Research in Developmental Disabilities 37 (2015) 216–222

Contents lists available at ScienceDirect

Research in Developmental Disabilities

When words lead to solutions: Executive function deficits

in preschool children with specific language impairment

Mara Roello a, Maria Letizia Ferretti a, Valentina Colonnello b, Gabriel Levi a,*a Department of Child Neuropsychiatry, Sapienza University of Rome, Via dei Sabelli 108, 00185 Rome, Italyb Department of Psychology, Laboratory for Biological and Personality Psychology, University of Freiburg, D-79104 Freiburg i. Br., Germany

A R T I C L E I N F O

Article history:

Received 5 August 2014

Received in revised form 20 November 2014

Accepted 25 November 2014

Available online 18 December 2014

Keywords:

Preschool

Language

Problem solving

Action

A B S T R A C T

Several studies indicate that school-age children with specific language impairment (SLI)

have difficulties with tasks that rely on executive functions. Whether executive function

deficits in children with SLI emerge during preschool age remains unclear. Our aim was to

fill this gap by investigating executive function performances in two age groups of

preschoolers with and without SLI. Children with SLI (N = 60; young: 53.6 � 5.3 months;

old: 65.4 � 3.8 months) and age-matched control children (N = 58) were tested for problem-

representation ability, using the Flexible Item Selection Task (FIST), rule-use skills, using a

Stroop-like Day–Night test (D/N), and planning skills, using the Tower of London test (TOL).

Older children performed better than younger children did across tasks. Children with SLI had

poorer performance, compared to typically developing children, on measures of problem

representation, planning skills, and use of rules. Our results clearly indicate that executive

function impairment is evident during the preschool period. Although old children with SLI

performed better than young children with SLI, their performances were still poor, compared

to those of control peers. These findings suggest that children with SLI have altered executive

functioning at 53.6 months.

� 2014 Published by Elsevier Ltd.

1. Introduction

During a child’s early development, motor, language acquisition and executive functioning abilities are clearlyinterdependent. For example, the age of verb acquisition and proficiency in using the body to perform the correspondingaction are correlated (Maouene, Hidaka, & Smith, 2008), and early simultaneous use of speech and hand movements may bea predictor of later language development (Iverson & Goldin-Meadow, 2005). Furthermore, children are able to bodilyproduce actions related to verbs before they are able to verbally produce the linguistic labels associated to them (Levi,Colonnello, Giacche, Piredda, & Sogos, 2014). The progressive mastering of bodily actions plays a key role for the earlylanguage acquisition and cognitive processes (Merleau-Ponty, 1945/1962; Piaget & Inhelder, 1966/1969; Clark, 1997;Iverson, 2010). In childhood, the language becomes a mean for expression of actions, for reflection of one’s own performedactions, and planning of future potential ones. The externally directed language is progressively internalized and used to self-direct one’s own external behavior to solve problems (Marcovitch & Zelazo, 2009).

* Corresponding author. Tel.: +39 644712203; fax: +39 64957857.

E-mail addresses: mara.roello@libero.it (M. Roello), marialetizia.ferretti@uniroma1.it (M.L. Ferretti), valentina.colonnello@psychologie.uni-freiburg.de

(V. Colonnello), gabriel.levi@uniroma1.it (G. Levi).

http://dx.doi.org/10.1016/j.ridd.2014.11.017

0891-4222/� 2014 Published by Elsevier Ltd.

M. Roello et al. / Research in Developmental Disabilities 37 (2015) 216–222 217

In this view, the study of language development and related disorders may not considered independently from otherabilities and cognitive processes. Thus, the aim of the present study is to further the understanding of relations betweenlanguage and executive functioning development during problem solving tasks in children with language disorder.

