Introduction

The concepts of curiosity and interest have both received increasing attention in the literature of motivation and education [1]. Curiosity has been shown to positively affect learning outcomes and processes [2]. Curiosity is related to higher academic performance on standardized tests [3] and academic persistence [4]. Likewise, interest supports learning in different content areas [5], and has been shown to facilitate a critical cognitive and affective motivational variable that aids attention [6]. Despite an increasing amount of work on these topics in recent years, a critical issue remains in the field: lack of consensus about how researchers should conceptualize these terms [7–12]. Although there is a view that we do not necessarily need to strictly define these terms to progress the field [13, 14], inconsistent use of the language may hinder effective scientific communications among researchers [8–15]. In addition, thinking about the definitions of these terms may shed new light on the psychological processes underlying the states of curiosity and interest.

In the classical literature, curiosity has been explained within the framework of drive reduction theories, treating it like an appetite analogous to other primary needs such as hunger, [16]. Further it is proposed that curiosity is the pleasant experience of novelty seeking and as such is an optimal arousal state lying in between feelings of anxiety and boredom [17]. Additionally, Loewenstein describes curiosity as associated with the identification of unknown pieces of information (i.e. knowledge gap) [7]. Another approach states that a dynamic subsystem regulates attentional focus through a spontaneous learning process, thus curiosity is the part of a larger unconscious mechanism [18].

Research on interest has been mainly developed in the literature of educational psychology. Similar to research on curiosity, there have been different perspectives on how interest should be conceptualized and theorized. For example, the four phase model of interest development, one of the most prominent interest theories in the literature, supposes that there are four phases in the development of interest: (1) triggered situational interest; (2) maintained situational interest; (3) emerging individual interest; and (4) well-developed individual interest [19]. The distinction between situational interest (1 & 2) and individual interest (3 & 4) is critical to the model. Situational interest is conceptualized as focused attention triggered by environmental stimuli, individual interest is conceptualized as a predisposition for reengaging with a particular topic. Krapp conceptualizes interest by connecting it to the person’s growing awareness of the self. A critical element in his conceptualization is the integration of ones’ self and the activities one is interested in [20]. The Expectancy-value Theory [21, 22] examines task interest by considering the influence of the subjective value of certain activities on motivation and achievement in school. Interest is generally examined by considering individual differences in engagement with educational activities and motivation. Another prominent model of interest, the self-regulation of motivation model [23], conceptualizes interest as a resource for self-regulation and focuses on people’s ability to self-generate interest.

Distinguishing curiosity and interest is the subject of much discussion. One common perspective is that curiosity is a momentary motivation to explore novel or puzzling phenomena [24, 25], whereas interest represents a more long-term developmental process, with emphasis on its stability in personality [26]. In other words, curiosity is sometimes conceptualized as immediate experiences in response to stimuli in the external environment (e.g., novel puzzles) while interest represents more active engagement within a learning context [19]. However, it is still unclear how in-the-moment experiences generated from interest (often called situational interest) are related to curiosity. In addition, this idea does not clearly explain how trait-level curiosity (i.e., trait curiosity; [27]) is distinguished from developed interest. As noted by Ainley, shared underlying characteristics of curiosity and interest (e.g., attentional processes and exploratory behaviour) are intertangled in infancy and early childhood; however, the experiential states associated with trait curiosity and interest diverge in later educational contexts [10].

Another discussion about curiosity and interest concerns whether they are instinctive (externally instigated by one’s environment) or intentional (internally instigated; [28]). While children’s curiosity is characterised as an exploratory behaviour, especially between ages 4 and 6 years, individual interests (dispositions towards reengaging with specific topics) do not arise until adolescence or adulthood [29]. From childhood to adulthood therefore, curiosity and interest have been reflected differently: in childhood curiosity is viewed as instinctive exploratory behaviour in response to external stimuli, and in adulthood interest is seen as intentional, self-motivated exploration. However, Peterson and Cohen define domain-specific curiosity as an active and intentional experience [30] and curiosity is defined as a conscious investigation and unspecified exploration of the environment [14]. Therefore, the terms can both be used to refer to intentional, internally-motivated behaviour or instinctive, externally-motivated behaviour.

