Word Order Rules: Parsing Sentences in a “Free” Word Order Language

In fixed word order languages like English, word order is highly predictive of a noun\u27s thematic and grammatical role, and a large body of research has shown that speakers of fixed word order languages tend to rely on word order when they parse and interpret sentences. In flexible word order languages like Turkish, word order is less predictive of nouns\u27 thematic and grammatical roles, and less is known about the types of cues adult speakers use to determine the meaning of sentences. How do speakers of free word order languages determine the grammatical role of nouns? To answer this question, we presented 28 adult speakers of Turkish 48 stimuli sentences where the word order was varied between SOV and OVS. The cues to aid the grammatical roles were word order, casemarking on the object noun, and when a casemarker was not present an indefinite determiner. The results suggest that, of the three morphosyntactic cues (word order, overt-casemarking, and determiner), word order is the primary cue that Turkish speakers use to assign grammatical and thematic roles, overt object casemarking is a strong secondary cue, and the indefinite determiner is a weaker tertiary cue

The Relationship between Phoneme Production and Perception in Speech-Impaired and Typically-Developing Children

One of the central questions that Eric Lenneberg raised in his seminal book, Biological Foundations of Language is: What is the relationship between language comprehension and language production? This paper reviews Lenneberg’s case study of a child with congenital anarthria and then presents the results of two studies that investigate the relationship between phoneme perception and production. The first study investigates the phoneme identification skills of a child with developmental apraxia who, like the anarthric child studied by Lenneberg, had essentially no speech yet had no difficulty understanding speech. The second study investigates the extent to which 28 typically-developing children’s ability to identify phonemes is related to their ability to produce phonemes. The results of both studies support Lenneberg’s conclusion that children’s ability to perceive speech is not dependent on their ability to produce speech. Thus, Lenneberg’s original case study and the two studies presented in this paper argue against gestural theories of speech perception such as the Motor Theory

Comprehending Turkish sentences using word order, thematic roles, and case

A core aspect of sentence comprehension is assigning thematic roles such as agents and patients to nouns. Turkish, a flexible word order language with accusative case-marking, allows us to compare the relative effect of word order, case-marking, and thematic reversibility in sentence comprehension. We conducted two spoken language comprehension experiments to investigate the relationships among these factors. Native Turkish-speaking adults were faster and more accurate in comprehending sentences with default word order than those with scrambled word order; case-marked sentences than non-casemarked sentences; and sentences with thematically irreversible nouns than those with reversible nouns. The effect of word order depended on the reversibility of the nouns, and case-marking had little-to-no effect on comprehension when the nouns were thematically irreversible. Our results suggest that while Turkish speakers use multiple cues to map thematic roles onto nouns, there are diminishing returns of facilitation with each additional source of information. These results give support to race-based models of sentence comprehension

The Relationship between Phoneme Production and Perception in Speech-Impaired and Typically-Developing Children

One of the central questions that Eric Lenneberg raised in his seminal book, Biological Foundations of Language is: What is the relationship between language comprehension and language production? This paper reviews Lenneberg’s case study of a child with congenital anarthria and then presents the results of two studies that investigate the relationship between phoneme perception and production. The first study investigates the phoneme identification skills of a child with developmental apraxia who, like the anarthric child studied by Lenneberg, had essentially no speech yet had no difficulty understanding speech. The second study investigates the extent to which 28 typically-developing children’s ability to identify phonemes is related to their ability to produce phonemes. The results of both studies support Lenneberg’s conclusion that children’s ability to perceive speech is not dependent on their ability to produce speech. Thus, Lenneberg’s original case study and the two studies presented in this paper argue against gestural theories of speech perception such as the Motor Theory

On-line processing of English which-questions by children and adults: a visual world paradigm study

Previous research has shown that children demonstrate similar sentence processing reflexes to those observed in adults, but they have difficulties revising an erroneous initial interpretation when they process garden-path sentences, passives, and wh -questions. We used the visual-world paradigm to examine children's use of syntactic and non-syntactic information to resolve syntactic ambiguity by extending our understanding of number features as a cue for interpretation to which -subject and which -object questions. We compared children's and adults’ eye-movements to understand how this information shapes children's commitment to and revision of possible interpretations of these questions. The results showed that English-speaking adults and children both exhibit an initial preference to interpret an object- which question as a subject question. While adults quickly override this preference, children take significantly longer, showing an overall processing difficulty for object questions. Crucially, their recovery from an initially erroneous interpretation is speeded when disambiguating number agreement features are present

Neutron experiments at Portsmouth for measuring flow and {sup 235}U content in UF{sub 6} gas

The Portsmouth Gaseous Diffusion Plant produces enriched uranium for use in commercial power reactors. The plant also aids disposal of excess high-enrichment uranium (HEU) by blending it with lower-enrichment material. Experiments were conducted to test two neutron-based methods for monitoring the down-blending of HEU. Results of the initial experiments showed that gas (on-off) could be detected, but that additional tests and data are needed to quantify the flow velocity and {sup 235}U content. The experiments used a {sup 252}Cf neutron source to induce fission in a small fraction of the {sup 235}U contained in the UF{sub 6} gas. The first method measured the attenuation of neutrons passing through the low-pressure UF{sub 6} gas in a 7.6-cm diameter pipe. The concept was based on the fact that some of the thermal neutrons are absorbed by {sup 235}U, thus changing the observed count rate. The second method, tested on a 20-cm diameter pipe where gas pressure was higher, used a modulated neutron flux to induce fission in the {sup 235}U. Modulation was achieved by moving a neutron source. During both experiments, plant monitoring equipment showed that light gases (freon, oxygen, and nitrogen) were present in widely varying amounts, along with the UF{sub 6} gas. These gases may have affected the experimental results, at least to the extent that they replaced UF{sub 6}. This report also contains results of computer simulations and tests performed on the electronics after the experiments were completed at Portsmouth. Recommendations are made for follow-on work to measure the flow velocity and {sup 235}U content

Boron-Lined Straw-Tube Neutron Detector Test

Radiation portal monitors used for interdiction of illicit materials at borders include highly sensitive neutron detection systems. The main reason for having neutron detection capability is to detect fission neutrons from plutonium. The currently deployed radiation portal monitors (RPMs) from Ludlum and Science Applications International Corporation (SAIC) use neutron detectors based upon 3He-filled gas proportional counters, which are the most common large neutron detector. There is a declining supply of 3He in the world, and thus, methods to reduce the use of this gas in RPMs with minimal changes to the current system designs and sensitivity to cargo-borne neutrons are being investigated. Four technologies have been identified as being currently commercially available, potential alternative neutron detectors to replace the use of 3He in RPMs. Reported here are the results of tests of a boron-lined proportional counter design variation. In the testing described here, the neutron detection efficiency and gamma ray rejection capabilities of a system manufactured by Proportional Technologies, Inc, was tested