This article was about a study carried out to investigate whether younger infants are better in discriminating voices and faces when compared with those older than them. According to Lewkowicz and Ghazanfar (2006), current theoretical views assume that basic intersensory perceptual ability are either present at birth and they become more developed as one grows or they are not present at birth and one only acquires them as he or she adapts to the world. Most researches have however sided with the theory that intersensory perceptual are present at birth and develop with age.
The subjects were groups of 4, 6, 8, and 10 months old infants. The infants were seated 50 cm from a monitor and pairs of monkeys producing two vocalizations were shown to the infants. The study mainly focused on the reaction of the infants when they saw the faces of the monkeys and when they heard their voices. The study involved four trials each lasting one minute. Infants were videotaped during each session and their visual behaviors recorded by an observer who was unaware of the testing conditions. The findings of the study concurred to what the researchers had been expecting. They concluded that younger infants have more voice discriminating abilities than older infants. Therefore, the article describes a successful study that proved that humans exhibit intersensory perceptual. The intersensory perceptual also declines with age.
The topic of the article can easily be understood starting from the tittle. I feel that the article is relevant in learning. First, the results of the study were similar to what most studies had found. The theory that intersensory abilities are not only present at birth but they also develop with age has also been proven in other studies published in various journals. Secondly, the content of the study was clearly shown. The results were clearly explained and then keenly discussed. In addition, the article documented on the recent findings that perceptual development also includes processes that lead into perpetual narrowing which results in reduced processing capacity. Equally, the method used to identify the participant was very efficient because the right age of each infant was identified through their birth records.
The article is however disorganized with the procedure being explained after the results and discussion (p. 4). The procedure was also short and failed to explain some important findings in the results. For instance, it was hard to conclude whether the narrowing in intersensory perceptual observed resulted from the stimulus provided. This is because of the fact that the observers were unaware of the stimulus. The results can also not be relied on since among the infants tested, additional fifty-nine infants had also been tested and had provided no usable data. Therefore, the results could have been inconclusive due to the high number of unused data.
The title of the article reflects on the results of the study being explained in the article. This was very useful in understanding the discussion of the results. The authors acknowledge that intersensory perceptual narrowing are observed early at infancy and also occurs during intersensory development. These findings confirm their earlier predictions that “cross-species intersensory matching of facial and vocal expressions but older infants no longer shows these abilities”. The prediction is similar to those of other researchers, and as such, the results and the predictions were almost similar.
The results were conclusive and concurred with the discussion. In my opinion the study described in the article was successful because the results and the discussion published are similar to what many studies had found. For instance, Simpson et al (2010) proved that and published an article on a similar study that came up with the same results as those of this test. The behavior of the infants seemed to prefer the monkey face that produced a coo face at the beginning of the experiment was taken into account. As a result the researchers were able to compare the time that the infants looked at matching faces in the presence of vocalization and in situations when the vocalization was absent. The discussion however failed to give an explanation as to why the 4-6 months old infants looked at a matching face and the 8-10 infants were unable to identify a matching voice. Instead, the article only discusses the theoretical view that cross-species intersensory is present at birth and continues to develop as the infant grows. The discussion explains broadly the idea that currently the cross-species intersensory perceptual are declining. The article clearly elaborates the findings of the research that observed that there is narrowing in the identification of voices and faces among the infants. Though the results mainly focused on older infants, it was also observed in some young infants.
In my opinion, the data for the six infants discarded because of equipment failure and the other five rejected because of distraction could have been avoided. This was an indication that the experiment was not a total success. In order to have a clear discussion most of the data provided by the infants ought to have matched. Another factor that I feel would have changed the results was the fact that the whole test was based on an assumption that none of the infant had met or seen a monkey before. I find this very unlikely because infants are exposed to an environment where it is not possible to live without seeing animals. For example, the infants could have seen monkeys on televisions or in zoos. The older infants could also have interacted with other animals such as cats and therefore were familiar to the facial expressions of the animals. This could have manipulated the results in favor of the researcher’s predictions.
In conclusion, the article clearly brought out the results and discussions that younger infants are able to discriminate between voice and face than older infants. This is because of the decline in cross-species perceptual in humans as the title of the article suggests. Though the test was successful, the research failed to take certain precautions which I strongly feel could have little to do with the outcome of this experiment. Rather than those few precautions not taken, the article explains of a successful experiment whose results not only agree to other researches that have been carried out but also goes ahead to explain the cause of the decline in cross-species intersensory perceptual in humans. The article therefore concludes that in human intersensory abilities exist. However, these abilities are more developed in early stages of life and continue declining as one grows.
References
Lewkowicz, D.J. and Ghazanfar, A.A. (2006). The decline of cross-species intersensory perception in human infants.
Simpson, E.A., Vagra, K., Frick, J.E., and Fragassszy, D. (2010). Infants Experience Perceptual Narrowing for Nonprimate Faces. Web.