The lack of consensus poses a challenge to empirical investigations of curiosity and interest, which need to “measure” these constructs in some way. For example, curiosity and interest are often examined together by self-reported measures. One such instance is the Interest-Deprivation Type Epistemic Curiosity scale, which distinguishes interest-type vs deprivation-type of curiosity [31]. As the name indicates, in this scale, interest is treated as one component of trait curiosity. Likewise, Litman and Spielberger, showed that interest emerges in measures of curiosity (i.e., noted by Berlyne in his definitions of epistemic curiosity, defined as a “drive to know” in the presence of a knowledge gap, and perceptual curiosity, defined as “the curiosity which leads perception of stimuli” via the tactile stimulation of humans and animals) such that curiosity is similar to triggered interest [32]. However, it is argued that interest has a broader range of triggering variables not limited to collative ones [1–8]. Interest is also often assessed by a subscale of intrinsic motivation [33] but the boundary between intrinsic motivation and interest is also unclear. Despite numerous self-report measures (e.g., State-Trait Personality Inventory; [34], Curiosity/interest in the World; [35], Epistemic Curiosity Scale; [27]) as well as task-based assessments/manipulations (e.g., trivia questions), there are no agreed-upon measures of curiosity and interest: they are generally based on subjective judgements or interpretations of researchers [28]. The issue is not limited to self-reported measures. Even for studies that use physiological or neuroscientific methods (e.g., eye-tracking, functional magnetic resonance imaging; [36, 37]), there are no agreed-upon indicators of curiosity and/or interest.

The long-lasting debate, disagreement, and confusion about the definition of curiosity and interest poses a fundamental question: Why is it so difficult to define curiosity and/or interest? A reward-learning framework of knowledge acquisition [14], which was recently proposed to explain the mechanistic process underlying knowledge acquisition behavior, could give us a clue. According to the reward-learning framework, people seek information as a consequence of the reward-learning (reinforcement-learning) process—the framework presupposes that information is inherently rewarding and, as a result, people expect information-seeking behavior to bring about reward. This inherent reward value of information may be driven by uncertainty (or because acquiring it resolves a knowledge gap). In addition, the framework clarifies the mechanisms by which people establish a long-term commitment to information seeking, explaining why people engage with a certain topic for a long period of time without any extrinsic rewards. Specifically, the framework suggests that increased knowledge enhances both the expected value of new upcoming information and people’s ability to understand it, creating a positive feedback loop of information-seeking behavior. Importantly, the framework explains various behaviors that people typically attribute to “curiosity” and “interest” without using such constructs (e.g., the framework does not suppose any elements of “curiosity” or “interest” in the mental process). These behaviors are solely explained by the interaction between reward-learning and knowledge expansion processes. Given this, what are curiosity or interest? According to the reward-learning framework, curiosity and interest are “subjective psychological constructions” of these mental processes [14]. People do not typically have direct access to the reward-learning process underlying knowledge acquisition behavior. However, the underlying reward-learning process produces a myriad of subjective experiences, and from these subjective feelings, people psychologically “construct” various concepts/languages that are useful to explain their subjective feelings and behavior [38]. Curiosity and interest are considered as two such concepts/languages.

This framework effectively explains the fundamental difficulty of defining curiosity and interest: They are hard to define because curiosity and interest are overly subjective categorization of ambiguous feelings. In fact, curiosity and interest are naïve concepts that laypeople have used long before the scientific investigation of these concepts started. Like much other lay language (e.g. “enjoyment”) such naïve terms do not have to have strict scientific definitions. Therefore, while we may be able to discuss and develop an agreed-upon definition, we should not expect that there are correct definitions of curiosity and interest. In other words, if there are two different perspectives to define these terms, there is no way to decide which is right or not. Note that this idea is not novel—in other fields (e.g., emotion research), psychological construction is a major perspective used to understand psychological constructs [39]. This perspective is also quite popular in philosophy of mind (e.g., scientific realism and the plasticity of mind, [40]).

