Aspartame and Energy Essay

Submitted By katwoman132
Words: 1113
Pages: 5

Speech Perception
The first research article, titled ‘Developmental Aspects of Cross-Language Speech Perception’ by Werker, Gilbert, Humphrey and Tees (1981), examines infant and adult abilities to discriminate phonemes across languages. This means that minor acoustic differences in speech sounds should be ignored. The study was built on evidence from previous studies that categorization of speech is a built in ability within humans. This study was the first to include both infants and adults as participants (Werker et al., 1981). Four groups were tested in a ‘discrimination paradigm’ on two pairs of Hindi linguistic sounds. Group one was made up of five Hindi-speaking adults. Group two consisted of fifteen infants, with an average age of six months, twenty-eight days. Group three and four each contained ten English-speaking adults with no prior experience with the Hindi language. Group four was given training trials. This was done so the English speaking adults could be compared with the infants. One English stimulus pair and two Hindi stimuli pairs were utilized. Werker et al. (1981), explain that two pairs of Hindi sounds were used to sample two sets of sounds that have different discriminative difficulties. Infants were tested using a ‘visually reinforced infant speech discrimination’ (VRISD) paradigm which involves conditioned head turns when the infant recognizes a change in the speech sound. It was found that six month olds were able to discriminate both Hindi sound pairs. Hindi adults were able to discriminate all sound pairs but English adults could not discriminate one of the Hindi sound pairs and only some English adults could discriminate the other Hindi sound pair. The training given to the fourth group slightly improved their ability to discriminate the less difficult Hindi sound pair but not the difficult Hindi sound pair.
While reading this study, I was truly impressed with the measures that were taken by Werker et al. (1981) to control for many extraneous variables that could have negatively affected the study. There are a few elements of the study that I would change if I were the experimenter. The first and probably most obvious change being the sample size. Although it would be difficult to find a large number of cooperative babies, I think this study deserved a larger sample size. Also, I would have used a more difficult English phoneme to accompany the already existing stimulus pair. It would be interesting to see if the difficulties of the English sounds have an effect on the results, as it was shown that some English speaking adults could actually discriminate between the differences of the ‘easier’ Hindi sound pair. Werker et al. (1981) mentioned that there some studies which found that English infants could not discriminate between some non-English sounds. This would be an interesting aspect to look into. There are many languages in the world and although it would take a while, I think it would be useful.
The second research article, ‘Cross-Language Speech Perception: Evidence for Perceptual Reorganization During the First Year of Life’ by Werker and Tees (1984) consists of two experiments. In the first experiment, Werker and Tees (1984) try determine whether or not the results found in their previous (1981) study are due to developmental changes. The experimental procedure was similar to the other study described, but instead of Hindi, Werker and Tees (1984) used a Canadian Native Indian (Thompson) language. Subjects involved in the study were: twelve infants (average age of six months, twenty-nine days), ten English speaking adults and five Thompson-speaking adults. Thompson adults, English adults and English infants were compared with each other on their ability to discriminate the paired Thompson stimuli. It was found that all the Thompson speaking adults could discriminate the sounds. Three out of ten adult English speakers discriminated the sounds. Eight out of ten of the English infants