This chapter describes different script types that are involved when a person X is accompHshing a particular task Y. We refer to concepts and ideas from dis- tributed cognition theories. It is assumed that individuals are holding internal scripts that guide them in the way they process tasks they are faced with, and these internal scripts are standing in a complex relationship to the external scripts provided by an artifact or by other persons. Three factors are regarded as crucial in order to describe the accomplishment of a task, namely (a) the actual activity, (b) knowledge underlying the activity, and © the executive function, a (meta-)cognitive instance that is setting the goals for the task and controls the system's task accomplishment. For each of these three main fac- tors, several sub-categories are introduced, on which two script approaches are compared. The first approach represents the socio-technical environment Memory Aiding Prompting System (MAPS) designed to support individuals with cognitive disabilities in accomplishing everyday tasks with a focus on “tools for living”. The second approach, the so-called collaborative argumen- tation script, represents a computer-supported collaborative inquiry learning environment to facilitate students' collaborative argumentation with a focus on “tools for learning”. Implications of the comparison for the design of external scripts are derived and directions for future research are discussed. p. 1

Research on scaffolding tools has often adopted a technology-centered approach. Typically, individuals are provided with a technological tool and asked to perform a specific task, followed by measuring task performance as a function of using the tool or not (Pea, 2004). The personal development of the individual as well as changes of the context as a function of the interac- tions between the individual and the tool (i.e., an individual facing a new p. 1

situation after having used a tool) are rarely subject to theorizing and re- search. Salomon (1990) described the latter instance as the effects with tools which stand in contrast to effects q/tools, meaning the cognitive residuals that an individual holds after having interacted with a tool. These cognitive residuals then describe “learning” in a deeper sense. p. 2

To understand how an individual accomplishes a task, it is necessary to take into account the differ- ent factors that contribute to task accomplishment. These factors are com- prised of the technological device, the target individual herself, as well as the context in which the individual uses a particular technology (cf Stahl, 2002). p. 2

To conceptualize the complex interplay between these factors, we refer to the term script since it has been used in all three disciplines that can contrib- ute to solving this problem, namely psychology (Schank & Abelson, 1977), education (O'Donnell, 1999), and computer science (Ayala, this volume; Miao, Hoeksema, Hoppe, & Harrer, this volume). Although scripts are con- ceptualized differently in the three domains (see F. Fischer, Kollar, Mandl, & Haake, this volume), they share in common being seen as structures guiding sequences of activities. In other contexts, scripts are referred to as checklists (G. Fischer, Lemke, Mastaglio, & Morch, 1991). How these ap- proaches differ is in the question of where this guiding structure resides (in the mind of an individual vs. in the mind of the designer of an externally provided script vs. in the design of an artifact). The basic aim of this article is to articulate a perspective of an individual accomplishing a particular task as being guided by (a) the internal scripts individuals are holding with re- spect to the target activity, (b) the external scripts that are provided in the external surround of the actor(s), and © an interplay between those internal and external scripts. p. 2

The chosen scenarios point to a distinction between tools for living and tools for learning (Carmien, 2005). Tools for living are external artifacts that empower human beings to do things that they could not do by themselves without that individuals are required to internalize the knowledge residing in p. 2

these artifacts (Engelbart, 1995; Norman, 1993); they support distributed cognition or distributed intelligence (Pea, 1993), i.e., they serve as artifacts that augment a person's capabilities within a specific task for which an in- ternalization is not required or aimed at (e.g., a hand-held calculator). Tools for living can be tailored to specific tasks and to specific individuals. Tools for living do not change over time, remain a constant factor during task ac- complishment and are rarely abandoned (Carmien, 2005). In contrast, tools for learning support people in learning a new skill or strategy with the ob- jective that they will eventually become independent of the tool. Tools for learning often serve a scaffolding function (Pea, 2004) meaning that the strategy that is represented in the tool should be gradually internalized by the learners. p. 3

We live in a world of distributed cognition (Salomon, 1993; Hollan, Hutchins, & Kirsch, 2001; G. Fischer, 2003; Pea, 2004): the shopping list that “remembers” for us, the speedometer on our car, the posi- tion of the toggle on our light switch. p. 3

