Emese Nagy

Sex-related ERP differences in deviance detection

The effect of sex on neural mechanisms of auditory mismatch detection was examined using dense sensor array (128 channel) event-related potential recordings (ERPs). ERPs of 32 right-handed subjects (16 males) were recorded to frequent (85%, 880 Hz) and infrequent (15%, 1480 Hz) tones. There were no sex differences in mismatch negativity (80-180 ms), however, the fronto-central P2 (180-260 ms) was less positive in males (F=12.56, P<0.005) and the N2 (260-340 ms) was more negative in males (F=6.28, P<0.05). The increased negativity in males spanning the P2 and N2 may index a top-down process of attention bias towards novelty. This result supports the hypothesis of an adaptive, sexually dimorphic processing of novel events in humans.

Index Finger Movement Imitation by Human Neonates: Motivation, Learning, and Left-Hand Preference

Imitation of a fine motor movement, index finger protrusion, was examined in 39 neonates using an ethologically based objective coding system. Results confirmed that imitation of finger movements exists, and infants demonstrated “learning” as imitation developed through an incomplete imitation stage. Neonatal imitation was more frequently left-handed, an early sign of laterality in motivation to be investigated further. The existence of index finger imitation in human neonates indicates that volitional control of individuated finger movements develops much earlier than previously thought. The differential increase of index finger protrusion movements during the imitation periods suggests that this behavior is not an automatic response triggered by general arousal but instead is a true indicator of purposeful neonatal imitation.

Innate Intersubjectivity: Newborns' Sensitivity to Communication Disturbance.

In most of our social life we communicate and relate to others. Successful interpersonal relating is crucial to physical and mental well-being and growth. This study, using the still-face paradigm, demonstrates that even human neonates (n = 90, 3-96 hr after birth) adjust their behavior according to the social responsiveness of their interaction partner. If the interaction partner becomes unresponsive, newborns will also change their behavior, decrease eye contact, and display signs of distress. Even after the interaction partner resumes responsiveness, the effects of the communication disturbance persist as a spillover. These results indicate that even newborn infants sensitively monitor the behavior of others and react as if they had innate expectations regarding rules of interpersonal interaction.

Gender-Related Heart Rate Differences in Human Neonates

The aim of the present study was to examine gender-related differences in heart rate of human neonates controlled for their behavior. Previous studies could not find any difference in male and female fetuses and newborns, although this gender-dependent difference clearly exists in children and adults. The heart rate of 99 newborns (47 girls and 52 boys) was measured with simultaneous video recording of their behavior. Results proved that alert newborns showed the same difference as adults: boys had a significantly lower baseline heart rate than girls. This suggests that heart rate is gender-dependent from birth onward.

Breastfeeding duration and previous breastfeeding experience

The aim of this study was to examine the effect of duration of earlier breastfeeding on the duration of breastfeeding with subsequent births. Medical records of 327 women who had had at least two deliveries were analysed; 89 of these women had had three deliveries. The average duration of breastfeeding increased from 6.01 mo to 6.85 mo with the second baby, but did not increase significantly with the third. A significant negative correlation was found between duration of first breastfeeding and change of breastfeeding duration at the second breastfeeding. Mothers who breastfed their first child for 0–7 mo significantly increased the duration of breastfeeding with the second child, whereas mothers who breastfed their firstborn for 8 mo or longer significantly reduced breastfeeding with the second baby.

