Depressed mothers’ infants show less negative affect during non-contingent interactions

Infants of depressed and non-depressed mothers were videotaped interacting with their mothers in the [Nadel, J., Carchon, I., Kervella, C., Marcelli, D., & Reserbat-Plantey, D. (1999). Report: Expectancies for social contingency in 2-month-olds. Developmental Science, 2, 164–173] paradigm which consists of three segments including: (1) a free play, contingent interaction, (2) a non-contingent replay of the mothers’ behavior that had been videotaped during the first segment, and (3) a return to a free play, contingent interaction. As compared to infants of non-depressed mothers, infants of depressed mothers showed less negative change (less increase in frowning) in their behavior during the non-contingent replay segment. This finding was interpreted as the infants of depressed mothers being more accustomed to non-contingent behavior in their mothers, thus experiencing less violation of expectancy in this situation.     

Effects of adults’ contingent responding on infants’ behavior in ambiguous situations

We examined the effect of adults’ contingency in responding to infants’ behavior in an ambiguous situation in two experiments. In Experiment 1, forty-four 12-month-old infants were exposed to an ambiguous toy. An unfamiliar adult responded either contingently or non-contingently to the infant’s bids and then presented the toy and provided positive information. During toy presentation, infants in the non-contingent condition looked less at the experimenter than infants in the contingent condition. In a concluding free-play situation infants in the non-contingent condition played less and tended to touch the toy less. In Experiment 2 (forty-four 12-month-old infants), the parent either responded promptly or with a delay each time the infant made contact initiatives and then presented an ambiguous toy and delivered the positive information. The infants in the non-contingent condition tended to look less at the parent during toy presentation and also tended to play less with the toy during the concluding free-play situation. The findings show that adults’ contingency in responding influences infants’ behavior in ambiguous situations.     

Does contingency in adults’ responding influence 12-month-old infants’ social referencing?

In two experiments we examined the influence of contingent versus non-contingent responding on infant social referencing behavior. EXPERIMENT 1: Forty 12-month-old infants were exposed to an ambiguous toy in a social referencing situation. In one condition an unfamiliar adult who in a previous play situation had responded contingently to the infant’s looks gave the infant positive information about the toy. In the other condition an unfamiliar adult who previously had not responded contingently delivered the positive information. EXPERIMENT 2: Forty-eight 12-month-old infants participated in Experiment 2. In this experiment it was examined whether the familiarity of the adult influences infants’ reactions to contingency in responding. In one condition a parent who previously had responded contingently to the infant’s looks provided positive information about the ambiguous toy, and in the other condition a parent who previously had not responded contingently provided the positive information. The infants looked more at the contingent experimenter in Experimenter 1, and also played more with the toy after receiving positive information from the contingent experimenter. No differences in looking at the parent and in playing with the toy were found in Experiment 2. The results indicate that contingency in responding, as well as the familiarity of the adult, influence infants’ social referencing behavior.     

Does contingency in adults’ responding influence 12-month-old infants’ social referencing?

In two experiments we examined the influence of contingent versus non-contingent responding on infant social referencing behavior. EXPERIMENT 1: Forty 12-month-old infants were exposed to an ambiguous toy in a social referencing situation. In one condition an unfamiliar adult who in a previous play situation had responded contingently to the infant’s looks gave the infant positive information about the toy. In the other condition an unfamiliar adult who previously had not responded contingently delivered the positive information. EXPERIMENT 2: Forty-eight 12-month-old infants participated in Experiment 2. In this experiment it was examined whether the familiarity of the adult influences infants’ reactions to contingency in responding. In one condition a parent who previously had responded contingently to the infant’s looks provided positive information about the ambiguous toy, and in the other condition a parent who previously had not responded contingently provided the positive information. The infants looked more at the contingent experimenter in Experimenter 1, and also played more with the toy after receiving positive information from the contingent experimenter. No differences in looking at the parent and in playing with the toy were found in Experiment 2. The results indicate that contingency in responding, as well as the familiarity of the adult, influence infants’ social referencing behavior.     