At the same time however, because these terms are developed separately in daily language, it is likely that this results from people having somewhat distinct feelings (albeit some overlap) relating to knowledge acquisition, i.e., different experiences of their knowledge acquisition process. Our daily language does not develop in a vacuum—if lay people can distinguish two concepts, there is good possibility that these two concepts reflect (at least partly) different psychological processes [14]. Therefore, although lay people do not have direct access to precise mental processes, scrutinizing lay people’s definitions of curiosity and interest may provide us with some insights into how the knowledge acquisition process is organized in our mind. Examining lay perspectives may also provide scientific researchers with a good basis to establish agreed-upon scientific conceptualizations of curiosity and interest if they wish. If scientific definitions of curiosity and interest deviate substantially from what lay people believe they are, for example, researchers (especially researchers in applied fields) would have difficulty in effectively communicating their ideas with the general public. In that case, there is no logical reason for researchers to label them as “curiosity” and “interest” (i.e., researchers should use different technical terminologies). It is also worth noting that lay people’s belief is often a powerful predictor of their behavior, because people make a decision based on their own belief, not on an externally defined scientific concept [41–43]. As such, understanding people’s beliefs about curiosity and interest could help us develop a theory that predicts their behavior in their daily life.

The purpose of the current study is to conduct a preliminary and exploratory investigation on how lay people define curiosity and interest. We asked participants to define curiosity and interest in their own words, and examined the similarities and differences of these terms in a bottom-up manner. There are several studies that examined people’s perceptions about curiosity/interest [43, 44]. Kashdan et al. examined the relationship between self-ratings and other ratings (provided by friends and parents) of a person’s curiosity traits and found moderate correlations between them, indicating that people have a common idea of what curiosity means [44]. Thoman et al. examined people’s implicit theory of interest regulation—whether people believe that they can change and regulate their own interest or not [43]. They found that people who believe that interest can be changeable used more interest-regulation strategies when faced with a boring task, suggesting the importance of lay-people’s beliefs about curiosity/interest. Most closely related to our work, Post and Walma van der Molen. interviewed schoolchildren asking them to explain what curiosity means to them [45]. They found that children’s conception of curiosity mainly concerns the social domain (e.g., other people’s private affairs), rather than the educational domain (which the concept of interest may be more strongly related to). However, there has been a lack of research that directly examined potential commonalities and differences in lay people’s perception of curiosity and interest. Because participants were not prompted in any other way than the structured open-ended question, whatever responses the participants produced were presumed to represent their psychological reality, without using any follow-up questions. A qualitative approach may be one of the best ways to capture the definition and interpretation from these free texts. Qualitative approaches have become increasingly common in social studies, and researchers have proposed various different methodologies (e.g. pragmatism of the pluralistic approach, interpreting data pluralistically see [46]). Qualitative techniques provide rich data to evaluate studies and generate hypotheses [47] and give researchers an opportunity to understand the concepts deeply [48]. Unlike quantitative methods, the focus is not on confirming a theory—rather, the purpose is to generate hypotheses by valuing the idiosyncratic interpretations of researchers. We used thematic analysis from Braun and Clarke’s approach [49] to ensure an in-depth exploration of the data, whilst enabling the research to capture a breadth and diversity of views.

Methods

The study was approved by the University of Reading Research Ethics Committee (reference number 2016-109-KM).

Results

Overview of themes

The participants’ interpretations were captured in two main themes regarding the description of curiosity and interest: (1) curiosity is an active feeling and interest is a stable feeling; (2) curiosity is directed toward uncertainty and interest is directed toward certainty when you want to learn (see Fig 1). Each theme highlighted a major aspect of the respondents’ perspectives on the differences of curiosity and interest; however, there were areas of conceptual overlap, which we will discuss later. Below, we provide an explanation of the themes, along with example quotes.

