Sentences of Note:, "Early in development, infants begin to use symbols to refer to objects, actions, and events in the world.", A. "Early in development" is not a particularly precise stage of development., "Language learning requires more complex abilities than learning a simple symbol-to-referent mapping"., Symbolic comparison is not innately more complicated than linguistic comparison., "distinction between language acquisition and symbol development is less clear at the point when infants start to produce words.", Next: "Infant's initial strides in word acquisition involve predominantly learning to make word-to-referent mappings." Furthermore, "...early word acquisition focuses on the symbolic nature of words.", But then: "this developmental fact leads to the primary focus of the article, how the general ability to learn symbols relates to word acquisition early in language development.", "A review of RECENT LITERATURE (?) leads us to consider the possibility that early word acquisition is a function of a general symbolic ability, implying that infants would learn words and other symbolic forms with equal facility at the onset of word acquisition.", Sentence preceding this: "Much of the literature on early word-learning has made the assumption that the processes underlying word acquisition are unique to words from the onset of acquisition." (then, throws in a list of citations).
"Goal of the Study", "To examine extent to which infants distinguish between words and other types of symbols, and how the distinction between word-learning and other symbolic behaviors might change with development."
Acredolo and Goodwyn, Goal/Hypothesis, To "assess directly the relation between word-learning and other symbolic communication at the onset of productive language.", Subjects, Participants ranging from 11 to 24 Months of Age., Methods, Methods were not discussed..., Results, Over 85% of infants used symbolic gestures (as well as words) to label, request and express an intention to retrieve or search for objects., Gestures typically extracted from ritualized routines, extended to novel instances and to novel concepts., Infants appeared to use symbolic gestures in ways that were virtually identical to the way they employed words., Infants tended to produce their first symbolic gestures at around the same time that words are produced.
Iverson, Capirici and Caselli, Findings, At 16 months, infants used both words and symbolic gestures to name objects., At 20 months, infants ceased to use symbolic gestures as names for object categories., "Over time, word learning diverges from symbol use more generally. Words take on a privileged status in the infant's communicative repertoire.
"Hypothesis", "An early, general ability to learn symbols gives rise to a more unique focus on words, later in development.", "Younger infants will be equally likely to learn words and gestures as names for object categories, but older infants will be more likely to interpret words than gestures as names for object categories."
"Subjects", Two Age Groups, "18-month-olds: who are still in the single-word utterance stage and still use symbolic gestures.", 26-month-olds: have begun to combine words and for whom the the use the use of symbolic gestures has declined.
"Method", "Forced-Choice Categorization", Two Subordinate Level Categories introduced to Children., Fruit, Vehicle, Infants assigned to one of three groups:, Novel Word, Word condition hear members of the target category (e.g. orange and apple) labeled under a novel word., Novel Gesture, Gesture condition see category members labeled with a novel, non-iconic gesture., No Symbol, Shown the objects with no label at all., "Infants introduced to novel words in such tasks focus more attention on object categories than do children in no-word control conditions.", Infants then asked to choose between an additional category member (eg. a pair) and an unrelated distractor (eg. a chair) as a match for one of the target objects., How is this measuring the contruct in question here? It's just measuring the similarities and differences with the objects themselves, not the ability to use symbols., The Determinant Questions:, 1. If infants recruit both words and symbolic gestures as names for object categories, then infants in both the word and gesture conditions should select category members more frequently than infants in the No Symbol condition., 2. If infants more readily interpret words than gestures as names for object categories, we should find that those in the Word condition select category members more frequently than those in either the Gesture or No Symbol condition.
Author uses terms that are not operationally defined; uses factual sentence structure when referring to something which is not innately true.
Author seems to have structured sections of this article illogically. Most articles of substance use the following construction: INTRO TO SUBJECT -> THOUGHTS OF FIELD -> YOUR THOUGHTS/HYPOTHESIS. This skips between all three in a method which makes overall comprehension of this piece quite difficult.