Prevalence rates and socioeconomic characteristics of post-partum depression in Hungary

The rapid socioeconomic transition in post-communist Hungary adversely affected the overall morbidity and mortality rates in the 1990s. Prevalence data on depressive disorders from the region are still scarce, however. This study reports the findings of the first epidemiological survey, using the Edinburgh Postnatal Depression Scale (EPDS) and the Beck Depression Inventory (BDI), on the prevalence of post-partum depression and the associated risk factors in Hungary. A total of 1030 mothers who delivered their babies between May and July 1999 in 16 counties in Hungary were screened for depressive symptoms 3-26 weeks post-partum. The survey found that 10.81% of the sample was above the cut-off score of 13, and the EPDS detected post-partum depressive symptoms with 76% (95% confidence interval (CI)=60.5-87.1) sensitivity and 92% (95% CI=90.5-94.1) specificity. In addition, 24 socio-demographic, socio-psychiatric data and personal and obstetric variables were surveyed. Results of a hierarchical logistic regression analysis showed that depression of the mother during pregnancy was the strongest predictor of depressive symptoms post-partum. Depression before pregnancy, housing conditions, marital relationship status and family history of alcohol problems were also identified as predictors for post-partum depressive symptoms.

Fetal Behavioural Responses to Maternal Voice and Touch

Background Although there is data on the spontaneous behavioural repertoire of the fetus, studies on their behavioural responses to external stimulation are scarce. Aim, Methods The aim of the current study was to measure fetal behavioural responses in reaction to maternal voice; to maternal touch of the abdomen compared to a control condition, utilizing 3D real-time (4D) sonography. Behavioural responses of 23 fetuses (21st to 33rd week of gestation; N = 10 in the 2nd and N = 13 in the 3rd trimester) were frame-by-frame coded and analyzed in the three conditions. Results Results showed that fetuses displayed more arm, head, and mouth movements when the mother touched her abdomen and decreased their arm and head movements to maternal voice. Fetuses in the 3rd trimester showed increased regulatory (yawning), resting (arms crossed) and self-touch (hands touching the body) responses to the stimuli when compared to fetuses in the 2nd trimester. Conclusion In summary, the results from this study suggest that fetuses selectively respond to external stimulation earlier than previously reported, fetuses actively regulated their behaviours as a response to the external stimulation, and that fetal maturation affected the emergence of these differential responses to the environment.

The neural mechanisms of reciprocal communication

Imitation in humans has been attributed to increased activation of the mirror neuron system, but there is no neural model to explain reciprocal communication. In this study, we investigated whether reciprocal, communicative, imitative exchanges activate the same neural system as imitation of simple movements, and whether the neural network subserving communication is lateralized. Fifteen participants were tested using functional magnetic resonance imaging with an online interactive-imitative paradigm while they performed finger movements for three different purposes: (1) to imitate the experimenter, (2) to elicit an imitation from the experimenter, and (3) to simply perform the movement. Subtraction analysis (imitation > movement, initiation > movement) revealed the activation of a strongly lateralized network, where the infra-parietal lobule (IPL) activation was lateralized to the left, while the infero-frontal gyrus (IFG) activation was to the right. It is concluded that imitation in a communicative paradigm recruits a lateralized network, with left fronto- and right parietal activation, that overlaps with a network that subserves understanding of an Others intentions in relation to the Self. This finding lends plausibility to the suggestion that the neural network for imitation evolved to support interpersonal communication.

Learning to imitate individual finger movements by the human neonate.

Imitation in human neonates, unlike imitation in young infants, is still regarded as controversial. Four studies with 203 newborns are presented to examine the imitation of index finger, two- and three-finger movements in human neonates. Results found differential imitations of all three modelled gestures, a left-handed pattern, and a rapid learning mechanism. The lateralized behavioural pattern suggests the involvement of a right lateralized neural network, and the mechanisms described in this study - (i) the accurate imitation of all aspects of the models movements, (ii) the rapid learning component, and the (iii) the early sensitive period might fulfil the criteria for filial imprinting.

From symmetry to asymmetry? The development of smile.

The left side of the face has been reported to be more expressive than the right side in human adults. The developmental origin of this lateralization, however, is unknown. Chimeric still composite photos of smiling faces of 0-5 months (n=61), 6-12 months (n=67) old infants, 3-8 years old children (n=78), and 32 adults (>18 years) were rated for intensity by 90 judges. The results showed left-hemiface dominance in adults only, and not in infants or children. It can be speculated that this early functional symmetry may evolutionarily increase attractiveness and elicits secure bonding and care.