bluuebunny/crossref_metadata_2025 huggingface dataset:
SYNTACTIC AMBIGUITY RESOLUTION IN L2 LEARNERS
Authors: Dussias Paola E.
Published: December 2003

This study investigates whether proficient second language (L2) speakers of Spanish and English use the same parsing strategies as monolinguals when reading temporarily ambiguous sentences containing a complex noun phrase followed by a relative clause, such as Peter fell in love with the daughter of the psychologist who studied in California. Research with monolingual Spanish and English speakers (e.g., Cuetos & Mitchell, 1988) has suggested that, whereas English speakers show a bias to interpret the relative clause locally (i.e., to attach the relative clause to the noun immediately preceding it), Spanish speakers reading Spanish equivalents of English sentences attach the relative clause to the first noun in the complex noun phrase (i.e., nonlocal attachment). In this study, I assess whether speakers whose native language (L1) and L2 differ with respect to processing strategies were able to employ each strategy in the correct context. To this end, L1 Spanish–L2 English and L1 English–L2 Spanish speakers read ambiguous sentences in their L1 and L2. Data collection was carried out using a pencil-and-paper questionnaire and a self-paced reading task. Analyses of both sets of data revealed that both groups of speakers favored local over nonlocal attachment when reading in their L1 and L2. The results are discussed in the context of models that assume the existence of a fixed, universal set of parsing strategies. The implications of L2 parsing research for the field of SLA are also discussed.
EVALUATING THE RELATIVE EFFECTIVENESS OF STRUCTURED-INPUT AND OUTPUT-BASED INSTRUCTION IN FOREIGN LANGUAGE LEARNING
Authors: Erlam Rosemary
Published: December 2003

This paper reErlamviews studies that have contrasted the effectiveness of structured-input instruction with output-based instruction. It then presents results from a study comparing the relative effects of structured-input and output-based instruction on students' ability to comprehend and produce direct object pronouns in second language French. Three classes of students (N = 70) were assigned to three groups: structured-input instruction, output-based instruction, and control. Students were assessed on listening comprehension, reading comprehension, written production, and oral production tasks. All but one of these language measures required a pressured response. Overall, the results showed greater gains for the output-based instruction group.
LANGUAGE, CULTURE, AND TEACHING: CRITICAL PERSPECTIVES FOR A NEW CENTURY.Sonia Nieto. Mahwah, NJ: Erlbaum, 2002. Pp. xvi + 296. $29.95 paper.
Authors: Horváth Enikö
Published: December 2003

This textbook, the second volume in the Language, culture, and teaching series, is a summary of the current issues of multicultural education in schools. As the demography of schools is rapidly changing, Nieto offers skills and tools necessary to face the challenges that these changes bring to current and future teachers regardless of their ethnic background. The book investigates the connection of language and culture, their sociocultural and sociopolitical framework, and the consequences of diversity to school reforms. The introductory chapter gives the reader a general overview of problems related to language, literacy, and culture as they have been seen through historic shifts and arrives at the realization that in education these ideas are inseparable. We need to learn how they influence individual students' learning to teach them successfully.
HISTORICAL LINGUISTICS.Herbert Schendl. Oxford: Oxford University Press, 2001. Pp. xi + 130. $12.95 paper.
Authors: Shapiro Michael C.
Published: December 2003

This brief volume is a contribution to the Oxford introductions to language study series, a set of nontechnical guides to various aspects of the study of language, intended for the general reader with no formal background in linguistics. This book, like the others in the series, is not intended to be a systematic introduction to its subject but rather is designed to give readers a general sense of historical linguistics and to steer them in the direction of further readings. The book is divided into four parts. The first and largest part comprises eight brief essays that treat: (a) the fact that languages evolve over time and attitudes toward them change, (b) data and evidence for reconstructing linguistic history, (c) lexical change, (d) grammatical change, (e) phonological change, (f) language contact, (g) explanations for language change, and (h) recent developments in historical linguistics. The remaining parts of the book contain brief excerpts from readings, further readings, bibliographic references, and a glossary.
LANGUAGE CHANGE AND LANGUAGE CONTACT IN PIDGINS AND CREOLES.John McWhorter (Ed.). Amsterdam: Benjamins, 1999. Pp. vi + 503. $145.00 cloth.
Authors: Corcoran Chris
Published: December 2003

