Judith M. Gardner

Prenatal cocaine exposure effects on arousal-modulated attention during the neonatal period

The organization of arousal and attention as a function of intrauterine cocaine exposure was investigated in 180 normal nursery infants prior to hospital discharge and at 1 month of age. This was done by studying visual looking preferences when infants were in three arousal conditions: less aroused (after feeding); more aroused-endogenous (before feeding); and more aroused-exogenous (after feeding but including 8-Hz visual stimulation prior to each visual preference trial). The stimuli were light panels illuminated at three temporal frequencies between 1 and 8 Hz presented in pairs using a balanced presentation series of trials. Infants not exposed to cocaine demonstrated strong arousal-modulated attention, preferring faster frequencies when less aroused and slower frequencies when more aroused in both endogenous and exogenous conditions. In contrast, cocaine-exposed infants showed a lack of arousal-modulated attention and preferred faster frequencies of stimulation regardless of arousal condition. Similar differences in arousal-modulated attention as a function of cocaine exposure were obtained at 1 month after birth, indicating that these effects lasted longer than would be reasonable to attribute to the active presence of cocaine or its metabolites. This form of stimulus-seeking behavior was shown to be independent of confounding factors associated with prenatal cocaine exposure such as the absence of prenatal care, alcohol use, minority status, or gender, as well as mediating factors associated with growth such as birthweight. A direct and more chronic effect of intrauterine cocaine exposure on arousal-modulated attention and presumably on the developing CNS therefore was supported.

Early Medical and Behavioral Characteristics of NICU Infants Later Classified With ASD

OBJECTIVES: Recent evidence suggests higher prevalence of autism spectrum disorder (ASD) in NICU graduates. This aim of this study was to identify retrospectively early behaviors found more frequently in NICU infants who went on to develop ASD. METHODS: Twenty-eight NICU graduates who later received a diagnosis of ASD were compared with 2169 other NICU graduates recruited from 1994 to 2005. They differed in gender, gestational age, and birth cohort. These characteristics were used to draw a matched control sample (n = 112) to determine which, if any, early behaviors discriminated subsequent ASD diagnosis. Behavioral testing at targeted ages (adjusted for gestation) included the Rapid Neonatal Neurobehavioral Assessment (hospital discharge, 1 month), Arousal-Modulated Attention (hospital discharge, 1 and 4 months), and Bayley Scales of Infant Development (multiple times, 4–25 months). RESULTS: At 1 month, children with ASD but not control children had persistent neurobehavioral abnormalities and higher incidences of asymmetric visual tracking and arm tone deficits. At 4 months, children with ASD had continued visual preference for higher amounts of stimulation than did control children, behaving more like newborns. Unlike control children, children with ASD had declining mental and motor performance by 7 to 10 months, resembling infants with severe central nervous system involvement. CONCLUSIONS: Differences in specific behavior domains between NICU graduates who later receive a diagnosis of ASD and matched NICU control children may be identified in early infancy. Studies with this cohort may provide insights to help understand and detect early disabilities, including ASD.

Development of arousal-modulated visual preferences in early infancy

Looking preferences to visual temporal frequencies between 1 and 8 Hz were studied longitudinally at 3 ages (newborn, 1 month, 4 months; N = 77) in 3 conditions: less aroused (after feeding), more aroused-internal (before feeding), and more aroused-external (after feeding with 8 Hz visual stimulation before each trial). Replicating and extending previous results, a strong interaction between arousal level and stimulus frequency was found at newborn and 1 month. Infants preferred faster stimuli when less aroused and slower stimuli when more aroused, with no differences between the 2 more aroused conditions even though produced by different operations. At 4 months, the interaction with arousal no longer existed; faster stimuli were preferred in all conditions. Thus, after the transition in visual behavior normally occurring at 2-3 months, arousal no longer played a major role, possibly as a result of emergent cortical sensory-specific attention. Differentiation within and between the processes influencing levels of arousal and attention appears to occur during early infancy. To investigate transitions in these processes, the present study extends previous findings of arousal-modulated attention in newborn infants to infants at 1 and 4 months of age. For neonates, arousal and attention work interdependently as a single, quantitatively organized self-limiting homeostatic system that combines the effects of internal and external factors to specify systematic directional shifts in attention to particular stimuli (see Gardner & Karmel, 1983; Karmel, Gardner, & Magnano, 1991; Turkewitz, Gardner, & Lewkowicz, 1984; Turkewitz, Lewkowicz, & Gardner, 1983). This basic characterization of arousal-modulated attention is evidenced by similar systematic shifts in visual preferences toward less stimulating events (e.g., slower temporal frequencies or less contour in spatial patterns) when neonates are both endogenously more aroused (unswaddled before

