-month-old infants: an event-related EEG desynchronization study

Peter J. Marshall; Thomas Young; Andrew N. Meltzoff

There is increasing interest in neurobiological methods for investigating the shared representation of action perception and production in early development. We explored the extent and regional specificity of EEG desynchronization in the infant alpha frequency range (6-9 Hz) during action observation and execution in 14-month-old infants. Desynchronization during execution was restricted to central electrode sites, while action observation was associated with a broader desynchronization across frontal, central, and parietal regions. The finding of regional specificity in the overlap between EEG responses to action execution and observation suggests that the rhythm seen in the 6-9 Hz range over central sites in infancy shares certain properties with the adult mu rhythm. The magnitude of EEG desynchronization to action perception and production appears to be smaller for infants than for adults and older children, suggesting developmental change in this measure.


Development and Psychopathology | 2008

Effects of early intervention on EEG power and coherence in previously institutionalized children in Romania.

Peter J. Marshall; Bethany C. Reeb; Nathan A. Fox; Charles A. Nelson; Charles H. Zeanah

Two groups of Romanian children were compared on spectral power and coherence in the electroencephalogram (EEG) in early childhood. One group consisted of previously institutionalized children who had been randomly assigned to a foster care intervention at a mean age of 23 months. The second group had been randomized to remain in institutional care. Because of a policy of noninterference, a number of these children also experienced placement into alternative family care environments. There were minimal group differences between the foster care and institutionalized groups in EEG power and coherence across all measured frequency bands at 42 months of age. However, age at foster care placement within the foster care group was correlated with certain measures of EEG power and coherence. Earlier age at foster care placement was associated with increased alpha power and decreased short-distance EEG coherence. Further analyses separating age at placement from duration of intervention suggest that this effect may be more robust for EEG coherence than EEG band power. Supplementary analyses examined whether the EEG measures mediated changes in intellectual abilities within the foster care children, but no clear evidence of mediation was observed.


Biological Psychiatry | 2010

Delayed Maturation in Brain Electrical Activity Partially Explains the Association Between Early Environmental Deprivation and Symptoms of Attention-Deficit/Hyperactivity Disorder

Katie A. McLaughlin; Nathan A. Fox; Charles H. Zeanah; Margaret A. Sheridan; Peter J. Marshall; Charles A. Nelson

BACKGROUND Children raised in institutional settings are exposed to social and environmental circumstances that may deprive them of expected environmental inputs during sensitive periods of brain development that are necessary to foster healthy development. This deprivation is thought to underlie the abnormalities in neurodevelopment that have been found in previously institutionalized children. It is unknown whether deviations in neurodevelopment explain the high rates of developmental problems evident in previously institutionalized children, including psychiatric disorders. METHODS We present data from a sample of children raised in institutions in Bucharest, Romania (n = 117) and an age- and sex-matched sample of community control subjects (n = 49). Electroencephalogram data were acquired following entry into the study at age 6 to 30 months, and a structured diagnostic interview of psychiatric disorders was completed at age 54 months. RESULTS Children reared in institutions evidenced greater symptoms of attention-deficit/hyperactivity disorder, anxiety, depression, and disruptive behavior disorders than community controls. Electroencephalogram revealed significant reductions in alpha relative power and increases in theta relative power among children reared in institutions in frontal, temporal, and occipital regions, suggesting a delay in cortical maturation. This pattern of brain activity predicted symptoms of hyperactivity and impulsivity at age 54 months, and significantly mediated the association between institutionalization and attention-deficit/hyperactivity disorder symptoms. Electroencephalogram power was unrelated to depression, anxiety, or disruptive behaviors. CONCLUSIONS These findings document a potential neurodevelopmental mechanism underlying the association between institutionalization and psychiatric morbidity. Deprivation in social and environmental conditions may perturb early patterns of neurodevelopment and manifest as psychiatric problems later in life.


PLOS ONE | 2010

Timing of Intervention Affects Brain Electrical Activity in Children Exposed to Severe Psychosocial Neglect

Ross E. Vanderwert; Peter J. Marshall; Charles A. Nelson; Charles H. Zeanah; Nathan A. Fox

Background Early psychosocial deprivation has profound effects on brain activity in the young child. Previous reports have shown increased power in slow frequencies of the electroencephalogram (EEG), primarily in the theta band, and decreased power in higher alpha and beta band frequencies in infants and children who have experienced institutional care. Methodology/Principal Findings We assessed the consequences of removing infants from institutions and placing them into a foster care intervention on brain electrical activity when children were 8 years of age. We found the intervention was successful for increasing high frequency EEG alpha power, with effects being most pronounced for children placed into foster care before 24 months of age. Conclusions/Significance The dependence on age of placement for the effects observed on high frequency EEG alpha power suggests a sensitive period after which brain activity in the face of severe psychosocial deprivation is less amenable to recovery.

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Lorna C. Quandt

University of Pennsylvania

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