This volume is a selection of 15 papers from approximately 125 papers presented at three consecutive meetings of the Society for Pidgin and Creole Linguistics (San Diego in January 1996, Chicago in January 1997, and London in June 1997). The collection represents a good variety of contributions in terms of theoretical concerns and languages discussed. Two of the chapters present a survey of particular phenomena in a number of pidgins and creoles: stativity and time reference (Holm) and wh-words and question formation (Clements & Mahboob). Another chapter revisits the prototypical creole tense-mood-aspect system with an examination of a larger database of Sranan speech than has been previously seen in the literature (Winford). The remainder of the chapters address historical linguistic concerns, discussing issues of Indo-European development (Goyette) as well as creole genesis. The articles on genesis represent an integration of recent developments from outside the creolist world—for example, using insights from Chaos Theory (Lang) and Optimality Theory (Singler) and expanding on previous discussions of nativization (Roberts). Two chapters represent more quantitative approaches from sociolinguistics applied to creole settings (Naro & Scherre; Tagliamonte). There are four articles that address diachronic issues that would potentially address issues of SLA; however, they do not explicitly address their orientation as to how processes of creole genesis are separate from those of SLA.
WRITING GAMES: MULTICULTURAL CASE STUDIES OF ACADEMIC LITERACY PRACTICES IN HIGHER EDUCATION.Christine Pearson Casanave. Mahwah, NJ: Erlbaum, 2002. Pp. xx + 316. $69.95 cloth, $32.50 paper.
Authors: Khirallah Michael
Published: December 2003

This volume's study of academic literacy practices in higher education is about the writing games we play in the academy. This is not a cynical exploration of such games that assumes the giving up of one's voice to join a discourse community; Casanave's metaphor suggests negotiation in writing games that shapes us, for better or for worse. From Casanave's opening chapter discussing the book's framework to her conclusion, the book is rich in insights about the nature of literacy practices among undergraduate students, Master's students, doctoral students, and faculty.
AN INTRODUCTION TO AMERICAN ENGLISH.Gunnel Tottie. Oxford: Blackwell, 2002. Pp. xx + 294. $68.95 cloth, $31.95 paper.
Authors: Bayley Robert
Published: December 2003

Virtually all American English teachers who have taught outside of the United States have been confronted by student questions about the differences between American and British English, often with the implication that British English is somehow superior. Despite such implications, the economic and political importance of the United States, as well as the attractiveness of American universities to international students, has created a strong demand for more knowledge about American varieties of English. An introduction to American English goes a long way toward meeting that demand.
THE ACQUISITION OF JAPANESE AS A SECOND LANGUAGE.Kazue Kanno (Ed.). Amsterdam: Benjamins, 1999. Pp. xi + 181. $72.00 cloth.
Authors: Izumi Shinichi
Published: December 2003

This volume, focusing on Japanese as a second language (JSL), is part of the Language acquisition and language disorders series by Benjamins. As the editor points out in the introductory chapter, there is a pressing need to investigate the acquisition of languages other than English and other European languages if SLA claims to be a discipline broad enough to encompass acquisition of any second language (L2). In particular, given the importance of Japanese as one of the most commonly studied languages in Asia and the fact that Japanese has many linguistic features not found in European languages, research on the acquisition of JSL should have important implications for both practical applications in language teaching and theoretical investigation of language universals, innate principles, and the like.
STYLISTICS.Peter Verdonk. Oxford: Oxford University Press, 2002. Pp. xiv + 124. $13.50 paper.
Authors: Gross Steven
Published: December 2003

Verdonk has written an engaging and highly accessible introduction to the field of stylistics. The book is organized along the lines of the Oxford introductions to language study series. Like the other volumes in the Oxford series, it contains four sections: a survey of the field, short readings extracted from the literature with study questions that address the issues presented in the survey section, a selection of annotated references, and a glossary of terms.
Inhibitory network properties shaping the light evoked responses of
cat alpha retinal ganglion cells
Authors: O'BRIEN BRENDAN J. , RICHARDSON RANDAL C. , BERSON DAVID M.
Published: December 2003

Cat retinal ganglion cells of the Y (or alpha) type respond to
luminance changes opposite those preferred by their receptive-field
centers with a transient hyperpolarization. Here, we examine the
spatial organization and synaptic basis of this light response by means
of whole-cell current-clamp recordings made in vitro. The
hyperpolarization was largest when stimulus spots approximated the size
of the receptive-field center, and diminished substantially for larger
spots. The hyperpolarization was largely abolished by bath application
of strychnine, a blocker of glycinergic inhibition. Picrotoxin, an
antagonist of ionotropic GABA receptors, greatly reduced the
attenuation of the hyperpolarizing response for large spots. The data
are consistent with a model in which (1) the hyperpolarization reflects
inhibition by glycinergic amacrine cells of bipolar terminals
presynaptic to the alpha cells, and perhaps direct inhibition of the
alpha cell as well; and (2) the attenuation of the hyperpolarization by
large spots reflects surround inhibition of the glycinergic amacrine by
GABAergic amacrine cells. This circuitry may moderate nonlinearities in
the alpha-cell light response and could account for some excitatory and
inhibitory influences on alpha cells known to arise from outside the
classical receptive field.
Temporal modulation sensitivity of tree shrew retinal ganglion
cells
Authors: LU HAIDONG D. , PETRY HEYWOOD M.
Published: December 2003