Contingency effects with maintained instrumental reinforcement

In three experiments we investigated the effect on the performance of thirsty rats of varying the instrumental contingency between lever pressing and the delivery of a saccharin reinforcer. In Experiment 1, the subjects performed more slowly in a non-contingent condition, in which the momentary probability of reinforcement was unaffected by whether or not the animals pressed, than in a contingent condition in which the reinforcer was never presented except following a lever press. This was true of performance under both random ratio and interval schedules in which the function determining the probability of reinforcement following a lever press remained the same across the contingent and non-contingent conditions. Experiment 2 demonstrated that instrumental performance was less affected when the contingency was degraded by the introduction of free reinforcers if these reinforcers were signalled. In Experiment 3, lever pressing was reinstated to some degree after non-contingent training by giving non-reinforced exposure to the operant chamber in the absence of the lever. These results suggest that free reinforcers depress instrumental behaviour through a performance mechanism engaged by their ability to support conditioning of the contextual cues.     

Development of sensitivity to information for impending collision

Infants were tested in three experiments to study the development of sensitivity to information for impending collision and to investigate the hypothesis that postural changes of very young infants in response to an approaching object are of a tracking rather than of a defensive nature. Experiment 1 involved the presentation of three types of shadow projection displays, specifying (1) collision, (2) noncollision, and (3) a nonexpanding rising contour, to infants from 1 to 9 months of age. Avoidance of collision appears to be absent in 1- to 2-month-olds, begins to develop in 4- to 6-month-olds, and is present in 8- to 9-month-old infants. In Experiment 2, 1- to 2-month-old infants were presented with optical expansion patterns which specified collision and noncollision. The top contour of these displays stayed at eye level. No significant difference was observed between reaction to the collision and the noncollision displays, suggesting that the young infants were tracking the displays and not attempting to avoid collision. Experiment 3 was designed to determine whether an approaching real object might elicit an avoidance response in infants not sensitive to an optical display specifying collision. No evidence of avoidance behavior was observed in the 1- to 2-month-olds; however, avoidance, as indexed by blinking, does appear to be present at 4 months of age.     

No evidence for infants’ contingency detection as a precursor of toddlers’ self-recognition

The aim of the present study was to assess the relationship between infants’ contingency preference and detection in the first year of life and toddlers’ mirror and video self-recognition in the second and third year of life in a longitudinal study (N = 113). Six- and 9-month-olds’ preference for a noncontingent over a perfect contingent view (contingency preference) and their differentiation between the two views – indicated by longer looking times to either view – (contingency detection) were assessed in two contingency tasks. A mirror-face-recognition task and a mirror-leg-recognition task were conducted at 18 months. A video-face-recognition task and a mirror-leg-recognition task were conducted at 26 months. Results revealed no predictive relationships between infants’ contingency preference and detection in the first year of life and their ability to recognize themselves in a mirror or on a video monitor in the second and third year of life. This finding supports the notion that self-recognition emerges independently from the experience of contingencies (Bischof-Köhler, 1991, 2012). Thus, a representation of the self seems to rely on more than a specific developmental pathway leading from contingency preference and detection to self-recognition.     

Two-month-old infants of depressed mothers show mild, delayed and persistent change in emotional state after non-contingent interaction

The aim of this study was to explore how early infants show different responses to non-contingent maternal behavior according to their past history of relations with their mother. Two groups of 2-month-olds interacted with their mother who was assessed as depressed (group 1) or non-depressed (group 2). Although they received a continuous image and voice of their mothers, the infants were presented either a 30-s contingent maternal communication (live episode 1) or a thirty second non-contingent episode (replay of prior maternal communication), or again a 30-s contingent live episode (live2). The lower percentage of negative facial expressions displayed during replay by infants of depressed mothers suggests on one hand that they are less sensitive to a non-contingent maternal behavior than infants of non-depressed mothers. However, within group comparisons demonstrate a notable difference: while infants of non-depressed mothers show a U curve of smile, infants of depressed mothers show decreasing smile throughout the three episodes. Taken together, these results plead in favour of an other profile of sensitivity displayed by infants of depressed mothers. Instead of the strong but short-term reaction of infants of non-depressed mothers, the response of infants of depressed mothers appeared to be a mild, delayed and more persistent change in emotional state. These findings are discussed in the light of possible cognitive and social incidence of passive avoidance of stressful events in infants of depressed mothers.     