Author makes claims to certain things, but does not cite the sources of those claims.
The control condition is relatively vague. It isn't controlling for anything.
This is not a proper test. A proper test is comparing two things, a "Yes" and a "No". This is comparing three things: a "yes", a "also yes", and a "no". You can't make legitimate conclusions with this test.
Note 1: The author is using children who already fit his hypothesis as his second subject group - "Kids who don't use physical signs." Note 2: The point of comparision being utiliized is comparatively focused on development timelines. The design should have analyzed children over a period of time.
Subjects, 48 children of 18 months (M age = 17.9, range = 16.8-18.6), Only included infants who were not yet combining words (parental report)., Exclusions: 15 infants excluded for three reasons:, (1) Experimenter Error (???), (11) Failure to complete the task, (3) Failure to make enough clear choices, 7 exclusions in the word condition, 6 in the gesture condition, 1 was in the no-symbold condition., 48 Children of 26 months (M = 25.9, range = 25.1 - 26.7), Only included infants who had begun to combine words., Three 26-month olds were excluded due to failure to complete the task.
Stimuli, 26 Plastic Toy Replicas of Objects., Two sets of 13. Each set had:, 7 Members of a Superordinate Level target category (fruit, vehicle), 6 Unrelated Distractor Items, One item was presented as the "target stimuli". Then, each similar stimuli was paired with one that was not similar., Two of the similar items were designated as "near" (very similar to the target item), two were designated as "intermediate", and two were "far"., Allows for a more in-depth analysis of infant's patterns of extension.
Procedure, Constants:, 1. Playroom, 2. Positioning (sat directly across experimentor), 3. Caregivers asked not to help at all., 4. Infants randomly assigned to each test group., Phases, 1. Warm-Up Phase, Purpose: "to familiarize the infants briefly with the type of symbolic input they would receive during the experiment proper., For Infants in the "No Symbol" condition, experimenter pointed to the unfamiliar object saying "Look at that one! See that!", For Infants in the "Word" condition, experimenter pointed to the object and labeled it with a novel word: "We call this a [word]! See the [word]?" Then, child is asked: "Can you give me the [word]?", For Infants in the "Gesture" condition, experimenter pointed to the object and labeled it with a novel gesture: "We call this a [gesture]! See the [gesture]?" Then, child is asked: "Can you give me the [gesture]?", Gestures were selected to be arbitrary, easily replicable by infants., After the Phase was over, the object was removed., 2. Introduction Phase, Purpose: "to introduce the infants to the target category.", Two objects presented to the infant: the "target object" and an object in the "near" category., Attention drawn to each of the two objects five times, while the infant played freely with the objects. Manner which the experimenter referred to the object varies per condition., Words: "We call this a [word]!" and "Look at this [word]!", Gestures: "We call this one [gesture]!" and "Look at this [gesture]!", No Symbol: "Look at this one!" and "Do you like this one?", 3. Test Phase, For each category, there were six test trials. One target object, another member of the target category, and an unrelated distractor., Infant played with the object for 15s. Then, they removed the three objects. Finally, the child's focus was put on the object, and then the infant was asked to select between the two test objects., Words: "Look at the [word]. Can you find me another [word]?", Gestures: "Look at the [gesture]. Can you find me another [gesture]?", No Symbol: "Look at this one! Can you find me another one?", Two types of Test Trials for Each Category:, (1) Mapping Trial: Category choice was one of the two objects that had been previously labeled during the introduction phase., Determined whether the infants had made the pairing between the symbol and it's referent., (2) Extension Trials, done 5 Times: category choices were novel instances of the target category., Examines the infant's willingness to extent a symbol beyond the instances upon which it was taught, so as to derive a clear picture of infants extension patterns.