Tree shrews (Tupaia belangeri) are small diurnal mammals
capable of quick and agile navigation. Electroretinographic and
behavioral studies have indicated that tree shrews possess very good
temporal vision, but the neuronal mechanisms underlying that temporal
vision are not well understood. We used single-unit extracellular
recording techniques to characterize the temporal response properties
of individual retinal ganglion cell axons recorded from the optic
tract. A prominent characteristic of most cells was their sustained or
transient nature in responding to the flashing spot. Temporal
modulation sensitivity functions were obtained using a Gaussian spot
that was temporally modulated at different frequencies (2–60 Hz).
Sustained cells respond linearly to contrast. They showed an average
peak frequency of 6.9 Hz, a high-frequency cutoff at 31.3 Hz, and
low-pass filtering. Transient cells showed nonlinear response to
contrast. They had a peak frequency of 19.3 Hz, a high-frequency cutoff
at about 47.6 Hz, band-pass filtering, and higher overall sensitivity
than sustained cells. The responses of transient cells also showed a
phase advance of about 88 deg whereas the phase advance for sustained
cells was about 43 deg. Comparison with behavioral temporal modulation
sensitivity results suggested that transient retinal ganglion cells may
underlie detection for a wide range of temporal frequencies, with
sustained ganglion cells possibly mediating detection below 4 Hz. These
data suggest that two well-separated temporal channels exist at the
retinal ganglion cell level in the tree shrew retina, with the
transient channel playing a major role in temporal vision.
Two neuropharmacological types of rabbit ON-alpha ganglion cells express GABACreceptors
Authors: ROTOLO THOMAS C. , DACHEUX RAMON F.
Published: December 2003

The major inhibitory neurotransmitters GABA and glycine provide the bulk of input to large-field ganglion cells in the retina. Whole-cell patch-clamp recordings were used to characterize the glycine- and GABA-activated currents for morphologically identified ON-α ganglion cells in the rabbit retina. Cells identified as ON-α cells by light evoked currents were intracellularly stained and examined by light microscopy which revealed dendritic stratification in the vitreal half of the inner plexiform layer and confirmed their physiological identity. All Ca2+-mediated synaptic influences were abolished with Co2+, revealing two types of ON-α cell characterized by their different inhibitory current profiles. One group exhibited larger glycine- than GABA-activated currents, while the other group had larger GABA- than glycine-activated currents. Both cell types demonstrated strychnine-sensitive glycine-activated currents and bicuculline-sensitive GABAA-activated currents. Surprisingly, both cell types expressed functional GABACreceptors demonstrated by their sensitivity to TPMPA. In addition, the cells with larger glycine-activated currents also possessed GABABreceptors, whereas those with larger GABA-activated currents did not. Immunocytochemical experiments confirmed the presence of glycine, GABAA, and GABACreceptor subunits on all physiologically identified ON-α ganglion cells in this study. In addition, the GABABreceptor immunolabeled puncta were present on the cells with larger glycine-activated currents, but not on the cells with the larger GABA-activated currents. In conclusion, the presence of different functional GABA and glycine receptors determined physiologically correlated well with the specific GABA and glycine receptor immunolabeling for two neuropharmacological types of rabbit ON-α ganglion cells.
Connexin 36 in bovine retina: Lack of phosphorylation but evidence for association with phosphorylated proteins
Authors: SITARAMAYYA ARI , CRABB JOHN W. , MATESIC DIANE F. , MARGULIS ALEXANDER , SINGH VINITA , PULUKURI SADHONA , DANG LOAN
Published: December 2003

In vertebrate retina interneuronal communication through gap junctions is involved in light adaptation and in the transfer of visual information from the rod pathway to the cone pathway. Reports over the last two decades have indicated that these gap junctions are regulated by cyclic nucleotide-dependent protein kinases suggesting that the gap junction proteins, connexins, are phosphorylated. Though all the connexins involved in light adaptation and information transfer from rod to cone pathway are not yet known, connexin 36 has been shown to be definitively involved in the latter process. We have therefore attempted to investigate the cyclic nucleotide-dependent phosphorylation of this connexin in bovine retina. We found several soluble and membrane proteins in bovine retina whose phosphorylation was regulated by cyclic nucleotides. However, no protein of about 36 kDa with cyclic nucleotide-regulated phosphorylation was found in gap junction-enriched membrane preparations. A 36-kDa phosphorylated protein was found in gap junction-enriched membranes phosphorylated in the presence of calcium. However, this protein was not immunoprecipitated by anti-connexin 36 antibodies indicating that it was not connexin 36 in spite of its similarity in molecular weight. Immunoprecipitation did reveal phosphorylated proteins coimmunoprecipitated with connexin 36. Two of these proteins were identified as beta and alpha tubulin subunits. Though cyclic GMP and calcium did not greatly influence the association of these proteins with connexin 36, the results suggest the possibility of connexin 36 associating with other proteins. Together, these observations indicate that interneuronal communication at gap junctions made by connexin 36 may not be regulated by direct phosphorylation of connexin 36, but possibly by phosphorylation of associated proteins.
Afferent connectivity to different functional zones of the optic tectum in goldfish
Authors: PÉREZ-PÉREZ M.P. , LUQUE M.A. , HERRERO L. , NÚÑEZ-ABADES P.A. , TORRES B.
Published: December 2003