Specific language impairment (SLI) is a common developmental disorder that primarily impairs language and speechabilities and is not related to/or caused by other developmental disorders, such as hearing loss or acquired brain injury(Leonard, 1998). Although this disorder is designated as ‘‘specific’’ because of the absence of impairment in others aspects ofintellectual development, deficits are not entirely restricted to the language domain. For example, several studies havedemonstrated that school-age children with SLI have poor performances on measures of fine and gross motor abilities (Finlay& McPhillips, 2013; Iverson & Braddock, 2011; Zelaznik & Goffman, 2010; Hill, Bishop, & Nimmo-Smith, 1998) andprocedural memory (Lum, Conti-Ramsden, Page, & Ullman, 2012). In addition, children with language disorders showimpairment in imitation skills, kinesthetic awareness (Marton, 2009), and processing of simultaneous information (Marton& Schwartz, 2003; Marton, Schwartz, Farkas, & Katsnelson, 2006). Recent studies indicate that school-age children withlanguage impairment perform poorly compared to typically developing peers on measures of mental attention, interruption,and updating (Im-Bolter, Johnson, & Pascual-Leone, 2006). Furthermore, as Bishop and Norbury (2005a,b) havedemonstrated, children with communication impairments are more likely to have difficulties during inhibition tasks.Children with SLI also generally show poor performance in concept generation, cognitive flexibility, visual–spatial planning,and in visual–spatial tasks with high executive function demands (Marton, 2008), all of which have obvious detrimentaleffects on the learning process.

The relations between SLI and executive functions have mainly been investigated in school-age children. However, giventhe importance of detecting manifestations of difficulties in early development and given the strong relation between bodilyactions, language and reasoning, the question arises whether preschool-age children with SLI show poor executivefunctioning in problem solving tasks. Although language and inner speech acquisition play crucial roles in the developmentof executive functions and problem solving (Fernyhough & Fradley, 2005; Vygotsky, 1987), relatively little is known aboutpossible impairments of executive functions in preschool children with SLI.

According to classic neuropsychological theories and recent experimental studies, children’s ability to plan, monitor, andregulate their own behavior increases between the ages of four and seven, along with the development of self-directedspeech (Fernyhough & Fradley, 2005; Alarcon-Rubio, Sanchez-Medina, & Prieto-Garcıa, 2014; Luria, 1961; Luria & Yudovich,1971). However, changes in several aspects of executive functions occur in the preschool period (Hongwanishkul, Happaney,Lee, & Zelazo, 2005; Jacques, Zelazo, Kirkham, & Tanya, 1999; Jacques & Zelazo, 2001). Specifically, children with typicaldevelopment progressively acquire representational flexibility (i.e., the ability to manipulate representations) and responsecontrol to follow rules (Zelazo, Reznick, & Spinazzola, 1998; Jacques & Zelazo, 2001). These abilities are consideredfundamental for several problem solving tasks, such as the classification of items (Piaget & Inhelder, 1966/1969), imitation,and perspective taking tasks (Simcock & DeLoache, 2006).

In this framework, we hypothesized that alterations of executive function development in children with SLI also emergeduring the preschool period. Because problem solving is considered to be the main outcome of executive functions (Zelazo &Frye, 1997; Zelazo & Muller, 2002), we examined whether children with a diagnosis of SLI have more difficulties than do theirtypically developing peers regarding problem representation, planning, and execution of plans. To better analyze earlymanifestations of executive function difficulties and to shed light on the developmental course such deficits in children withSLI, we contrasted the performances of two age groups.

We predicted that children with SLI would perform worse than children with typical development on all the tasks. Inaddition, we predicted that both young and old children with SLI would perform worse than control children on all the tasks.

2. Methods

2.1. Participants

All children came from Italian-speaking families and were monolingual. Children in the study were placed into alanguage group, SLI or control. The SLI group consisted of 60 children, while the control group consisted of 58 children withtypical development. Within each language group, children were divided into two age groups: young children (SLI-young:24 boys, 6 girls, age: M = 53.6 months, SD = 5.3; Control-young: 11 boys, 18 girls, age: M = 53.4 months; SD = 2.7) and oldchildren (SLI-old: 25 boys, 5 girls, age: M = 65.4 months, SD = 3.8; Control-old: 11 boys, 18 girls, age: M = 66.1 months,SD = 3.4).

