Antidepressants may do more than simply ease the symptoms of depression; they may actually make people less neurotic(神経症の、ノイローゼの)and more extroverted as well. It has been suggested that extroverts - people who are socially outgoing - have a more positive outlook on life and are less likely to be depressed. Other studies seem to show that people who are neurotic have a higher risk of developing depression. Both personality traits are affected by the neurotransmitter(神経伝達物質)serotonin, which is targeted by a widely prescribed class of drugs known as selective serotonin reuptake inhibitors (SSRIs)(選択的セロトニン再取り込み阻害薬).