Download:

• PPT
  PowerPoint slide
• PNG
  larger image
• TIFF
  original image

Fig 1. Diagram showing the transcript topic (level 1), themes (level 2), sub-themes (level 3), and higher-level codes (level 4) [49].

https://doi.org/10.1371/journal.pone.0256632.g001

Discussion

This study aimed to understand naïve participants’ beliefs about curiosity and interest. Although the terms are often considered to be separate concepts, the subjective experience of each term by naïve participants has not been examined in the literature—while experts and self-report scales defined these terms based on their own theoretical perspectives, relatively little is known about their natural meaning, discourse, and how they are described by naïve participants. The present results indicate that people ascribe somewhat distinct experiences to curiosity and interest. For example, while curiosity is considered to be active feelings towards uncertainty, interest is considered to be a more stable feeling than curiosity, which is more oriented towards certain things. We also found substantial overlap between the terms, e.g., both terms are closely related to knowledge acquisition process. In addition, the generated themes in the present research may help researchers establish agreed-upon scientific definitions that do not considerably deviate from people’s naïve understanding. This is not a trivial issue for applied researchers who are in constant communication with the general public.

Our results also suggest that curiosity is an active feeling which is further characterized as active thinking, a fleeting feeling that is the first feeling one experiences when confronted with an information gap, and a child-like emotion. This characterisation of curiosity supports previous theories of curiosity. Regarding curiosity as an active feeling, Berlyne classified curiosity with a four-way categorization in two dimensions (epistemic-perceptual curiosity and diversive-specific curiosity) [24]. These dimensions implicitly include active feelings, e.g., desire for change, seeking of stimulation, boredom, novelty and desire for knowledge. While Berlyne did not consider the intensity and frequency of feeling, the State-Trait Curiosity Inventory (STCI) did (though the item was “I feel mentally active”; [31]). Other researchers focus on similar active feelings of curiosity, e.g., the researchers [58], who proposed that practically curiosity involves acting and thinking differently to provide an intense desire to discover and engage in novel and challenging experiences. Regarding curiosity as a child-like emotion, Jirout and Klahr emphasized that curiosity in children is characterised as a natural feeling to discover the world [59]. Additionally, they state while children’s curiosity is instinctive (i.e., not under intentional control), this is different to adults’ curiosity, which can be intentionally directed in order to adapt to new situations [59]. Likewise, some researchers have linked curiosity with patterns of infant behavior where they attend to objects with specific physical properties like bright colors, sounds, human face and movement [60] and also novel objects (even when they have little no prior interaction with these objects, [10]).

Emotion theorists claim that while interest serves long-term developmental goals, curiosity relates to novelty and the possibility of actively broadening experiences [61]. The data seems to be consistent with this perspective. While the data from the present study indicated that curiosity was an active emotion, interest was defined as a passive, sustained and stable feeling. It is worth noting that some participants considered interest as a “passive” feeling as opposed to the active, transient feelings of curiosity. As we code and compare participants responses, we have come to the conclusion that we can interpret this aspect more as referring to the stability of interest. This is consistent with the previous research demonstrating that interest has a motivational function of maintaining engagement with the environment which allows us to adapt to new experiences that we experience through life [61, 62]. However, our interpretation of the data is open to further discussion.

Thematic analysis also revealed that interest was often considered a form of curiosity and was stronger than curiosity. It was stronger in terms of the intensity of desire and engaging for learning or discovering something. In line with previous research, although these terms were theoretically, empirically, and practically different, they were also highly related [8, 62, 63]. Curiosity and interest both fostered undivided attention and engagement towards new information, which complements findings that interest is thought to narrow attentional scope [64]. Our findings suggested that interest could be defined as involving more intense and sustainable attentional focus than curiosity—this idea is consistent with the perspective that interest is an long-term engagement with specific materials during which people enhance their awareness of the self [65].