Children with SLI were referred to the Division of Child Neuropsychiatry of University of Rome ‘‘Sapienza,’’ because oflanguage delay. They were included in the study after diagnosis by a specialized interdisciplinary group composed of a childpsychiatrist, a developmental rehabilitation therapist, and a psychologist.

Assessment of SLI included administration of the Rustioni test of language comprehension (Rustioni, 1994), the Peabodyreceptive communication test (Peabody Picture Vocabulary Test III, Dunn & Dunn, 1997), and the Italian translations of theWechsler Intelligence Scale for Children-Revised (WISC-R; Rubini & Padovani, 1986, Table 1). Among the inclusion criteriafor the group with SLI were impaired vocabulary comprehension and morphosyntactic production (Cipriani et al., 1993).Exclusion criteria were rehabilitation center enrollment, a history of socio-economic deprivation, IQ < 85, and hearingdeficits.

Table 1

Rustioni, Peabody, and WISC-R scale – TIQ = total score, VIQ = verbal; score, PIQ = performance

score in the young and old age groups of children with SLI.

Test Young Mean (SD) Old Mean (SD)

Rustioni 70 (16.7) 70 (21.8)

Peabody 80 (12.2) 79.8 (9.8)

WISC-R

TIQ 103.7 (9.7) 101.6 (13.8)

VIQ 96.8 (11.8) 96.9 (14.6)

PIQ 111.6 (11.6) 110.2 (21.9)

M. Roello et al. / Research in Developmental Disabilities 37 (2015) 216–222218

Control children were recruited from kindergartens. According to parents’ reports, each had no a history of socio-economic deprivation, no hearing loss, and had typical language, motor, cognitive, and socio-emotional development.

2.2. Procedure

All children completed the following tests.Flexible Item Selection Task (FIST, Jacques & Zelazo, 2001): This test measures categorization and shifting abilities.

According to the problem-solving framework model (Zelazo & Frye, 1997), the FIST measures problem-representation phaseabilities. Children were shown a set of three pictures and were asked to select two pictures that matched each other in onefeature (categorization session); they were then asked to choose a different pair of pictures matching in a different feature(shifting session). Each child received a categorization score (0–30) and a shifting score (0–15). This task uses inductivereasoning and cognitive flexibility abilities as, in each set of pictures, one of the pictures has to be selected twice, butaccording to different features.

Stroop-like Day–Night test (D/N; Gerstadt, Hong, & Diamond, 1994): The D/N assesses execution-phase (understanding/following rules/action control) abilities, as it requires inhibitory control of actions in conjunction with learning and recallingrules. In this test, children were shown a set of cards, some black, with a moon and stars, and some white, with a bright sun.They were then instructed to say ‘‘day’’ when shown a black card and to say ‘‘night’’ when shown a white card. Each childreceived a total score (0–16) based on the number of correct actions per trial.

Tower of London test (TOL; Krikorian, Bartok, & Gay, 1994): This test measures planning-phase abilities. Thechildren were presented with colored, perforated balls (green, red, and blue), which they were to place on three pegs ofgraduated sizes, vertically attached to a wooden board. The test consisted of a series of problems of increasing difficultyin which children were required to move the balls from an initial state to a target state that matched the arrangementshown in a picture presented by the experimenter. Specific rules also had to be followed: (i) move only one ball at atime; (ii) move the ball from one peg to another, without placing the ball on the table or holding more than one ball; (iii)place one ball on the shortest peg, two on the medium peg, and three on the tallest peg; and (iv) use only the number ofmovements established by the experimenter. Thus, to solve the problem in this task, children had to not only mentallyrepresent the problem and inhibit their actions but also plan out several actions in advance. Each child received a scoreranging from 0 to 36.

Individual testing took place in a quiet room. All children were tested by the same experimenter. The test order wasrandomized across age and language groups, and to minimize possible effects of tiredness and learning, the three tasks werepresented at 15-min intervals. Neither positive nor negative feedback was provided during the testing.