This work studies the afferent connectivity to different functionally identified tectal zones in goldfish. The sources of afferents contributed to different degrees to the functionally defined zones. The dorsocentral area of the telencephalon was connected mainly with the ipsilateral anteromedial tectal zone. At diencephalic levels, neurons were found in three different regions: preoptic, thalamic, and pretectal. Preoptic structures (suprachiasmatic and preoptic nuclei) projected mainly to the anteromedial tectal zone, whereas thalamic (ventral and dorsal) and pretectal (central, superficial, and posterior commissure) nuclei projected to all divisions of the tectum. In the mesencephalon, the mesencephalic reticular formation, torus longitudinalis, torus semicircularis, and nucleus isthmi were, in the anteroposterior axis, topographically connected with the tectum. In addition, neurons in the contralateral tectum projected to the injected zones in a symmetrical point-to-point correspondence. At rhombencephalic levels, the superior reticular formation was connected to all studied tectal zones, whereas medial and inferior reticular formations were connected with medial and posterior tectal zones. The present results support a different quantitative afferent connectivity to each tectal zone, possibly based on the sensorimotor transformations that the optic tectum carries out to generate orienting responses.
The thermal contribution to photoactivation in A2 visual pigments studied by temperature effects on spectral properties
Authors: ALA-LAURILA PETRI , ALBERT RAULI-JAN , SAARINEN PIA , KOSKELAINEN ARI , DONNER KRISTIAN
Published: December 2003

Effects of temperature on the spectral properties of visual pigments were measured in the physiological range (5–28°C) in photoreceptor cells of bullfrog (Rana catesbeiana) and crucian carp (Carassius carassius). Absorbance spectra recorded by microspectrophotometry (MSP) in single cells and sensitivity spectra recorded by electroretinography (ERG) across the isolated retina were combined to yield accurate composite spectra fromca. 400 nm to 800 nm. The four photoreceptor types selected for study allowed three comparisons illuminating the properties of pigments using the dehydroretinal (A2) chromophore: (1) the two members of an A1/A2 pigment pair with the same opsin (porphyropsinvs.rhodopsin in bullfrog “red” rods); (2) two A2 pigments with similar spectra (porphyropsin rods of bullfrog and crucian carp); and (3) two A2 pigments with different spectra (rodsvs.long-wavelength-sensitive (L-) cones of crucian carp). Qualitatively, the temperature effects on A2 pigments were similar to those described previously for the A1 pigment of toad “red” rods. Warming caused an increase in relative sensitivities at very long wavelengths but additionally a small shift of λmaxtoward shorter wavelengths. The former effect was used for estimating the minimum energy required for photoactivation (Ea) of the pigment. Bullfrog rod opsin with A2 chromophore hadEa= 44.2 ± 0.9 kcal/mol, significantly lower (one-tailedP< 0.05) than the valueEa= 46.5 ± 0.8 kcal/mol for the same opsin coupled to A1. The A2 rod pigment of crucian carp hadEa= 42.3 ± 0.6 kcal/mol, which is significantly higher (one-tailedP< 0.01) than that of the L-cones in the same retina (Ea= 38.3 ± 0.4 kcal/mol), whereas the difference compared with the bullfrog A2 rod pigment is not statistically significant (two-tailedP= 0.13). No strict connection between λmaxandEaappears to exist among A2 pigments any more than among A1 pigments. Still, the A1 → A2 chromophore substitution in bullfrog opsin causes three changes correlated as originally hypothesized by Barlow (1957): a red-shift of λmax, a decrease inEa, and an increase in thermal noise.
The chromatic input to global motion perception
Authors: RUPPERTSBERG ALEXA I. , WUERGER SOPHIE M. , BERTAMINI MARCO
Published: December 2003

For over 30 years there has been a controversy over whether
color-defined motion can be perceived by the human visual system. Some
results suggest that there is no chromatic motion mechanism at all,
whereas others do find evidence for a purely chromatic motion
mechanism. Here we examine the chromatic input to global motion
processing for a range of color directions in the photopic luminance
range. We measure contrast thresholds for global motion identification
and simple detection using sparse random-dot kinematograms. The results
show a discrepancy between the two chromatic axes: whereas it is
possible for observers to perform the global motion task for stimuli
modulated along the red–green axis, we could not assess the
contrast threshold required for stimuli modulated along the
yellowish-violet axis. The contrast required for detection for both
axes, however, are well below the contrasts required for global motion
identification. We conclude that there is a significant red–green
input to global motion processing providing further evidence for the
involvement of the parvocellular pathway. The lack of S-cone input to
global motion processing suggests that the koniocellular pathway
mediates the detection but not the processing of complex motion for our
parameter range.
The gap junction blockers carbenoxolone and 18β-glycyrrhetinic acid antagonize cone-driven light responses in the mouse retina
Authors: XIA YINGQIU , NAWY SCOTT
Published: December 2003