Evidence of amodal representation of small numbers across visuo-tactile modalities in 5-month-old infants

Two experiments investigated 5-month-old infants’ amodal sensitivity to numerical correspondences between sets of objects presented in the tactile and visual modes. A classical cross-modal transfer task from touch to vision was adopted. Infants were first tactually familiarized with two or three different objects presented one by one in their right hand. Then, they were presented with visual displays containing two or three objects. Visual displays were presented successively (Experiment 1) or simultaneously (Experiment 2). In both experiments, results showed that infants looked longer at the visual display which contained a different number of objects from the tactile familiarization phase. Taken together, the results revealed that infants can detect numerical correspondences between a sequence of tactile and visual stimulation, and they strengthen the hypothesis of amodal and abstract representation of small numbers of objects (two or three) across sensory modalities in 5-month-old infants.     

Roughness perception during the rubber hand illusion

Watching a rubber hand being stroked by a paintbrush while feeling identical stroking of one’s own occluded hand can create a compelling illusion that the seen hand becomes part of one’s own body. It has been suggested that this so-called rubber hand illusion (RHI) does not simply reflect a bottom–up multisensory integration process but that the illusion is also modulated by top–down, cognitive factors. Here we investigated for the first time whether the conceptual interpretation of the sensory quality of the visuotactile stimulation in terms of roughness can influence the occurrence of the illusion and vice versa, whether the presence of the RHI can modulate the perceived sensory quality of a given tactile stimulus (i.e., in terms of roughness). We used a classical RHI paradigm in which participants watched a rubber hand being stroked by either a piece of soft or rough fabric while they received synchronous or asynchronous tactile stimulation that was either congruent or incongruent with respect to the sensory quality of the material touching the rubber hand. (In)congruencies between the visual and tactile stimulation did neither affect the RHI on an implicit level nor on an explicit level, and the experience of the RHI in turn did not cause any modulations of the felt sensory quality of touch on participant’s own hand. These findings first suggest that the RHI seems to be resistant to top–down knowledge in terms of a conceptual interpretation of tactile sensations. Second, they argue against the hypothesis that participants own hand tends to disappear during the illusion and that the rubber hand actively replaces it.     

Visual self-recognition in mirrors and live videos: Evidence for a developmental asynchrony

Three experiments (N = 123) investigated the development of live-video self-recognition using the traditional mark test. In Experiment 1, 24-, 30- and 36-month-old children saw a live video image of equal size and orientation as a control group saw in a mirror. The video version of the test was more difficult than the mirror version with only the oldest children's performance approaching ceiling. In Experiment 2, most 24-month-olds showed self-recognition when presented with a TV-set that featured a mirror in place of a screen. This finding does not substantiate the possibility that expectations about what appears on TV are responsible for the asynchrony. In Experiment 3, children were given a mark-test involving only their legs. Again, a video version was more difficult than previously reported performance with mirrors, suggesting that the impossibility of eye-contact in video cannot explain this developmental asynchrony. The findings suggest that self-recognition can be added to the growing list of contexts in which 2-year-olds display what has been called a “video deficit” [Anderson, D. R., & Pempek, T. A. (2005). Television and very young children. American Behavioral Scientist, 48, 505–532].     

Irrelevant incentive learning during instrumental conditioning: The role of the drive-reinforcer and response-reinforcer relationships

Four experiments investigated the processes by which a motivationally-induced change in the value of the training reinforcer affects instrumental performance. Initially, thirsty rats were trained to lever press for either a sodium or non-sodium solution. In Experiment I sodium-trained rats responded faster in extinction following the induction of a sodium appetite, but not following either food or water deprivation. Thus, enhanced extinction performance depends upon the relevance of the training reinforcer to the test drive state. The remaining experiments examined the role of the instrumental contingency. Animals received response-contingent presentations of one solution alternated either within (Experiments II and III) or between sessions (Experiment IV) with non-contingent presentations of another solution. Neither procedure yielded convincing evidence that contingent sodium presentations generated more responding in extinction under a sodium appetite than did non-contingent sodium presentations. On the basis of these results, we argue that the instrumental contingency itself does not play a major role in this irrelevant incentive effect.     

