Dull to Social Acceptance Rather than Sensitivity to Social Ostracism in Interpersonal Interaction for Depression: Behavioral and Electrophysiological Evidence from Cyberball Tasks

Abstract

Objectives: Impairments in interpersonal relationships in depression present as irritability, pessimism, and withdrawal, and play an important role in the onset and maintenance of the disorder. However, we know little about the neurological causes of this impaired interpersonal function. This study used the event-related brain potential (ERP) version of the Cyberball paradigm to investigate the emotions and neural activities in depressive patients during social inclusion and exclusion simultaneously to explore neuropsychological mechanisms. Methods: Electrophysiological data were recorded when 27 depressed patients and 23 healthy controls (HCs) performed a virtual ball tossing game (Cyberball) during which the participants believed they were playing with two other co-players over the internet. The Cyberball paradigm included two other conditions; inclusion during which participants received the ball with the same probability as the other players to experience a feeling of acceptance, and exclusion during which the participants experienced a feeling of ostracism when the other two players threw the ball with each other. The Positive and Negative Affect Schedule (PANAS) was used as a baseline and after each block during the Cyberball to assess positive and negative effects. In addition, a brief Need-Threat Scale (NTS) was used to assess the fulfillment of basic needs of subjects after each block and 10 min after ostracism. Moreover, the relationship between the ERP data of depression and clinical symptoms was analyzed. Results: Exclusion compared to inclusion Cyberball caused a decrease in positive affect and an increase in negative affect. The group differences were only found in the positive affect. Moreover, patients reported a lower level of basic needs than did HCs after social inclusion, but a similar level of basic needs after social exclusion. At the electrophysiological level, patients showed decreased P3 amplitudes compared to HCs in social inclusion, and P3 amplitudes were borderline negatively correlated with their scores of anhedonia symptoms. Limitations: A limitation of our study was that the subjects' criteria were different. Conclusions: The behavioral and electrophysiological results indicated that the interpersonal problems in depressive patients were mainly due to deficits in processing the pleasurable social stimuli rather than aversive social cues.

Keywords: cyberball; depression; event-related potential (ERP); social exclusion; social inclusion.

Figure 1

The Cyberball game and a schematic of the experiment program. (A) The Cyberball game: Participants are represented by a cartoon of hand at the bottom of the screen, and computer-generated players stand on either side. During the inclusion block, participant has a 50% chance of receiving the ball at each throw. While in exclusion condition, participant cannot catch the ball after receiving 10 throws. (B) A schematic of the time course of the experiment. After completing the demographics and basic measures, participant was asked to play the Cyberball game and report how they felt about the game. 10 min after the exclusion block, the Need-Threat Scale (NTS) was retested.

Figure 2

The self-reported feelings of patients and healthy controls on the two subscales of the (A) Positive and (B) Negative Affect Schedule (PANAS) during baseline and two blocks of the Cyberball tasks are plotted. (HCs, healthy controls).

Figure 3

Self-reported feelings on the Need-Threat Scale after each Cyberball block and 10 min after exclusion Cyberball block are shown for each group separately (HCs, healthy controls). (A) NTS in HCs and (B) NTS in depression.

Figure 4

The P3 average waves evoke d by inclusion and exclusion in depressive patients (red lines) and healthy controls (blue lines) at Fz, FCz, and Cz sites (A–C). The corresponding amplitudes histogram was shown atthe upper right (D). (HCs, healthy controls; D, depressive patients).

Figure 5

Amplitudes of P3 and BDI symptoms. The amplitudes of P3 were not correlated with the scores of Beck Depression Inventory (BDI), but were borderline negatively correlated with the scores of anhedonia symptoms for patients with depression.