Gap junctions are widely expressed throughout the retina, and play an important role in the processing of visual information. It has been proposed that horizontal cells express unpaired gap junctions, or hemichannels, in their dendrites, and that current flowing through hemichannels reduces transmembrane voltage at cone terminals, promoting the opening of Ca2+channels near sites of transmitter release. This model predicts that pharmacological block of gap junctions should reduce the Ca2+current at the equivalent cone voltage, thereby decreasing the postsynaptic light response. To test this prediction, and estimate the relative magnitude of this effect on third-order cells, we recorded light responses in mouse ganglion cells under photopic conditions and applied two gap junction antagonists, carbenoxolone and the structurally related 18β-glycyrrhetinic acid (GA). Both carbenoxolone and GA decreased the size of the light response to about 30% of control. Cells that were physiologically identified as ON, OFF, or ON/OFF were equally affected by carbenoxolone/GA. These gap junction blockers did not interfere with gamma-aminobutyric acid (GABA) or glutamate receptors, as they did not affect responses to direct activation of these receptors. Under control conditions, spots larger than 200 μm in diameter activated ganglion cell receptive-field surrounds. Comparing responses to small and large spots before and during carbenoxolone treatment, we found that carbenoxolone did not preferentially inhibit surround antagonism at the ganglion cell level, but instead scaled the responses to all spot sizes. Our results extend the findings of studies in lower vertebrates which showed that light responses in horizontal cells are decreased by carbenoxolone treatment, and support the idea that hemichannels in the outer retina, most likely on horizontal cells, constitute important gates that are critical for allowing light responses to move forward into the retinal circuit. Furthermore, it suggests that ganglion cell surrounds are generated in the inner retina.
Light adaptation and color opponency of horizontal cells in the turtle retina
Authors: TWIG GILAD , LEVY HANNA , WEINER ELITE , PERLMAN IDO
Published: December 2003

Chromaticity-type (C-type) horizontal cells of the turtle retina receive antagonistic inputs from cones of different spectral types, and therefore their response to background illumination is expected to reflect light adaptation of the cones and the interactions between their antagonistic inputs. Our goal was to study the behavior of C-type horizontal cells during background illumination and to evaluate the role of wavelength in background adaptation. The photoresponses of C-type horizontal cells were recorded intracellularly in the everted eyecup preparation of the turtleMauremys caspicaduring chromatic background illuminations. The voltage range of operation was either reduced or augmented, depending upon the wavelengths of the background and of the light stimuli, while the sensitivity to light was decreased by any background. The response–intensity curves were shifted to brighter intensities and became steeper as the background lights were made brighter regardless of wavelength. Comparing the effects of cone iso-luminant backgrounds on the Red/Green C-type horizontal cells indicated that background desensitization in these cells could not solely reflect background adaptation of cones but also depend upon response compression/expansion and changes in synaptic transmission. This leads to wavelength dependency of background adaptation in C-type horizontal cells, that is expressed as increased light sensitivity (smaller threshold elevation) and improved suprathreshold contrast detection when the wavelengths of the background and light stimuli were chosen to exert opponent effects on membrane potential.
Immunolocalization of TRPC channel subunits 1 and 4 in the chicken retina
Authors: CROUSILLAC SCOTT , LEROUGE MICHELLE , RANKIN MICHELE , GLEASON EVANNA
Published: December 2003

In the vertebrate retina, multiple cell types express G protein-coupled receptors linked to the IP3signaling pathway. The signaling engendered by activation of this pathway can involve activation of calcium permeable transient receptor potential (TRP) channels. To begin to understand the role of these channels in the retina, we undertake an immunocytochemical localization of two TRP channel subunits. Polyclonal antibodies raised against mammalian TRPC1 and TRPC4 are used to localize the expression of these proteins in sections of the adult chicken retina. Western blot analysis indicates that these antibodies recognize avian TRPC1 and TRPC4. TRPC1 labeling is almost completely confined to the inner plexiform layer (IPL) where it labels a subset of processes that ramify in three broad stripes. Occasionally, cell bodies are labeled. These can be found in the inner nuclear layer (INL) proximal to the IPL, the IPL, and the ganglion cell layer (GCL). Double-labeling experiments using a polyclonal antibody that recognizes brain nitric oxide synthase (bNOS) in the chicken indicate that many of the TRPC1-positive processes and cell bodies also express bNOS. Labeling with the TRPC4 antibody was much more widespread with some degree of labeling found in all layers of the retina. TRPC4 immunoreactivity was found in the photoreceptor layer, in the outer plexiform layer (OPL), in radially oriented cells in the INL, diffusely in the IPL, and in vertically oriented elements below the GCL. Double-labeling experiments with a monoclonal antibody raised against vimentin indicate that the TRPC4-positive structures in the INL and below the GCL are Müller cells. Thus, TRPC1 and TRPC4 subunits have unique expression patterns in the adult chicken retina. The distributions of these two subunits indicate that different retinal cell types express TRP channels containing different subunits.
Body size plasticity and local variation of relative head and body size sexual dimorphism in garter snakes (Thamnophis sirtalis)
Authors: Krause Mark A. , Burghardt Gordon M. , Gillingham James C.
Published: December 2003