When do infants expect hands to be connected to a person?

A violation-of-expectation paradigm was used to test whether infants infer a person based on the presence of hands alone. Infants were familiarized to a pair of hands that extended out from a curtain to play with a rattle, after which the curtain was opened to reveal either a real person or a mannequin. Infants’ looking at these outcomes was compared with baseline looking at the person and the mannequin. Experiment 1 showed that 9-month-olds looked significantly longer at the mannequin than at the person after familiarization to hands. Experiment 2 ruled out a low-level feature matching interpretation by showing the same looking pattern in 9-month-olds even when the hands were covered with silver gloves. In Experiment 3, 6-month-olds showed no differential looking at the mannequin and person after familiarization to hands. Taken together, these experiments suggest that infants acquire the expectation that hands are connected to a person between 6 and 9 months of age. This finding has implications for how infants’ attribute goals to manual actions.     

The development of infants' preference for motherese

Generally, infants prefer infant-directed (ID) to adult-directed (AD) speech. Mostly, researchers have used unfamiliar female voices in these studies. We investigated preferences for maternal ID speech in 1- and 4-month-olds. Using a procedure in which infants controlled access to voices by fixating a visual display, infants listened to recordings of natural female ID and AD speech. In Experiment 1, 1-month-olds heard recordings of maternal ID and AD speech, but these infants showed no preference for maternal ID speech. In Experiment 2, 1-month-olds heard the same ID and AD speech tapes but were not familiar with the speakers. Contrary to Experiment 1, these infants preferred ID speech. In Experiment 3, 4-month-olds heard recordings of maternal ID and AD speech and showed a significant preference for ID speech. Collectively, these results suggest that infant attention to ID speech depends on both speaker-general and speaker-specific characteristics, with interesting developmental changes occuring during early infancy.     

Infant perceptual and conceptual categorization: the roles of static and dynamic stimulus attributes

Infants' categorization of animals and vehicles based on static vs. dynamic attributes of stimuli was investigated in five experiments (N=158) using a categorization habituation-of-looking paradigm. In Experiment 1, 6-month-olds categorized static color images of animals and vehicles, and in Experiment 2, 6-month-olds categorized dynamic point-light displays showing only motions of the same animals and vehicles. In Experiments 3, 4, and 5, 6- and 9-month-olds were tested in an habituation-transfer paradigm: half of the infants at each age were habituated to static images and tested with dynamic point-light displays, and the other half were habituated to dynamic point-light displays and tested with static images. Six-month-olds did not transfer. Only 9-month-olds who were habituated to dynamic displays showed evidence of category transfer to static images. Together the findings show that 6-month-olds categorize animals and vehicles based on static and dynamic information, and 9-month-olds can transfer dynamic category information to static images. Transfer, static vs. dynamic information, and age effects in infant categorization are discussed.     

Rapid word learning in 13- and 17-month-olds in a naturalistic two-word procedure: looking versus reaching measures

This study investigated infants’ rapid learning of two novel words using a preferential looking measure compared with a preferential reaching measure. In Experiment 1, 21 13-month-olds and 20 17-month-olds were given 12 novel label exposures (6 per trial) for each of two novel objects. Next, in the label comprehension tests, infants were shown both objects and were asked, “Where’s the [label]?” (looking preference) and then told, “Put the [label] in the basket” (reaching preference). Only the 13-month-olds showed rapid word learning on the looking measure; neither age group showed rapid word learning on the reaching measure. In Experiment 2, the procedure was repeated 24 h later with 10 participants per age group from Experiment 1. After a further 12 labels per object, both age groups now showed robust evidence of rapid word learning, but again only on the looking measure. This is the earliest looking-based evidence of rapid word learning in infants in a well-controlled (i.e., two-word) procedure; our failure to replicate previous reports of rapid word learning in 13-month-olds with a preferential reaching measure may be due to our use of more rigorous controls for object preferences. The superior performance of the younger infants on the looking measure in Experiment 1 was not straightforwardly predicted by existing theoretical accounts of word learning.     