Interest was associated with certainty about information that someone wanted to learn (i.e., people are interested in information related to something which they know a piece of information about), whereas curiosity was associated with uncertainty (i.e., people are curious about information related to something they do not know about). In the knowledge-gap model [7], curiosity resulted from the realisation that a piece of information was unknown. According to this account, curiosity is discussed in relation to exploration, uncertainty, tolerance of ambiguity, frustration and sensation seeking [66]. Supporting links between uncertainty and curiosity, there is agreement that curiosity is involved in risk-taking, trying new experiences and immersing oneself in situations with potential for new information or knowledge [25, 67, 68] while interest is involved in behavior that interacts with one’s current environment [61]. Moreover, interest supports people engaging with a diverse set of experiences long term, allowing people to reflect themselves in their current environment [9]. In contrast, curiosity (as openness to experience, novelty seeking and intrinsic motivation) allows people to grow through exploration [56–66, 69].

Our thematic analysis revealed that both curiosity and interest were understood as essential for learning or acquiring new information. This is in line with the literature on both curiosity and interest. Curiosity is defined as serving to motivate exploration and interaction with new information [56]. Likewise, interest is an emotion directed towards knowledge that motivates learning and exploration [9]. Prior reviews highlight the role of interest in encouraging people to think deeply and use good meta-cognitive skills [6, 9, 70]. Most studies concerning curiosity discuss curiosity in relation to overarching themes of information-seeking and gaining knowledge, e.g., epistemic curiosity [24], interest-deprivation type curiosity [27], and state-trait curiosity [71, 72]. Our results therefore also corroborate existing theories of curiosity, such as those that refer to it as the “cognitive appetite” [73], a “thirst for knowledge” [70] and/or an “appetite for knowledge” [74]. Our research is in line with previous studies that investigate curiosity and interest in terms of willingness to spend cognitive resources learning new information [75], as the main human motivation for learning [9] and academic performance across different learning environments [76].

Although speculative, these overall results suggest that the human knowledge-acquisition process may be organized in two different parts/stages—short-term/temporary information seeking based on information uncertainty and stable long-term motivation to engage in a task. A comprehensive account of information-seeking behavior requires consideration of both aspects [14]. This is consistent with the discussion based on the reward-learning framework of knowledge acquisition: While the framework supposes that information-seeking behavior is described by a reward-learning process driven by uncertainty, it also indicates that the fact that information is integrated into a person’s existing knowledge adds another layer to the process. Specifically, expanded knowledge increases the expected value of new information, sustaining long-term engagement in knowledge acquisition activities (e.g., information seeking). Our results seem to suggest that the former (short-term information seeking) is close to what people call curiosity and the latter (stable long-term information seeking) is close to what people call interest (though the distinction is not that clear in some respects).

Conclusion

This study investigated the naïve beliefs of people about the definition of curiosity and interest. Participants’ viewpoints revealed associations between the terms with active/stable feelings and uncertainty/certainty when you acquire new knowledge. Curiosity was considered active, was often equated to a child-like emotion, was a first feeling and a fleeting feeling. Interest was considered a sustainable and grounded feeling. Furthermore, we showed connections between uncertainty and curiosity when acquiring knowledge and found that curiosity was somewhat related to risk-taking behavior, trying new experiences, and wanting basic knowledge in something. In contrast, we showed connections between certainty and interest, and found that interest was related to long-term engagement with something, showing effort and action towards acquiring and sustaining knowledge over time. Although there are differences between curiosity and interest, the terms overlap in that they are both positive emotions, motivations, relate to acquiring knowledge and are both considered essential for learning (i.e. curiosity sparked further interest). Furthermore, curiosity and interest are different for adults and children. Specifically, curiosity and interest encourage individuals to improve and adapt to their environment. It is also clear that the terms are complementary and are likely to work in tandem; curiosity allows individuals to discover information and interest allows the consolidation and maintenance of that knowledge. Participants’ interpretations of the terms in their daily life can decrease practically unnecessary confusion regarding the definition of curiosity and interest in applied science (e.g. education, psychology, and neuroscience). This will help researchers to understand and consider peoples’ naïve belief about curiosity and interest when designing experiments in this field.

Supporting information