For snakes, prey size and sex are two possible determinants of head and body size. In garter snakes Thamnophis sirtalis, females are generally longer and have greater body weights than males, and also have larger relative head sizes, which may facilitate foraging success. The selective pressures that account for sexual size dimorphism in garter snakes have not been unequivocally demonstrated. In this study, the body (length and mass) and head (head length, head width, jaw length, inter‐ocular distance) sizes of garter snakes inhabiting two nearby but ecologically dissimilar sites with different types of available prey were compared. Overall, the adult female snakes were larger and had greater relative head sizes than males. Males from the two sites did not differ significantly in body or head sizes. However, the mean body length and mass of females from a site where vertebrates are included in the diet were greater than that of females feeding almost exclusively on earthworms. There were also significant site differences in all four head measurements in females, although the direction of the difference varied by site. Diet‐induced morphological plasticity is well documented and was evident in this study, although the relative roles of genotype, ontogeny, and competing selective forces in the expression of such plasticity can only be ascertained through future experimental studies.
Editorial: Experiments of nature: Contributions to developmental theory
Authors: CICCHETTI DANTE
Published: December 2003

One of the distinguishing principles that has guided research conducted within a developmental psychopathology perspective is that knowledge of normal development is necessary to comprehend psychopathology and that, conversely, the examination of maladaptive and psychopathological development can elucidate the normal functioning of individuals (Cicchetti, 1984, 1990a, 1990b, 1993; Rutter, 1986; Sroufe, 1990; Werner, 1948). Because all pathology can be conceived as a disturbance, distortion, or degeneration of normal functioning, in order to understand psychopathology it is essential that the normal functioning with which psychopathology is compared be fully grasped (Cicchetti, 1984, 1990a; Kaplan, 1967; Rutter & Garmezy, 1983). Likewise, understanding how mental disorders evolve and how aberrations in the organization of component developmental systems that exist among disturbed individuals eventuate may be informative for elucidating critical components of normal development.
Natural experiments to study the effects of early experience: Progress and limitations
Authors: O'CONNOR THOMAS G.
Published: December 2003

Questions concerning the long-term effects of early experience on psychological development in humans continue to stir up controversy. There are, at present, great diversity and contradictions among extant conceptual models and inadequate data to resolve these differences. Limited opportunities to use experimental approaches and the inherent restrictions of observational approaches in research on humans implies that alternative research designs are needed. This article examines the use of “natural experiments” as a method for testing hypotheses concerning the effects of early experience on psychological development. The benefits and limitations of using natural experiments are reviewed and several case illustrations are considered.
The impact of institutionalization on child development
Authors: MACLEAN KIM
Published: December 2003

During the past 10 years researchers studying children adopted from Romanian orphanages have had the opportunity to revisit developmental questions regarding the impact of early deprivation on child development. In the present paper the effects of deprivation are examined by reviewing both the early and more recent literature on studies of children who spent the first few years of life in institutions. Special attention is given to the Canadian study of Romanian adoptees in which the author has been involved. Findings across time and studies are consistent in showing the negative impact of institutionalization on all aspects of children's development (intellectual, physical, behavioral, and social–emotional). Results of studies show, however, that institutionalization, although a risk factor for less optimal development, does not doom a child to psychopathology. However, the impact of institutionalization is greater when coupled with risk factors in the postinstitutional environment. Methodological and conceptual difficulties in research with institutionalized samples of children are discussed and future directions for research are considered.
Adoption as a natural experiment
Authors: HAUGAARD JEFFREY J. , HAZAN CINDY
Published: December 2003

Adoption provides a unique opportunity for the study of child development. Because adopted children are raised in families in which they have no genetic relationship with their parents, and possibly none with their siblings, they provide a rare opportunity to study the relative importance of genetic, shared environmental, and nonshared environmental influences on the development of child characteristics and behaviors. Because children are adopted from a variety of circumstances and at a wide range of ages, studies of adopted children and their families provide researchers the opportunity to examine the short- and long-term influences of a wide range of environments on children's development. Because children are adopted into homes with a range of characteristics (e.g., multiracial homes), adoption provides the opportunity to study the range of influences of these homes on child development. Adoption research that focuses on each of these areas is reviewed in this article. We present conclusions about the value of adoption in psychological research and some reasons why many psychologists ignore the opportunities presented by studying adoptive families, as well as potential useful directions for future research with adopted children and their families.
Temperament and coping: Advantages of an individual differences perspective
Authors: DERRYBERRY DOUGLAS , REED MARJORIE A. , PILKENTON–TAYLOR CAROLYN
Published: December 2003

This paper examines the advantages that arise from an individual differences approach to children's coping and vulnerabilities. It suggests that the basic motivational and attentional systems involved in temperament constitute relatively primitive coping mechanisms. With development, these primitive coping skills are aided by representational and other cortical functions, allowing the coping process to begin before a stressful event and thereby increasing the child's capacity to plan an effective coping option and to enhance self-control. Such an emphasis on motivational and attentional differences allows us to take advantage of children's diverse personalities as “experiments of nature” and to better understand the temperamental patterns that contribute to adaptive and maladaptive outcomes.
False belief understanding in maltreated children
Authors: CICCHETTI DANTE , ROGOSCH FRED A. , MAUGHAN ANGELINE , TOTH SHEREE L. , BRUCE JACQUELINE
Published: December 2003