Affective facial expression in sub-clinically depressed and non-depressed mothers during contingent and non-contingent face-to-face interactions with their infants

BackgroundDepression in the postpartum period involves feelings of sadness, anxiety and irritability, and attenuated feelings of pleasure and comfort with the infant. Even mild- to- moderate symptoms of depression seem to have an impact on caregivers affective availability and contingent responsiveness. The aim of the present study was to investigate non-depressed and sub-clinically depressed mothers interest and affective expression during contingent and non-contingent face-to-face interaction with their infant.MethodsThe study utilized a double video (DV) set-up. The mother and the infant were presented with live real-time video sequences, which allowed for mutually responsive interaction between the mother and the infant (Live contingent sequences), or replay sequences where the interaction was set out of phase (Replay non-contingent sequences). The DV set-up consisted of five sequences: Live1-Replay1-Live2-Replay2-Live3. Based on their scores on the Edinburgh Postnatal Depression Scale (EPDS), the mothers were divided into a non-depressed and a sub-clinically depressed group (EPDS score ≥ 6).ResultsA three-way split-plot ANOVA showed that the sub-clinically depressed mothers displayed the same amount of positive and negative facial affect independent of the quality of the interaction with the infants. The non-depressed mothers displayed more positive facial affect during the non-contingent than the contingent interaction sequences, while there was no such effect for negative facial affect.ConclusionsThe results indicate that sub-clinically level depressive symptoms influence the mothers’ affective facial expression during early face-to-face interaction with their infants. One of the clinical implications is to consider even sub-clinical depressive symptoms as a risk factor for mother-infant relationship disturbances.     

The effect of social feedback contingent upon a non-social response in seven- and ten-month-old infants

Summary Acquisition of a manipulative response under contingent and non-contingent maternal social stimulation was examined in seven- and ten-month-old infants. Response acquisition was reliably deomonstrated in the case of the ten-month-old infants, but not in the case of the seven-month-old infants. However, despite no acquisition, the performance of the younger infants did differ from that obtained under non-contingent scheduling Examination of visual behaviour to the manipulandum and the feedback source revealed comparable profiles for both ages. The findings are interpreted in terms of the greater difficulty of mixed social/non-social contingency situations and discussed in the context of cognitive constraints on response acquisition in infancy.The conduct of this study was supported by a grant from the United Kingdom Social Science Research Council to H.R. Schaffer, and undertaken whilst the author was a Research Fellow in Psychology at the University of Strathclyde, Glasgow, Scotland.The author is grateful to W.M. Cheyne for advice and to Norman Sharp and Margaret Hunter who assisted with the data collection and analysis.     

Two are better than one: comparison influences infants' visual recognition memory

Despite a large literature on infants’ memory for visually presented stimuli, the processes underlying visual memory are not well understood. Two studies with 4-month-olds (N = 60) examined the effects of providing opportunities for comparison of items on infants’ memory for those items. Experiment 1 revealed that 4-month-olds failed to show evidence of memory for an item presented during familiarization in a standard task (i.e., when only one item was presented during familiarization). In Experiment 2, infants showed robust memory for one of two different items presented during familiarization. Thus, infants’ memory for the distinctive features of individual items was enhanced when they could compare items.     

The role of the response-reinforcer contingency in negative automaintenance

When a response key is briefly illuminated before a grain reinforcer is presented, key pecking is reliably developed and maintained in pigeons, even if pecking prevents reinforcement (negative automaintenance). This experiment demonstrated that pigeons are sensitive to a negative response-reinforcer contingency, even though it does not eliminate responding. Within individual pigeons, two kinds of trials were compared: red key trials, in which reinforcement was negatively contingent on responding, and white key trials, in which reinforcement was unrelated to responding. Reinforcement frequency in non-contingent trials was yoked to the obtained reinforcement frequency in negatively contingent trials. All eight pigeons pecked substantially more on the non-contingent key than on the negative key, and preferred the non-contingent key to the negative key on occasional “choice” trials where both were presented together. When the stimuli correlated with the two conditions were reversed, the pigeons' behavior also shifted. These response differences are taken as evidence that pigeons are sensitive to the negative response-reinforcer contingency.