In his person-plus-siirroitnd conception, Perkins (1993) adopts a sys- temic view on cognition that goes beyond the individual actor: A system engaging in cognition usually consists of an individual (person-solo) and his immediate physical and social surround. This surround might include tools (such as hand-held calculators, spelling correctors, prompting systems, Mathematica software) as well as other persons (person-plus-surround), and the person-solo and its surround are standing in a complex interplay. To per- form a task, it matters less where the needed knowledge is represented - what counts are the access characteristics of that knowledge, i.e., how easily the system consisting of a learner and the immediate social and artifactual surround can access the relevant knowledge. For example, a person might consider a hand-held calculator as harboring the necessary knowledge to compute 3532*32131, and estimate that using the hand calculator requires less effort than calculating mentally. A system can further be characterized as dependent on which of its components has the executive function with respect to the task being accomplished. By executive function, Perkins (1993) means the (meta-)cognitive control over the system's actions. For p. 3

example, a French language book can take over the executive function for the system consisting of an individual learner and the book when it includes orders like “conjugate 'aller'”. According to Perkins, transferring knowledge to an external tool is adequate if the tool only performs routine tasks that cost too much to internalize (e.g., some mathematical calculations). Higher- order knowledge (e.g., knowledge about argumentation), as opposed to knowledge about routine tasks, should however reside in the person-solo (or be internalized by the person-solo), and not be transferred to the surround in order to give the individual the opportunity to internalize this knowledge and to be able to transfer this knowledge to different upcoming situations. The person-solo should be able to access this knowledge in situations in which an external tool is not present, i.e., to hold accessibility of the relevant knowl- edge as high as possible for different situations. p. 4

To describe situations in which an individual together with an external artifact accomplishes a particular task, scripts in various forms come into play. Instructional psychology (e.g., O'Donnell & Dansereau, 1992) uses the term script to describe instructions providing individuals (mostly members of a group) with procedural information with respect to performing a specific task (e.g., a manual for creating a table in WORD). These scripts can for ex- ample be represented graphically in a computer-based learning environment or can be given by a teacher's oral instructions. Scripts are - at least when they are presented for the first time - located in the external surround of the individual, aiming at improving an individual's (or a group's) performance with respect to a specific task. Considering the term as used in cognitive psychology (Schank & Abelson, 1977), scripts can be seen from a person- solo perspective as well: Most people already possess knowledge guiding them how to act in specific situations and in performing a specific task be- fore actually performing it. For example, to use a PDA properly, one needs to have prior experiences concerning how to scroll down a menu, open files, etc. In the following, we elaborate in depth the importance of scripts for an individual performing a particular task, first talking about scripts residing in the person-solo (internal scripts), then about scripts residing in the person- solo's surround (external scripts) and finally provide thoughts about their interplay. p. 4

From a person-solo perspective, the term script describes the knowledge and strategies that an individual possesses and which guides actions and un- derstanding in a specific situation (see Kolodner, this volume). In cognitive psychology, “a script is a structure that describes appropriate sequences of events in a particular context. A script is made up of slots and requirements p. 4

about what can fill those slots. The structure is an interconnected whole, and what is in one slot affects what can be in another” (Schank & Abelson, 1977, p. 41). Schank and Abelson (as well as Schank, 1999) use the term predomi- nately with respect to rather well-defined situations, the knowledge about which is acquired through repeated experiences with similar situations and which can be assumed as being culturally shared to a certain extent (e.g., a “restaurant script”). However, they also introduced personal scripts, mean- ing personal knowledge and strategies that guide an actor in acting in a situation that perhaps only herself interprets in this specific way and which is not culturally shared. For example, person A might possess knowledge of how to attack other arguments by creating counterarguments, whereas per- son B holds knowledge guiding her in finding an integration of different viewpoints. Such personal scripts can be highly flexible - experiencing an impasse can quickly trigger a change in the sequence of the personal script so that a different sequence gets instantiated. p. 5