False belief understanding was investigated in maltreated (N = 203), low socioeconomic status (SES) nonmaltreated (N = 143), and middle SES nonmaltreated (N = 172) 3- to 8-year-old children. Contrasts among the three groups provided an opportunity to examine the impact of family contextual influences on theory of mind development. Specifically, child maltreatment served as an “experiment of nature” in order to elucidate theory of mind abilities. Two false belief tasks and language assessments were administered. Among children with a verbal mental age of 49 months or greater, maltreatment was related to delays in the development of theory of mind, beyond the influence of chronological age and SES. The occurrence of maltreatment during the toddler period, onset during the toddler years, and physical abuse were features of maltreatment associated with delay in the development of theory of mind. Findings are discussed in terms of the influence of harsh caregiving on the development of theory of mind. Implications for the understanding of normal developmental processes are highlighted.
Designing research to study the effects of institutionalization on brain and behavioral development: The Bucharest Early Intervention Project
Authors: ZEANAH CHARLES H. , NELSON CHARLES A. , FOX NATHAN A. , SMYKE ANNA T. , MARSHALL PETER , PARKER SUSAN W. , KOGA SEBASTIAN
Published: December 2003

This paper provides an overview of the largest longitudinal investigation of institutionalized children less than 2 years old ever conducted. The Bucharest Early Intervention Project is an ongoing randomized controlled trial of foster placement as an alternative to institutionalization in abandoned infants and toddlers being conducted in Bucharest, Romania. In addition to describing the contexts in which this study is imbedded, we also provide an overview of the sample, the measures, and the intervention. We hope that the natural experiment of institutionalization will allow us to examine directly the effects of intervention on early deprivation. We hope it will provide answers to many of the critical questions that developmentalists have asked about the effects of early experience, the timing of deprivation, and the ameliorating effects of early intervention and provide clues to which underlying neurobiological processes are compromised by, and resilient to, dramatic changes in early experience.
The behavioral neurogenetics of fragile X syndrome: Analyzing gene–brain–behavior relationships in child developmental psychopathologies
Authors: REISS ALLAN L. , DANT CHRISTOPHER C.
Published: December 2003

Analyzing gene–brain–behavior linkages in childhood neurodevelopmental disorders, a research approach called “behavioral neurogenetics,” has provided new insights into understanding how both genetic and environmental factors contribute to complex variations in typical and atypical human development. Research into etiologically more homogeneous disorders, such as fragile X syndrome, in particular, allows the use of more precise metrics of genetic risk so that we can more fully understand the complex pathophysiology of childhood onset neurodevelopmental disorders. In this paper, we review our laboratory's behavioral neurogenetics research by examining gene–brain–behavior relationships in fragile X syndrome, a single-gene disorder that has become a well-characterized model for studying neurodevelopmental dysfunction in childhood. Specifically, we examine genetic influences, trajectories of cognition and behavior, variation in brain structure and function, and biological and environmental factors that influence developmental and cognitive outcomes of children with fragile X. The converging approaches across these multilevel scientific domains indicate that fragile X, which arises from disruption of a single gene leading to the loss of a specific protein, is associated with a cascade of aberrations in neurodevelopment, resulting in a central nervous system that is suboptimal with respect to structure and function. In turn, structural and functional brain alterations lead to early disruption in emotion, cognition, and behavior in the child with fragile X. The combination of molecular genetics, neuroimaging, and behavioral research have advanced our understanding of the linkages between genetic variables, neurobiological measures, IQ, and behavior. Our research and that of others demonstrates that neurobehavior and neurocognition, genetics, and neuroanatomy are all different views of the same intriguing biological puzzle, a puzzle that today is rapidly emerging into a more complete picture of the intricate linkages among gene, brain, and behavior in developing children. Understanding the complex multilevel scientific perspective involved in fragile X will also contribute to our understanding of normal development by highlighting developmental events throughout the life span, thereby helping us to delineate the boundaries of pathology.
What can developmental disorders tell us about the neurocomputational constraints that shape development? The case of Williams syndrome
Authors: KARMILOFF–SMITH ANNETTE , THOMAS MICHAEL
Published: December 2003