Determinants of Infant Perception

Publisher Summary This chapter describes that the young infants are responsive to quantitative aspects of the world. It presents evidence that, for young infants, it is only the overall amount of stimulation to which infants respond. The data presented indicate that stimulus attributes, such as size and luminance are additive, and a reduction in stimulation in one attribute is substitutable by an increment in another. Furthermore, stimulation from different modalities is additive and young infants ignore the differences between inputs in different modalities, and respond to these inputs as equivalent when their effective intensity is the same. The chapter uses a series of studies to examine the outcomes that are logically predicted from the view that infants respond to the world in terms of the amount rather than the kind of stimulation. It examines response measures, such as finger movements, visual preferences, and cardiac responses. These measures have been used in conjunction with variations along a number of quantitative dimensions, including size, distance, luminance, configuration, spatial and temporal frequency, and sound pressure level.

Arousal/Visual Preference Interactions in High-Risk Neonates

We investigated the organization of arousal and attention processes in 138 neurologically at-risk neonates by studying visual preferences when the infants were in 3 arousal conditions: less aroused (after feeding while swaddled), more aroused-internal (before feeding while unswaddled), and more aroused-external (after feeding while swaddled with 8-Hz visual stimulation before each trial). The stimuli were unpatterned light panels illuminated at temporal frequencies of 1,2,4, and 8 Hz. Four brain insult groups were defined by cranial ultrasonography and brainstem auditory evoked response tests. There were no differences in looking preferences in the 2 more aroused conditions. A previously reported interaction between arousal level and stimulus frequency was replicated, with infants preferring faster frequencies when arousal was decreased. Brain insult reduced this interaction by shifting preference functions when less aroused toward less stimulation. Infants cannot gain information, learn about the world, or interact socially unless they first actively attend to relevant features of their environment. Typically, term infants are born with most of their physiological systems coordinated and well adapted to the immediate environment they are likely to face. This structural and functional organization is evident in the fundamental processes of state modulation and attention to stimulation that are necessary antecedent conditions to learning and memory. For neonates, it appears that arousal and attention work interdependently as a quantitatively organized homeostatic system that combines the effects of internal and external factors to specify attention to particular stimuli. Thus, systematic directional shifts in attention occur when either external or internal factors vary. For example, when infants are more aroused (and have higher levels of internal activity), they orient toward less intense stimuli, and when infants are less aroused (and have lower levels of internal activity), they orient toward more intense stimuli (Gardner & Karmel, 1984; Gardner, Lewkowicz, Rose, & Karmel, 1986; Gardner & Turkewitz, 1982; Lawson & Turkewitz, 1980; Lewkowicz & Turkewitz, 1981).

Parent PDD behavior inventory profiles of young children classified according to autism diagnostic observation schedule-generic and autism diagnostic interview-revised criteria.

Quantitative variations in score profiles from the parent version of the PDD Behavior Inventory (PDDBI) were examined in young Autism and PDD-NOS groups defined by ADOS-G and ADI-R criteria, relative to a not spectrum (NS) group of similar age. Both the Autism and the PDD-NOS group profiles markedly differed from the NS group. The most sensitive measures of group differences were those domain and composite scores that assessed social communication competence, as well as the overall Autism Composite score. Sensitivity, specificity and positive and negative predictability measures were quite good for these measures. It was concluded that the PDDBI is useful in assisting in the differential diagnosis of autism spectrum disorder.

The transition to oral feeding in low-risk premature infants: relation to infant neurobehavioral functioning and mother-infant feeding interaction.