The protocol was approved by the University of Rome Sapienza review board and all parents signed a consent form.

2.3. Statistical analysis

For each task, performance was analyzed using analysis of variance (ANOVA), with group (SLI vs. control) and age group(young group vs. old group) treated as between-subjects factors. For significant interaction effects, a post hoc analysis wasperformed.

3. Results

3.1. FIST test

For the categorization session, the analysis revealed a main effect of group, F(1,114) = 4, p = .048, h2p ¼ :04, indicating that

children with SLI categorized fewer cards compared to control children. A main effect of age was found, F(1,114) = 19.6,p < .001, h2

p ¼ :14, with younger children categorizing fewer cards than older children. The group � age interaction was notsignificant, F(1,114) = 2.2, p = .14, Fig. 1a.

On the shifting session, the analysis revealed a main effect of group, F(1,114) = 4, p = .046. h2p ¼ :04. Children with SLI

scored significantly lower than control children. A main effect of age was found, F(1,114) = 25, p < .001, h2p ¼ :17, with

Fig. 1. Mean � SE of (a) scores on the FIST categorization (b) FIST shifting (c) D/N test; and (d) TOL test in young and old groups of control children and children

with SLI *p < 0.05 after post hoc comparison.

M. Roello et al. / Research in Developmental Disabilities 37 (2015) 216–222 219

M. Roello et al. / Research in Developmental Disabilities 37 (2015) 216–222220

younger children scoring lower than older children. No interaction effects between group and age groups found,F(1,114) = 1.5, p = .2, Fig. 1b.

3.2. D/N test

Four young children with SLI refused to complete the test; their data was excluded. Analysis of the remaining datarevealed a significant main effect of group, F(1,110) = 16, p = .001, h2

p ¼ :1, with control children scoring higher than childrenwith SLI. A main effect of age was found, F(1,110) = 4.5, p = .03, h2

p ¼ :04, with old children scoring higher than youngchildren. The interaction between group and age was not significant, F(1,110) = 2, p = .1, Fig. 1c.

3.3. TOL test

The data from five young and two old children with SLI were excluded because the children refused to complete the test.Analysis of the remaining data revealed a main effect of group, F(1,107) = 8.5, p = .004, h2

p ¼ :07, indicating that children withSLI scored significantly lower than did the control children. There was a significant main effect of age, F(1,107) = 47.7,p < .001, h2

p ¼ :3, with younger children scoring lower than older children. The post hoc analysis on the significantgroup � age interaction, F(1,107 ) = 8.3, p = .005, h2

p ¼ :07, revealed that the difference was mainly due to the low scores ofthe older children with SLI, Fig. 1d].

4. Discussion

Problem solving implies recruitment of several executive function abilities, including creating a mental representation ofthe problem, planning one’s actions, and executing and evaluating those actions (Zelazo & Muller, 2002). In our study,children with SLI clearly showed less ability for problem representation and less cognitive flexibility compared to theirtypically developing peers, as indicated by their low scores on categorization and shifting tasks. Furthermore, children withSLI were less able to inhibit actions, recall rules, and elaborate plans of action. Specifically, difficulties in abstract reasoningand action control were already evident at 53.6 months: The young group of children with SLI scored lower than theirage-matched peers did on the FIST and D/N. Although abilities in categorization, cognitive flexibility, and application ofrules improved with age in both groups of children, the performance of the children with SLI remained lower overall.Furthermore, children with SLI had more difficulties with planning at 65.4 months on the TOL task, presumably due tolimited acquisition of language abilities needed to solve complex task.

Taken together, our results are in line with classic theories and experimental evidence that link language and reasoningdevelopment (Fuhs & Day, 2011; Bowerman & Levinson, 2001; Vygotsky, 1987). In addition, they corroborate previousresults indicating that children with SLI show impairments in executive functioning (Henry, Messer, & Nash, 2012) andextend previous work demonstrating that executive function impairments in SLI emerge during the preschool age. Our studyalso reveals that problem-solving performance improves with age in both groups, which suggests typical, but delayed,executive functioning development in children with SLI.