The uneven cognitive phenotype in the adult outcome of Williams syndrome has led some researchers to make strong claims about the modularity of the brain and the purported genetically determined, innate specification of cognitive modules. Such arguments have particularly been marshaled with respect to language. We challenge this direct generalization from adult phenotypic outcomes to genetic specification and consider instead how genetic disorders provide clues to the constraints on plasticity that shape the outcome of development. We specifically examine behavioral studies, brain imaging, and computational modeling of language in Williams syndrome but contend that our theoretical arguments apply equally to other cognitive domains and other developmental disorders. While acknowledging that selective deficits in normal adult patients might justify claims about cognitive modularity, we question whether similar, seemingly selective deficits found in genetic disorders can be used to argue that such cognitive modules are prespecified in infant brains. Cognitive modules are, in our view, the outcome of development, not its starting point. We note that most work on genetic disorders ignores one vital factor, the actual process of ontogenetic development, and argue that it is vital to view genetic disorders as proceeding under different neurocomputational constraints, not as demonstrations of static modularity.
The effect of adverse intrauterine and newborn environments on cognitive development: The experiences of premature delivery and diabetes during pregnancy
Authors: SESMA HEATHER WHITNEY , GEORGIEFF MICHAEL K.
Published: December 2003

The prenatal and early postnatal periods constitute a time of rapid development when the brain is in a state of both heightened plasticity and vulnerability. Premature infants and infants of diabetic mothers represent two experiments of nature that allow researchers to observe how the developing brain responds to early biological challenge of either a global or regionally specific nature. We outline a set of organizing principles for conceptualizing the mechanisms by which early adverse experience may be encoded in the brain and subsequently expressed in behavior. We then review the available literature on developmental outcomes for infants born premature and infants of diabetic mothers. Research examining the relative influence of experience and maturation in the development of preterm infants indicates that advance experience does not accelerate the advent of specific cognitive capacities, but may enhance performance once the particular ability has emerged. Long-term follow-up of preterm infants also reveals evidence for plasticity and cognitive improvement into early adolescence for later maturing executive functions. Finally we offer an integrated model for investigating cognitive outcomes in infants of diabetic mothers that incorporates data from animal, electrophysiological, and behavioral measures.
Cognitive development in children born preterm: Implications for theories of brain plasticity following early injury
Authors: LUCIANA MONICA
Published: December 2003

The human brain is functionally altered through experience, a phenomenon known as plasticity. Relevant experiences may be negative, as in brain injury. Adult brain injury results in permanent impairment. However, it has been assumed that early injury leads to substantial functional recovery. Animal studies suggest several predictions regarding whether this principle generally holds true. These studies indicate that the timing of brain injury, relative to the expected course of neurodevelopment, impacts the extent of recovery. Injuries occurring during the period of cell migration are particularly detrimental. However, outcome must be assessed longitudinally because apparent recovery in childhood may reverse as the brain matures. Moreover, recovery of one function may come at the expense of others. Whether these findings characterize outcome following preterm birth is the focus of this review. Preterm birth is associated with high rates of neurodevelopmental disability, primarily due to hypoxic–ischemic events. Periventricular brain structures and white matter tracts are particularly vulnerable to damage. Through school age, preterm children exhibit diminished levels of global intellectual function, attention, memory, and reasoning skills relative to full-term peers. It is questionable whether these deficits persist. Because few studies have followed recent cohorts into young adulthood, it is argued that outcome cannot be reliably described based on the available literature. Moreover, important contributors to later development have been neglected, including both genetic and experiential factors. With improved assessment, it may be possible to develop interventions based on the individual child's constellation of genetic, biological, and sociodemographic risks.
An approach to the psychobiology of personality disorders
Authors: POSNER MICHAEL I. , ROTHBART MARY K. , VIZUETA NATHALIE , THOMAS KATHLEEN M. , LEVY KENNETH N. , FOSSELLA JOHN , SILBERSWEIG DAVID , STERN EMILY , CLARKIN JOHN , KERNBERG OTTO
Published: December 2003

Human variability in temperament allows a unique natural experiment where reactivity, self-regulation, and experience combine in complex ways to produce an individual personality. Personality disorders may result from changes in the way past memories filter new information in situations of emotional involvement with others. According to this view, disorders are specific to their initiating circumstances rather than a general difficulty that might extend to classes of information processing remote from triggers for the disorder. A different view suggests a more general deficit in attentional control mechanisms that might extend to a wide range of situations far from those related to the core abnormality. This paper outlines methods for examining these views and presents data from the study of borderline personality disorder, arguing in favor of high negative emotionality being combined with a deficit in an executive attentional control network. Because this attentional network has already been well described in terms of anatomy, the cognitive operations involved, development, chemical modulators, and effects of lesions and candidate genes, these findings may have implications for understanding the disorder and its treatment. We consider these implications in terms of a general approach to the study of personality development and its disorders.
A Partition Theorem for Scattered Order Types
Authors: Komjáth Péter , Shelah Saharon
Published: December 2003

If φ is a scattered order type, and μ is a cardinal, then there exists a scattered order type ψ such that holds.
A Note on Explicit Ramsey Graphs and Modular Sieves
Authors: Grolmusz Vince
Published: December 2003

In a previous paper we found a relation between the ranks of co-diagonal matrices (matrices with zeroes in their diagonal and nonzeroes elsewhere) and the quality of explicit Ramsey graph constructions. We also gave a construction based on the BBR polynomial of Barrington, Beigel and Rudich. In the present work we give another construction for low-rank co-diagonal matrices, based on a modular sieve formula.