Psychology researchers and educators have determined that many behavioral and cognitive abilities that we want to

understand, measure, and manipulate are related to the function of working memory. Working memory, a cognitive system with

limited capacity, temporarily stores and processes information relevant to ongoing activity (Baddeley, 2000). Unlike shortterm

memory, working memory has a longer developmental period and is affected by the maturation of the brain’s frontal lobes

(Cowan, 1997). This cognitive ability is essential not only for children’s interactions with the external world and acquisition of

new knowledge but also for their daily functioning.

Although different theories provide various explanations for the development of working memory, most theories hold that

working memory involves two cognitive operations: storage and processing (Baddeley, 2000; Engle & Kane, 2004; Gavens &

Barrouillet, 2004). Therefore, tasks that measure a person’s working memory span typically require the person to temporarily

remember a memory item while performing another processing task or to engage in some form of processing related to the

memory item. They are specifically called dual-task or complex span tasks (Redick et al., 2012). Such tasks differ from simple

span tasks, which require the testee to retain memory items for a period of time and then recall them sequentially.

Assessing children’s working memory by using complex span tasks requires clear, simple, and easy-to-understand

instructions. The tasks must be designed with stimuli, content, presentation formats, and response methods that are consistent

with children’s cognitive abilities. In addition, test procedures should account for children with varying levels of working

memory capacity. For those with low working memory capacity, the tasks should avoid inducing a sense of frustration or

helplessness. By contrast, for children with high working memory capacity, the test should provide opportunities for them to

fully demonstrate their abilities. A common approach involves gradually increasing the difficulty of the tasks, requiring the

testee to memorize more items, and terminating the task when a specific level of difficulty cannot be completed (Gonthier et al.,

2018; Pickering, 2006).

Memory span tests use the all-or-none scoring method (Conway et al., 2005). In this approach, if a child fails to recall

a memory item or recalls it in the incorrect order, that item is marked as a failure. Such failures can lead to task termination,

potentially affecting the accuracy of assessments of children’s working memory abilities. Alternatively, one procedure involves

presenting all test questions of various difficulty levels in random order to each child (Conway et al., 2005; Unsworth et

al., 2009). However, this method may frustrate younger children or those with lower working memory capacity when they

encounter difficult questions, reducing their motivation to complete the task (Gonthier et al., 2018).

This study introduced a computerized complex span task designed to measure the working memory abilities of children

aged 4 to 7 years and analyzed its reliability and validity by integrating data from multiple research projects and a master’s thesis. In addition, this study explored the development of working memory in Taiwanese children aged 4 to 7 years. A total of

323 typically developing children (164 boys) from North Taiwan participated in the study, and they were divided into age groups

of 4, 5, 6, and 7 years. The study employed the animal-color span task, adapted from Camos and Barrouillet (2011), in which

the children alternated between a storage task (animal memory) and a processing task (color naming) within a limited time.

At the end of the task, the children were required to recall the memory items in the correct sequence. Scoring for the task was

strict. Points were awarded only if both the color naming and animal recall sequences were correct. In addition to the animalcolor

span task, all participants completed four additional memory and cognitive assessments, namely the Digit Forward Span

Task (DF), the Digit Backward Span Task (DB), the Working Memory Subtest of the WPPSI-IV, and the TONI-4 Nonverbal

Intelligence Test.

The distribution of the children’s performance on this task followed a normal curve, suggesting that the sampling was

effective. Reliability analysis demonstrated strong internal consistency for the task, with a Cronbach’s α of 0.76 and good splithalf

reliability (r = .77). Age-based analyses revealed consistent reliability across the age groups. Convergent validity analysis

indicated significant positive correlations of this task with the DF task, the DB task, the working memory subtest of the WPPSIIV,

and the TONI-4 Nonverbal Intelligence Test. These findings indicate that the task effectively measures individual differences

in short-term memory, working memory, and nonverbal intelligence.

Age discrimination and item response theory (IRT) were employed to evaluate the construct validity of the animal-color

span task. On the basis of IRT, the task’s difficulty increased progressively with the span levels, aligning with the Rosch

model and demonstrating strong construct validity. Moreover, the conversion of item pass probabilities into item difficulty

and a participant ability distribution yielded results that approximated a normal distribution. According to classical test

theory, discrimination indices for spans 2 and 3 were high, indicating strong item discrimination at these levels. Most children

successfully completed span 1 but faced limitations at spans 2 and 3. They considered span 4 to be challenging. Age-based

analysis further revealed that children aged 4, 5, 6, and 7 years achieved the approximate maximum spans 1, 2, 2, and 3,

respectively, which aligns with expected developmental trends. One-way ANOVA showed a significant increase in working

memory capacity from ages 4 to 7 years, indicating that the task effectively captures the maturation of working memory.

These results demonstrate that the animal-color span task developed in this study, a computerized complex span task, is

suitable for assessing working memory in children aged 4 to 7 years. The task demonstrates good reliability and validity and

reflects developmental differences in working memory. In addition, the computerized complex span task offers several other

advantages. (1) Theoretically, it aligns with the working memory model by incorporating both storage and processing tasks,

controlling the cognitive load of processing tasks (Camos & Barrouillet, 2011), and measuring children’s ability to resist

interference and maintain attentional control during the memory retention stage (Jarrold et al., 2011). (2) Methodologically,

the stimulus size, presentation time, interval time, and task termination for the storage and processing tasks are all computercontrolled,

which ensures standardized test procedures and reduces errors caused by human subjectivity. (3) In terms of practical

application, the standardized format enables researchers in different locations to implement consistent testing procedures (Bailey,

2012), facilitating cross-cultural and cross-study comparisons. (4) In future applications, the task’s standardized features can be

further developed into online or group testing formats that do not require experimenter assistance.

This study adapted only one version of the animal-color span task designed by Barrouillet et al. (2009) and Camos and

Barrouillet (2011). The other two versions of the task, which involve different processing conditions, were not included.

In addition, the complex span tasks developed in the aforementioned studies were originally intended to investigate the

mechanisms of working memory development in children aged 5 to 7 years. This study extended the applicability of one version

of the task downward to include 4-year-old children. However, additional research is needed to determine whether this task is

suitable for children younger than 4 years or those older than 7 years.