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Matia Okubo

Senshu University, Psychology, Faculty Member

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Matia Okubo is a professor of cognitive psychology at Senshu University, Tokyo, Japan. His work focuses on laterality and everyday cognition. Specific interests include handedness, footedness, facial expressions, trustworthiness, attention, perception, and locomotion—to name a few. He also conducts research on martial arts, which fascinates him from his childhood.

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Università degli Studi "G. d'Annunzio" Chieti Pescara

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Stanford University

University of Vienna

University of East Anglia

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Banaras Hindu University, Varanasi

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Papers by Matia Okubo

The cheek of a cheater: Effects of posing the left and right hemiface on the perception of trustworthiness

Laterality: Asymmetries of Body, Brain and Cognition, 2017

Our cognitive mechanisms are designed to detect cheaters in social exchanges. However, cheater de... more Our cognitive mechanisms are designed to detect cheaters in social exchanges. However, cheater detection can be thwarted by a posed smile, which cheaters display with greater emotional intensity than cooperators. The present study investigated the role of hemifacial asymmetries in the perception of trustworthiness using face photographs with left and right cheek poses. Participants (N = 170) observed face photographs of cheaters and cooperators in an economic game. In the photographs, models expressed happiness or anger and turned slightly to the left or right to show their left or right cheeks to the camera. When the models expressed anger on their faces, cheaters showing the right cheek were rated as less trustworthy than cooperators (irrespective of cheeks shown) and cheaters showing the left cheek. When the models expressed happiness, trustworthiness ratings increased and did not differ between cheaters and cooperators, and no substantial asymmetries were observed. These patterns were replicated even when the face photographs were mirror-reversed. These results suggest that a cheater's fake smile conceals an uncooperative attitude that is displayed in the right hemiface, ultimately disguising cheater detection.

Processing Spatial Relations With Different Apertures of Attention

Cognitive Science, 2011

Neuropsychological studies suggest the existence of lateralized networks that represent categoric... more Neuropsychological studies suggest the existence of lateralized networks that represent categorical and coordinate types of spatial information. In addition, studies with neural networks have shown that they encode more effectively categorical spatial judgments or coordinate spatial judgments, if their input is based, respectively, on units with relatively small, nonoverlapping receptive fields, as opposed to units with relatively large, overlapping receptive fields. These findings leave open the question of whether interactive processes between spatial detectors and types of spatial relations can be modulated by spatial attention. We hypothesized that spreading the attention window to encompass an area that includes two objects promotes coordinate spatial relations, based on coarse coding by large, overlapping, receptive fields. In contrast, narrowing attention to encompass an area that includes only one of the objects benefits categorical spatial relations, by effectively parsing space. By use of a cueing procedure, the spatial attention window was manipulated to select regions of differing areas. As predicted, when the attention window was large, coordinate spatial transformations were noticed faster than categorical transformations; in contrast, when the attention window was relatively smaller, categorical spatial transformations were noticed faster than coordinate transformations. Another novel finding was that coordinate changes were noticed faster when cueing an area that included both objects as well as the empty space between them than when simultaneously cueing both areas including the objects while leaving the gap between them uncued.

Do you know your best side? Awareness of lateral posing asymmetries

People tend to show the left cheek to broadly express emotions while they tend to show the right ... more People tend to show the left cheek to broadly express emotions while they tend to show the right cheek to hide emotions because emotions were expressed more on the left than on the right side of the face. The present study investigated the level of awareness on the left- and right-cheek poses using the method of structural knowledge attributions. When asked to broadly express emotions for a family portrait, right-handed participants were more likely to show the left cheek than the right. On the other hand, when asked to conceal emotions to show a calm and reassuring attitude as a scientist, they were more likely to show the right cheek. After the posing session, participants selected the conscious level of their knowledge about posing from five categories: Random, intuition, familiarity, recollection, and rules. Most participants rated their knowledge as unconscious (i.e., either as random, intuition, or familiarity). The choice of the conscious level did not differ across posing or...

Regulatory focus and individual differences in working memory

The Proceedings of the Annual Convention of the Japanese Psychological Association

Are those who believe in physiognomy actually accurate in face-to-trait inference?

The Proceedings of the Annual Convention of the Japanese Psychological Association

The effect of semantic information of inattentional blindness

The Proceedings of the Annual Convention of the Japanese Psychological Association

Faces of glory: the left-cheek posing bias for medallists of Brazilian jiu-jitsu competitions

Laterality: Asymmetries of Body, Brain and Cognition

ABSTRACT Laboratory studies have shown that people tend to show the left side of their face when ... more ABSTRACT Laboratory studies have shown that people tend to show the left side of their face when asked to broadly express emotions, while they tend to show the right side when asked to hide emotions. Because emotions are expressed more intensely in the left side of the face, it is hypothesized that an individual’s intention to express or hide emotions biases the direction of lateral facial poses. The present study tested this hypothesis using photographic portraits of individuals experiencing emotional events in a naturalistic setting: the reception of medals in Brazilian jiu-jitsu competitions. Portrait photographs of Brazilian jiu-jitsu competitors were sourced online (N = 460) and were rated by two independent raters in terms of posing direction, emotional expression, and medal colour. Gold and silver medallists showed their left cheeks to the camera for commemorative photographs taken immediately after the medal ceremony. Positive emotions were expressed more often for gold medallists than silver ones. The left-cheek posing bias observed in the present study supports the hypothesis that the intended purpose of expressing or hiding emotions determines the direction of lateral posing biases, and extends the laboratory findings to situations in the real world.

Grotesque Impressions Enhance the Gaze Cueing Effect

International Journal of Social Science Studies, 2012

A non-predictive gaze cue produces a reflexive shift of attention to the gazed-at location. The p... more A non-predictive gaze cue produces a reflexive shift of attention to the gazed-at location. The present study used a modified version of Posner's attentional cueing paradigm (a gaze cueing paradigm) to investigate role of grotesque facial expressions on a gaze cueing effect involving induced fear. Grotesque faces were created by vertically shifting the position of one of the two eyes (Experiment 1, N =28) or both eyes (Experiment 2, N =28). The grotesque faces of Experiment 1 produced a larger facilitative effect of a gaze cue than did original faces, whereas the less grotesque faces of Experiment 2 did not. Cooper & Wojan (2000) have shown that one-eye moved faces produce much more grotesque impressions than two-eye moved faces. Results suggest that a grotesque facial expression, which may induce fear, automatically attracts observers' attention and facilitates processing of the gaze, ultimately enhancing the gaze cueing effect.

Assessment of cognitive load and the eﬃcacy of modality effects

The Proceedings of the Annual Convention of the Japanese Psychological Association

Effects of social anxiety on metaphorical associations between emotional valence and clothing brightness

Journal of Behavior Therapy and Experimental Psychiatry

BACKGROUND AND OBJECTIVES Individuals with social anxiety have various types of deficiencies in e... more BACKGROUND AND OBJECTIVES Individuals with social anxiety have various types of deficiencies in emotional processing. Diversity of deficiencies may imply that socially anxious individuals have malfunctions in fundamental parts of emotional processing. Therefore, we hypothesized that social anxiety contributes to deficiencies in building on the metaphorical relationship between emotional experience and brightness. METHODS We conducted a judgment task of valences of faces with manipulated clothing brightness (bright or dark). RESULTS A congruency effect between the emotional valence and clothing brightness was observed in participants with low social anxiety. However, this pattern was not found in participants with high social anxiety. The results suggested that a deficiency in metaphorical associations leads to maladaptive emotional processing in individuals with social anxiety. LIMITATIONS Our findings cannot be directly generalized to clinical populations. Such populations should be tested in the future studies. CONCLUSIONS We may expand Lakoff and Johnson's (1999) conceptual metaphor theory by showing the relationships between social anxiety and malfunction in metaphorical processing. Malfunctions in metaphorical processing could lead to various types of psychological disorders which have deficiencies in emotional processing.

Perception and belief about the colors of an ambiguous representation of "the Dress": The effects of other persons’ opinion, previous experience and culture

The Proceedings of the Annual Convention of the Japanese Psychological Association, Sep 20, 2017

The other race effect in the uncanny valley: Measurement of pupil size

The Proceedings of the Annual Convention of the Japanese Psychological Association

Age-related Differences in Neural Responses to Impression-incongruent Information about Others’ Trustworthiness

The Proceedings of the Annual Convention of the Japanese Psychological Association

Temporal characteristics of selective attention to threatening stimuli in social anxiety

The Proceedings of the Annual Convention of the Japanese Psychological Association

Gender differences in working memory disruption under social pressure

The Proceedings of the Annual Convention of the Japanese Psychological Association

Overestimation of the Subjective Experience of Time in Social Anxiety: Effects of Facial Expression, Gaze Direction, and Time Course

Frontiers in Psychology

It is known that threatening stimuli increase emotional arousal, resulting in overestimating the ... more It is known that threatening stimuli increase emotional arousal, resulting in overestimating the subjective experience of passing time. Moreover, facial expressions and gaze direction interact to create socially threatening situations in people with social anxiety. The present study investigated the effect of social anxiety on the perceived duration of observing emotional faces with a direct or an averted gaze. Participants were divided into high, medium and low social anxiety groups based on social anxiety inventory scores. Participants then performed a temporal bisection task. Participants with high social anxiety provided larger overestimates for neutral faces with an averted gaze than those with low social anxiety in the second half of the task, whereas these differences were not found for angry face with direct and averted gaze. These results suggest that people with social anxiety perceive the duration of threatening situations as being longer than true durations based on objectively measured time.

Can I Trust You? Laterality of Facial Trustworthiness in an Economic Game

Journal of Nonverbal Behavior

People tend to turn their left or right cheek to express or conceal emotions, respectively. We ex... more People tend to turn their left or right cheek to express or conceal emotions, respectively. We examined the lateral posing bias for displaying trustworthiness during a trust game in which participants and their virtual partners cooperated or did not cooperate with their counterparts to earn a monetary reward. Right-handed participants (N = 81) were asked to pose for a photograph and then play the trust game. Participants showed an overall left posing bias (i.e., showing their left cheek to the camera). The left cheek bias was more stable for participants that cooperated very little in the trust game (non-cooperators) than for those that cooperated a lot (cooperators). In the rating experiment (N = 28 and 25), non-cooperators showing their left cheek were rated equally as trustworthy as cooperators. On the other hand, non-cooperators who showed their right cheek were rated as less trustworthy than cooperators. These results suggest that non-cooperators intuitively use the left hemiface to exploit others in social interactions.

Cool Guys and Warm Husbands

Evolutionary Psychology, 2015

While smiling enhances women’s facial attractiveness, the findings are inconclusive for men. The ... more While smiling enhances women’s facial attractiveness, the findings are inconclusive for men. The present study investigated the effect of smiling on male facial attractiveness for short- and long-term prospective partners using East Asian and European samples. In Experiment 1 ( N = 218), where female participants rated male facial attractiveness, the facilitative effect of smiling was present when judging long-term partners but absent for short-term partners. This pattern was observed for East Asians as well as for Europeans. Experiment 2 ( N = 71) demonstrated that smiling male faces engendered an impression suitable for long-term partnership (e.g., high ratings of trustworthiness) while neutral faces produced an impression suitable for short-term partnership (e.g., high ratings of masculinity). We discuss these results in terms of opposing evolutionary strategies in mate choice: heritable benefit versus paternal investment.

Introduction of Bayesian statistics by using Hamiltonian Monte Carlo method for analysis of experimental data: Departure from t-test and analysis of variance

The Proceedings of the Annual Convention of the Japanese Psychological Association, Sep 22, 2015

The "face race lightness illusion": An effect of the eyes and pupils?

PLOS ONE

In an internet-based, forced-choice, test of the 'face race lightness illusion', the majority of ... more In an internet-based, forced-choice, test of the 'face race lightness illusion', the majority of respondents, regardless of their ethnicity, reported perceiving the African face as darker in skin tone than the European face, despite the mean luminance, contrast and numbers of pixels of the images were identical. In the laboratory, using eye tracking, it was found that eye fixations were distributed differently on the African face and European face, so that gaze dwelled relatively longer onto the locally brighter regions of the African face and, in turn, mean pupil diameters were smaller than for the European face. There was no relationship between pupils' size and implicit social attitude (IAT) scores. In another experiment, the faces were presented either tachistoscopically (140 ms) or longer (2500 ms) so that, when gaze was prevented from looking directly at the faces in the former condition, the tendency to report the African face as "dark" disappeared, but it was present when gaze was free to move for just a few seconds. We conclude that the presence of the illusion depends on oculomotor behavior and we also propose a novel account based on a predictive strategy of sensory acquisition. Specifically, by differentially directing gaze towards to facial regions that are locally different in luminance, the resulting changes in retinal illuminance yield respectively darker or brighter percepts while attending to each face, hence minimizing the mismatch between visual input and the learned perceptual prototypes of ethnic categories.

The cheek of a cheater: Effects of posing the left and right hemiface on the perception of trustworthiness

Laterality: Asymmetries of Body, Brain and Cognition, 2017

Our cognitive mechanisms are designed to detect cheaters in social exchanges. However, cheater de... more Our cognitive mechanisms are designed to detect cheaters in social exchanges. However, cheater detection can be thwarted by a posed smile, which cheaters display with greater emotional intensity than cooperators. The present study investigated the role of hemifacial asymmetries in the perception of trustworthiness using face photographs with left and right cheek poses. Participants (N = 170) observed face photographs of cheaters and cooperators in an economic game. In the photographs, models expressed happiness or anger and turned slightly to the left or right to show their left or right cheeks to the camera. When the models expressed anger on their faces, cheaters showing the right cheek were rated as less trustworthy than cooperators (irrespective of cheeks shown) and cheaters showing the left cheek. When the models expressed happiness, trustworthiness ratings increased and did not differ between cheaters and cooperators, and no substantial asymmetries were observed. These patterns were replicated even when the face photographs were mirror-reversed. These results suggest that a cheater's fake smile conceals an uncooperative attitude that is displayed in the right hemiface, ultimately disguising cheater detection.

Processing Spatial Relations With Different Apertures of Attention

Cognitive Science, 2011

Neuropsychological studies suggest the existence of lateralized networks that represent categoric... more Neuropsychological studies suggest the existence of lateralized networks that represent categorical and coordinate types of spatial information. In addition, studies with neural networks have shown that they encode more effectively categorical spatial judgments or coordinate spatial judgments, if their input is based, respectively, on units with relatively small, nonoverlapping receptive fields, as opposed to units with relatively large, overlapping receptive fields. These findings leave open the question of whether interactive processes between spatial detectors and types of spatial relations can be modulated by spatial attention. We hypothesized that spreading the attention window to encompass an area that includes two objects promotes coordinate spatial relations, based on coarse coding by large, overlapping, receptive fields. In contrast, narrowing attention to encompass an area that includes only one of the objects benefits categorical spatial relations, by effectively parsing space. By use of a cueing procedure, the spatial attention window was manipulated to select regions of differing areas. As predicted, when the attention window was large, coordinate spatial transformations were noticed faster than categorical transformations; in contrast, when the attention window was relatively smaller, categorical spatial transformations were noticed faster than coordinate transformations. Another novel finding was that coordinate changes were noticed faster when cueing an area that included both objects as well as the empty space between them than when simultaneously cueing both areas including the objects while leaving the gap between them uncued.

Do you know your best side? Awareness of lateral posing asymmetries

People tend to show the left cheek to broadly express emotions while they tend to show the right ... more People tend to show the left cheek to broadly express emotions while they tend to show the right cheek to hide emotions because emotions were expressed more on the left than on the right side of the face. The present study investigated the level of awareness on the left- and right-cheek poses using the method of structural knowledge attributions. When asked to broadly express emotions for a family portrait, right-handed participants were more likely to show the left cheek than the right. On the other hand, when asked to conceal emotions to show a calm and reassuring attitude as a scientist, they were more likely to show the right cheek. After the posing session, participants selected the conscious level of their knowledge about posing from five categories: Random, intuition, familiarity, recollection, and rules. Most participants rated their knowledge as unconscious (i.e., either as random, intuition, or familiarity). The choice of the conscious level did not differ across posing or...

Regulatory focus and individual differences in working memory

The Proceedings of the Annual Convention of the Japanese Psychological Association

Are those who believe in physiognomy actually accurate in face-to-trait inference?

The Proceedings of the Annual Convention of the Japanese Psychological Association

The effect of semantic information of inattentional blindness

The Proceedings of the Annual Convention of the Japanese Psychological Association

Faces of glory: the left-cheek posing bias for medallists of Brazilian jiu-jitsu competitions

Laterality: Asymmetries of Body, Brain and Cognition

ABSTRACT Laboratory studies have shown that people tend to show the left side of their face when ... more ABSTRACT Laboratory studies have shown that people tend to show the left side of their face when asked to broadly express emotions, while they tend to show the right side when asked to hide emotions. Because emotions are expressed more intensely in the left side of the face, it is hypothesized that an individual’s intention to express or hide emotions biases the direction of lateral facial poses. The present study tested this hypothesis using photographic portraits of individuals experiencing emotional events in a naturalistic setting: the reception of medals in Brazilian jiu-jitsu competitions. Portrait photographs of Brazilian jiu-jitsu competitors were sourced online (N = 460) and were rated by two independent raters in terms of posing direction, emotional expression, and medal colour. Gold and silver medallists showed their left cheeks to the camera for commemorative photographs taken immediately after the medal ceremony. Positive emotions were expressed more often for gold medallists than silver ones. The left-cheek posing bias observed in the present study supports the hypothesis that the intended purpose of expressing or hiding emotions determines the direction of lateral posing biases, and extends the laboratory findings to situations in the real world.

Grotesque Impressions Enhance the Gaze Cueing Effect

International Journal of Social Science Studies, 2012

A non-predictive gaze cue produces a reflexive shift of attention to the gazed-at location. The p... more A non-predictive gaze cue produces a reflexive shift of attention to the gazed-at location. The present study used a modified version of Posner's attentional cueing paradigm (a gaze cueing paradigm) to investigate role of grotesque facial expressions on a gaze cueing effect involving induced fear. Grotesque faces were created by vertically shifting the position of one of the two eyes (Experiment 1, N =28) or both eyes (Experiment 2, N =28). The grotesque faces of Experiment 1 produced a larger facilitative effect of a gaze cue than did original faces, whereas the less grotesque faces of Experiment 2 did not. Cooper & Wojan (2000) have shown that one-eye moved faces produce much more grotesque impressions than two-eye moved faces. Results suggest that a grotesque facial expression, which may induce fear, automatically attracts observers' attention and facilitates processing of the gaze, ultimately enhancing the gaze cueing effect.

Assessment of cognitive load and the eﬃcacy of modality effects

The Proceedings of the Annual Convention of the Japanese Psychological Association

Effects of social anxiety on metaphorical associations between emotional valence and clothing brightness

Journal of Behavior Therapy and Experimental Psychiatry

BACKGROUND AND OBJECTIVES Individuals with social anxiety have various types of deficiencies in e... more BACKGROUND AND OBJECTIVES Individuals with social anxiety have various types of deficiencies in emotional processing. Diversity of deficiencies may imply that socially anxious individuals have malfunctions in fundamental parts of emotional processing. Therefore, we hypothesized that social anxiety contributes to deficiencies in building on the metaphorical relationship between emotional experience and brightness. METHODS We conducted a judgment task of valences of faces with manipulated clothing brightness (bright or dark). RESULTS A congruency effect between the emotional valence and clothing brightness was observed in participants with low social anxiety. However, this pattern was not found in participants with high social anxiety. The results suggested that a deficiency in metaphorical associations leads to maladaptive emotional processing in individuals with social anxiety. LIMITATIONS Our findings cannot be directly generalized to clinical populations. Such populations should be tested in the future studies. CONCLUSIONS We may expand Lakoff and Johnson's (1999) conceptual metaphor theory by showing the relationships between social anxiety and malfunction in metaphorical processing. Malfunctions in metaphorical processing could lead to various types of psychological disorders which have deficiencies in emotional processing.

Perception and belief about the colors of an ambiguous representation of "the Dress": The effects of other persons’ opinion, previous experience and culture

The Proceedings of the Annual Convention of the Japanese Psychological Association, Sep 20, 2017

The other race effect in the uncanny valley: Measurement of pupil size

The Proceedings of the Annual Convention of the Japanese Psychological Association

Age-related Differences in Neural Responses to Impression-incongruent Information about Others’ Trustworthiness

The Proceedings of the Annual Convention of the Japanese Psychological Association

Temporal characteristics of selective attention to threatening stimuli in social anxiety

The Proceedings of the Annual Convention of the Japanese Psychological Association

Gender differences in working memory disruption under social pressure

The Proceedings of the Annual Convention of the Japanese Psychological Association

Overestimation of the Subjective Experience of Time in Social Anxiety: Effects of Facial Expression, Gaze Direction, and Time Course

Frontiers in Psychology

It is known that threatening stimuli increase emotional arousal, resulting in overestimating the ... more It is known that threatening stimuli increase emotional arousal, resulting in overestimating the subjective experience of passing time. Moreover, facial expressions and gaze direction interact to create socially threatening situations in people with social anxiety. The present study investigated the effect of social anxiety on the perceived duration of observing emotional faces with a direct or an averted gaze. Participants were divided into high, medium and low social anxiety groups based on social anxiety inventory scores. Participants then performed a temporal bisection task. Participants with high social anxiety provided larger overestimates for neutral faces with an averted gaze than those with low social anxiety in the second half of the task, whereas these differences were not found for angry face with direct and averted gaze. These results suggest that people with social anxiety perceive the duration of threatening situations as being longer than true durations based on objectively measured time.

Can I Trust You? Laterality of Facial Trustworthiness in an Economic Game

Journal of Nonverbal Behavior

People tend to turn their left or right cheek to express or conceal emotions, respectively. We ex... more People tend to turn their left or right cheek to express or conceal emotions, respectively. We examined the lateral posing bias for displaying trustworthiness during a trust game in which participants and their virtual partners cooperated or did not cooperate with their counterparts to earn a monetary reward. Right-handed participants (N = 81) were asked to pose for a photograph and then play the trust game. Participants showed an overall left posing bias (i.e., showing their left cheek to the camera). The left cheek bias was more stable for participants that cooperated very little in the trust game (non-cooperators) than for those that cooperated a lot (cooperators). In the rating experiment (N = 28 and 25), non-cooperators showing their left cheek were rated equally as trustworthy as cooperators. On the other hand, non-cooperators who showed their right cheek were rated as less trustworthy than cooperators. These results suggest that non-cooperators intuitively use the left hemiface to exploit others in social interactions.

Cool Guys and Warm Husbands

Evolutionary Psychology, 2015

While smiling enhances women’s facial attractiveness, the findings are inconclusive for men. The ... more While smiling enhances women’s facial attractiveness, the findings are inconclusive for men. The present study investigated the effect of smiling on male facial attractiveness for short- and long-term prospective partners using East Asian and European samples. In Experiment 1 ( N = 218), where female participants rated male facial attractiveness, the facilitative effect of smiling was present when judging long-term partners but absent for short-term partners. This pattern was observed for East Asians as well as for Europeans. Experiment 2 ( N = 71) demonstrated that smiling male faces engendered an impression suitable for long-term partnership (e.g., high ratings of trustworthiness) while neutral faces produced an impression suitable for short-term partnership (e.g., high ratings of masculinity). We discuss these results in terms of opposing evolutionary strategies in mate choice: heritable benefit versus paternal investment.

Introduction of Bayesian statistics by using Hamiltonian Monte Carlo method for analysis of experimental data: Departure from t-test and analysis of variance

The Proceedings of the Annual Convention of the Japanese Psychological Association, Sep 22, 2015

The "face race lightness illusion": An effect of the eyes and pupils?

PLOS ONE

In an internet-based, forced-choice, test of the 'face race lightness illusion', the majority of ... more In an internet-based, forced-choice, test of the 'face race lightness illusion', the majority of respondents, regardless of their ethnicity, reported perceiving the African face as darker in skin tone than the European face, despite the mean luminance, contrast and numbers of pixels of the images were identical. In the laboratory, using eye tracking, it was found that eye fixations were distributed differently on the African face and European face, so that gaze dwelled relatively longer onto the locally brighter regions of the African face and, in turn, mean pupil diameters were smaller than for the European face. There was no relationship between pupils' size and implicit social attitude (IAT) scores. In another experiment, the faces were presented either tachistoscopically (140 ms) or longer (2500 ms) so that, when gaze was prevented from looking directly at the faces in the former condition, the tendency to report the African face as "dark" disappeared, but it was present when gaze was free to move for just a few seconds. We conclude that the presence of the illusion depends on oculomotor behavior and we also propose a novel account based on a predictive strategy of sensory acquisition. Specifically, by differentially directing gaze towards to facial regions that are locally different in luminance, the resulting changes in retinal illuminance yield respectively darker or brighter percepts while attending to each face, hence minimizing the mismatch between visual input and the learned perceptual prototypes of ethnic categories.