Problem-solving performance has been shown to be positively associated with self-directed speech usage in typicallydeveloping children (Alarcon-Rubio et al., 2014; Fernyhough & Fradley, 2005). Specifically, children with typicaldevelopment may use the language for ‘reflective consciousness’ and regulation of one’s own behavior on goal-directedproblem-solving tasks (Zelazo, 2004). Thus, it is possible that difficulty to use the language may be at the basis ofthe reduced ability to elaborate a general rule of solution (i.e., ‘‘say the opposite’’) and to inhibit the expression of aword semantically related to the required word in the D/N task, as well as to plan actions in the TOL task. Futurestudies should specifically investigate the interplay between motor and semantic problems on problem solving taskin children with SLI.

Although the present study added to the understanding of the executive function difficulties in children with SLI, twolimitations should be considered. First, we cannot exclude the possibility that the unequal distribution of males and femalesper group might have affected the results. In addition, given the lack of information of demographic and IQ scores in thecontrol group, a direct contrast between children with SLI and control children with respect to these factors was not possible.Thus, future studies aimed at replicating the present findings on a larger sample should take into account these factors.

Given the relation between development of motor, language and reasoning development, future studies should furtherinvestigate whether the antecedents of executive function difficulties in children with SLI may be traced back to early deficitsin creating mental representations of actions. As child development theories, embodied cognition theories, and severalexperimental studies suggest, the development of language and motor abilities are strongly interconnected (Levi,Colonnello, Giacche, Piredda, & Sogos, 2013; Glenberg & Gallese, 2012; Iverson & Braddock, 2011; Fischer & Zwaan, 2008;Piaget & Inhelder, 1966/1969). For example, at 2 years, typically developing children are able to perform specific actionswhen asked, even if they are unable to verbally produce the words representing those actions (Levi et al., 2013); however, at3 years, children with SLI enact—express through the body—fewer action-related words than do typically developingchildren (Levi et al., 2014). In addition, children with SLI are less able to perform several motor-related tasks than are theirtypically developing peers (Iverson & Braddock, 2011; Hill et al., 1998). Thus, future longitudinal studies should trace thedevelopment of SLI manifestation by investigating whether early difficulty to enact single action-related words (i.e., verbs) at

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2 years predicts later problems to enact a sequence of actions, and thus the emergence of executive function impairment,during the 4th year.

Of note, TOL requires a sequence of actions, that is, the transformation of a current status into a potential, future status.Thus, future studies should also extend previous studies on temporal processing in school-age children (Grondin et al., 2007)and investigate whether, in preschool children with SLI, deficits in planning abilities are associated with altered temporalprocessing of the before–after relationship. Indeed, executive functions are future-oriented behaviors: Elaborating plansrelies on the ability to represent a sequence, a temporal organization of actions (McCormack & Hanley, 2011; Benson, 1997).Furthermore, planning implies the ability to represent the present status while mentally modeling possible sequences ofactions for reaching a future goal. Given that time processing recruits some of the subcortical and cortical neural networksinvolved in motor coordination and language processing (Schubotz et al., 2000; Macar et al., 2002), the relation betweenmotor development, language acquisition, timing ability, and abstract reasoning in children with SLI deserves furtherinvestigation.

In sum, our results provide evidence that preschool children with SLI show alterations of executive functioning in allphases of problem solving. Difficulties with inhibiting interfering verbal responses could be due to a difficulty in using innerspeech to mentally represent rules and inhibit behavior. Our findings lend support to classic theories on child developmentand point to possible difficulties in using language as a tool for reasoning as early as preschool age in children with SLI.

Acknowledgments

We are very grateful to Dr. Sophie Jacques (Dalhousie University) for sharing the FIST test and for her insightful commentsand suggestions during the initial stages of the work. We sincerely thank the anonymous reviewer for the constructivecomments and all children and parents who participated in the study. The study was supported by a Regione Lazio grant toG.L.

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