Coding, Three possible outcomes on each trial:, 1. Selecting the correct category member., 2. Selecting the distractor., 3. Making no clear choice., Any infant who failed to make a clear choice on more than two out of 12 trials was excluded., Coding agreement, in accordance to the Kappa Statistic, is extremely high: (k=.9575, p < 0.001)
Results, (1) Infants in the "word" condition were more likely to select category members than those in either the "Gestural" or "No Symbol" categories., This trend was observed in both 18 and 26-Month olds. However, there is a clear difference in performance with regards to age., At 18 Months, infants in the Gesture Condition, like the Word Condition, were significantly more likely to select category choices than those in the Word condition., 18-month-olds selected the category members that exceed chance in both the Word and Gesture categories., At 26 Months, the Gesture Condition was much less likely to select category choices than those in the Word condition., 26-month-olds selected the category members more frequently in the word category (than predicted by chance), but those in the gesture and no symbol conditions did not differ reliably., (2) 26-Month Olds were more likely to select the category members on mapping trials than extension trials., There was no effect of trial type on 18-month-old infants' performance in any condition., (3) 18-month-olds performed better on the fruit than on the vehicle category., There was no effect on 26-year-olds on target category., (4) Infants were most likely to select category members when they were perceptually more similar to the target., (5) Infants of 18 Months in the upper third of correct answers did not differ between the two conditions. But 26 Months the number of infants in the upper third did differ, higher mean rates of category responded in the word category - the result of consistent differences.
Discussion, 1. 18 Months would apply novel symbols to object categories in both Word and Gesturial., 2. 26 Months would do so in the word, but not the gesturial., This is striking - older infants fail to reveal a symbolic capacity to learn gestures while younger infants succeed., 1. The older infants' failure to interpret gestures as names for object categories may be related to the fact that the gestures were embedded within a spoken language., 2. Infants may become more conservative, with age and experience, about what types of symbols that they will take to refer to objects.
Introduction, Goal: "To teach 2-year olds that a Gesture, like a word, may be used to name an object.", Methodology: "Symbols introduced within the context of a familiar naming routine.", A puppet used to identify objects using either a Word, Gesture or a simple point., Reasoning:, 1. Permits us to remove the symbols from a sentence frame., 2. Because gestures are embedded in a familiar naming routine, this method may encourage the infants to overcome their conservative stance with respect to gestures.
Method, Participants:, 36 27-month-old infants recruited from the same population used in Experiment 1., Because only 5% of the 26-month-olds contacted for Experiment 1 were not yet combining words, we did not include this specific selection criterion in Experiments 2 and 3, 7 Additional infants were excluded from the analysis because of:, (2) Equipment Failure, (4) Failure to complete the task, (1) Failure to make enough clear choices, Two were in the word condition, four in the gesture condition, and one was in the no-symbol condition., Stimuli:, 26 Toy Replicas of objects., As in Experiment 1, each set was composed of seven members of the target category (fruit or vehicle) and six unrelated distractors., Puppet (Charlie the Cricket), stuffed animal sewn to the back of a glove. Ideally suited to perform any gesture that can be performed by a human hand., Procedure, Constants:, 1. Playroom, 2. Positioning (sat directly across experimentor), 3. Caregivers asked not to help at all., 4. Infants randomly assigned to each test group., Assignment:, Infants randomly assigned to either a Word, Gesture, or No Symbol condition., Phases, Warm-Up Period:, Purpose: "To familiarize the infants with the puppet and introduce them to the type of symbolic input they would receive., Experimenter introduced infants to the puppet, permitted infant and puppet to interact briefly., Word Condition: "Charlie speaks a different language, so he has a special name for things.", Gesture Condition: "Charlie can't talk, but he uses his hands to speak.", No Symbol Condition: infants not given any information about Charlie., Introduction Phase:, Word Condition: "Charlie calls attention to the word. Charlie repeats the word, experimentor repeats the word, infant is encouraged to repeat the word. Word is then applied to both objects of each category.", Gesture Condition: "Charlie labels objects by focusing attention on an object, then performing a series of gestures. Experimenter repeats gestures, encourages infant to repeat gestures. Gesture is applied to both objects of each category.", Test Phase: