To our knowledge, this study is the first to have used J-DERS to evaluate the patient’s function at each step of the process of emotional expression that is also affected by the presence or absence of alexithymia as assessed by TAS-20. Initially, upon comparison of the TAS-20 high- and low- scoring groups, we expected to only find a disruption in the third step of the process of emotional expression described by Kennedy-Moore and Watson (Fig. 1) [9]. In other words, we expected to only find a difference in the scores relating to the J-DERS subscale for lack of emotional awareness when comparing the two groups. However, we found significant differences both in the total J-DERS score and also for each of its subscales. This is the most important point to consider in this study, as it suggests that when there is a disruption of Step 3 (labeling and interpretation of response) illustrated in Fig. 2, functioning in the following steps can also be affected, which may also lead to disruption of Steps 4 and 5. Gratz and Roemer proposed that emotion regulation involved the following four abilities: (a) awareness and understanding of emotions, (b) acceptance of emotions, (c) ability to control impulsive behaviors and behave in accordance with desired goals when experiencing negative emotions, (d) ability to use situationally appropriate emotion regulation strategies flexibly to modulate emotional responses as desired in order to meet individual goals and situational demands [15]. These correspond to the four subscales of the J-DERs outlined in Table 1: (1) lack of emotional awareness, (2) nonacceptance of emotional responses, (3) limited access to emotion regulation strategies, and (4) impulse control difficulties [16]. The results of the present study suggest that, in patients indicated to have alexithymia or be in the intermediate zone, emotion regulation is hindered with regard to each of these four abilities. This means that when dealing with individual alexithymic patients in the clinical setting, therapeutic interventions for the alexithymia should probably be adapted to Steps 3, 4, or 5 as appropriate for each patient. The TAS-20 has three subscales, namely, DIF, DDF, and EOT. Together with the process of emotional expression, these three concepts are fundamental to the concept of alexithymia. DIF seems to correspond to a disruption in Step 3, while DDF to a disruption in Step 4. We hypothesized that when alexithymic individuals fail to use emotion as an indicator to deal with events due to their inability to identify emotions, they tend to focus on the circumstances and details surrounding events [17] and fall into EOT. In this regard, we hypothesized that EOT also corresponds to a disruption in Step 3 (Fig. 4). A comparison of the TAS-20 and J-DERS subscales showed that although DIF was correlated with all of the J-DERS total and subscale scores, DDF and EOT were not. This essentially means that the TAS-20 subscales do not measure the individual contributions of Steps 3, 4, and 5. In other words, TAS-20 essentially describes alexithymia as the sum of effects in Steps 3, 4, and 5. In accordance with this, our results indicate that using the J-DERS to evaluate each individual step may be more useful in the clinical setting. Since psychotherapies such as cognitive-behavioral therapy and supportive psychotherapy do not tend to produce good results with alexithymia, and based on the results of the present study, we suggest that alexithymia patients with a disruption in Step 3 could be prompted not to identify as “feelings” the “conscious perceptions of response” which occurs when emotions are aroused, but instead to notice the “bodily sensations” that they experience, and then to recognize, identify, and label these accordingly. For example, a potential method may be to prompt an alexithymia patient to write a description of an event, and then encourage them to learn what emotions would correspond to it. For a disruption in Step 4, a potential therapeutic intervention could involve using mindfulness to encourage the acceptance of emotion [18], while for a disruption in Step 5, a cognitive-behavioral treatment such as that proposed by Barlow [19] may be appropriate. In this way, therapeutic interventions can be tailored to target the disruptions in the various steps. We believe that if such therapies are successful, then alexithymic individuals may better their ability to express emotions, which can lead to allowing them to compare their emotions and consider how best to act, leading to a change in their behavior, and ultimately enabling them to better deal with potentially stressful situations and interactions. Administering therapeutic interventions tailored for the various steps in which disruptions exist when treating alexithymia and intermediate zone patients is important; however, further studies are required to investigate the emotional processing and modes of these therapeutic interventions. Moreover, it may be necessary to develop a new scale to evaluate the disruption of the process of emotional expression on an individual level. This study aimed to verify in which steps of the process of emotional expression disruptions existed in alexithymia—a condition closely connected with psychosomatic disorders and physical disease—and to clarify what methods would be appropriate for treating the disruptions in the various steps, so that effective therapeutic interventions can be administered. The results showed that in alexithymia, disruption can occur not only in Step 3, which is essentially the definition of the condition, but also in Steps 4 and 5. The present study had the following four limitations: First, this study assessed alexithymia using self-administered tests. Next, the presence of alexithymia was defined as a TAS-20 score of 52 or greater, which meant that the intermediate zone was also included in the TAS-20 high group. Additionally, patients with mental disease that presented with mainly physical symptoms were may have been inadvertently included. Finally, this was a retrospective study of cases at a single institution, which means that questions could be raised with regard to its external validity and generalizability. However, as differences were observed between the TAS-20 high group (which encompassed both alexithymia and the intermediate zone) and the TAS-20 low group with respect to their total and subscale J-DERS scores, we can say that the present study did succeed in clarifying the fact that in alexithymia, disruption also occurs in Steps 4 and 5, and not only in Step 3 as was previously reported. The present study provides a useful starting point for developing therapeutic interventions for alexithymia.