BACKGROUND The achievement of oral feeding is a critical task for the premature infant-mother dyad, yet neurobehavioral and relational factors associated with feeding difficulties of low-risk premature infants during hospitalization are not well understood. AIM To examine the relations between infant neurobehavioral functioning, the transition to oral feeding, and the emerging mother-infant feeding relationship in premature infants. STUDY DESIGN AND SUBJECTS Ninety-seven low-risk premature infants (birth weight>1000 g; gestational age>30 weeks) and their mothers were followed at the NICU. Neurobehavioral functioning was assessed with the Rapid Neonatal Neurobehavioral Assessment Procedure. OUTCOME MEASURES The duration of the transition to oral feeding and specific feeding difficulties during the transition were assessed. Infant feeding robustness, suck and milk transfer rates, and maternal adaptability, affect, intrusiveness and distractibility were coded from videotaped mother-infant feeding interactions prior to discharge from the NICU. RESULTS Thirty percent of the infants presented feeding difficulties during the transition to oral feedings. Infants with abnormal neurobehavioral functioning (37% of the cohort) showed more feeding difficulties, slower suck rates, and lower feeding robustness, and their mothers displayed less adaptive and more intrusive behavior. Maternal intrusiveness was related to lower feeding robustness and to lower suck and milk transfer rates. Neurobehavioral functioning and maternal feeding behavior predicted feeding robustness. CONCLUSIONS Less intact neurobehavioral functioning in the neonatal period is related to difficulties during the transition to oral feeding and to less optimal early mother-infant feeding interactions. Low-risk premature infants with poor neurobehavioral functioning should receive special attention and care.

Feeding-based arousal effects on visual recognition memory in early infancy.

Arousal effects on a 1-trial visual recognition paired-comparison task were studied at newborn, 1-month, and 4-month test ages. Infants were tested before and after feeding, with arousal assumed to be lower after feeding. Newborns and 1-month-olds shifted from a familiarity preference before feeding to a novelty preference after feeding. A control group tested only after feeding confirmed that this shift was not due to increased stimulus exposure from the prefeeding test. By 4 months, infants showed novelty preferences independent of feeding. This age by arousal interaction for recognition memory extends previous knowledge by including endogenous arousal with age, stimulus, and length of exposure as contributors to familiarity-novelty preferences. It also extends and provides converging evidence for arousal effects on visual attention in early infancy found previously with preferential looking. A shift from subcortical to cortical dominance is supported.

Neonatal Brainstem Function and 4‐Month Arousal‐Modulated Attention Are Jointly Associated With Autism

The authors evaluated the contribution of initially abnormal neonatal auditory brainstem responses (ABRs) and 4‐month arousal‐modulated attention visual preference to later autism spectrum disorder (ASD) behaviors in neonatal intensive care unit (NICU) graduates. A longitudinal study design was used to compare NICU graduates with normal ABRs (n = 28) to those with initially abnormal ABRs (n = 46) that later resolved. At 4 months postterm age, visual preference (measured after feeding) for a random check pattern flashing at 1, 3, or 8 Hz and gestational age (GA) served as additional predictors. Outcome measures were PDD Behavior Inventory (PDDBI) scores at 3.4 years (standard deviation = 1.2), and developmental quotients (DQ) obtained around the same age with the Griffiths Mental Development Scales (GMDS). Preferences for higher rates of stimulation at 4 months were highly correlated with PDDBI scores (all P‐values < 0.01) and the GMDS Hearing and Speech DQ, but only in those with initially abnormal ABRs. Effects were strongest for a PDDBI social competence measure most associated with a diagnosis of autism. For those with abnormal ABRs, increases in preference for higher rates of stimulation as infants were linked to nonlinear increases in severity of ASD at 3 years and to an ASD diagnosis. Abnormal ABRs were associated with later reports of repetitive and ritualistic behaviors irrespective of 4‐month preference for stimulation. The joint occurrence of initially abnormal neonatal ABRs and preference for more stimulation at 4 months, both indices of early brainstem dysfunction, may be a marker for the development of autism in this cohort. Autism Res 2012, ●●:●●–●●.

Neurobehavioral Indicators of Early Brain Insult in High-Risk Neonates.

Etude des performances neurocomportementales chez 248 nouveau-nes presentant des risques de problemes neurologiques.