Referring to Schank and Abelson's (1977) notion of personal scripts, in- dividuals may hold scripts for many situations they have experienced before. In our view, a script can be more or less flexible, well- or ill-defined de- pending on at least three conditions: (a) the stability of the previous experi- ences collected in similar previous situations, (b) the individual's abilities to abstract and generalize from these specific situations to similar new ones, and © the degree of structuredness or openness of the particular situation to rather situated actions and reactions. There can occur problems with an indi- vidual's internal scripts. First, internal scripts might not yet be well devel- oped because the individual did not go through a specific situation often enough to develop an internal script already solid enough to prescribe a defi- nite sequence of activities. This might be true for a middle school student who just started to learn algebra and has not yet developed an internal script concerning how to solve equations with two unknowns. Second, an internal script might not be adequately activated, perhaps because a person is per- forming two tasks simultaneously ending up with two scripts competing for too limited cognitive capacity. A third problem occurs when internal scripts are inaccessible or no longer accessible at all, as might be the case for people having had an accident that resulted in severe brain injury. In that case, in- ternal scripts, for example for using public transportation, might not be ac- cessible any more and can provide an opportunity for an external device de- signed to support an accomplishment of this task. A fourth problem could be that an internal script can be activated that does not fit current realities, for example a person with cognitive disabilities having activated the “board the express bus”-script but arriving at a bus stop that serves only local busses or a student creating a summary of a text when the actual task is to discuss strengths and weaknesses of the text. Fifth, in a collaborative learning see- p. 5

nario, collaborators might have activated inadequate or maybe too heteroge- neous internal scripts which hamper interaction, collaboration, and in the end learning. For example, when learners have the task of understanding the concepts of velocity and gravity by manipulating a computer model of a ball (similar to the task that was used by Roschelle & Teasley, 1996), one learner might have activated a trial-and-error-like internal script, whereas the other learner might have activated an internal script that guides her in thinking about the concepts in a more theoretical sense. Depending on the nature of the misfit of an internal script with respect to the external task, whatever of the five problems just described might have caused it, technology can help to provide external scripts to complement those deficient or inadequate internal ones. p. 6

How much of this is metaphorical, and how much actually represents our internal cognitive structures? p. 6

In contrast to cognitive psychology (Schank & Abelson, 1977), instruc- tional psychology (O'Donnell & Dansereau, 1992) as well as computer sci- ence (Ayala, this volume; Carmien, 2006b) use the term script to describe guidelines in the surround of an individual or a group of individuals that provide procedural support for accomplishing a specific task or a class of tasks. p. 6

External scripts do not always have to be as constraint-based or prescriptive as the script developed by O'Donnell and Dansereau (1992). Other scripts rather provide affordances (Norman, 1993) for particular activities to be carried out by an individual without explicitly stating “Now do X”, thereby being more permissive in nature. For example, scripts in inquiry-based learning environments tend to be rather open in that they afford very different activities to be conducted by the learners. Learners can engage in exploring information, in conducting ex- periments, in manipulating simulations, etc. What activities and what se- quences of activities a learner is realizing depends on the structure of his internal script. It is this interplay between externally present or induced scripts and the individuals' internal scripts that is of interest in the next sec- tion. p. 7

We claim (1) that the design of an external script must take into account the internal scripts of the individuals that will be utilized to accomplish a specific task and (2) that it is not adequate to regard the interplay of internal and external scripts as a static relationship. Different individuals hold differ- ent internal scripts that can be complemented only by different external scripts, and in the case of scripts that are tools for learning, portions of the external script become more and more internalized by individuals, becoming encoded in their internal script with respect to perform a specific task. In the case of individuals with cognitive disabilities the internal scripts (innate abilities and skills) differ from the internal scripts of non-handicapped indi- viduals in both content detail and in how to be best triggered externally. In the second, collaborative argumentation scenario we present later, two learn- ers holding low-level internal scripts about how to engage in collaborative argumentation are guided by an external collaboration script to debate about the contents of a web-based collaborative inquiry learning environment. From a systemic perspective, the learners together with the external collabo- ration script form a person(s)-plus-system. As both learners repeatedly fol- low the rules of the external collaboration script, they might develop a more sophisticated internal script on how to perform this task. The executive function may shift gradually from the external collaboration script to the learners' personal cognitive systems, resulting in the artifact (the external collaboration script) becoming less and less important and learners being enabled to engage in fruitful discussions without being guided by an external collaboration script. p. 7

In the cognitive disabilities scenario, individuals lack the ability to detect similarities between a situation, in which an external script once helped and a similar new situation. Then, there is no opportunity to internalize contents from the external script, and no gradual shift of script information from the surround to the person-solo can occur. As a consequence, the external script has to remain active (e.g., can not be faded out) and accessible over time to support individuals in accomplishing the task again and again. p. 8