Since its conception in the mid-1980s, the American progressive metal band Dream Theater has produced numerous songs covering themes related to the human condition. A vibrant example is the ensemble's sixth record Six Degrees of Inner Turbulence (2002) with songs on alcoholism, stem-cell research, death, faith, loneliness and mental health. The record's title mainly refers to five mental illnesses (bipolar disorder, post-traumatic stress disorder [PTSD], dissociative personality disorder, schizophrenia and post-partum depression [PPD]) and the developmental disorder autism that are represented in the 42-min title track. The song is a continuous whole with separately named sections, with each, except the Overture, focusing on the experience and perception of the conditions mentioned above.

Some examples: About to Crash chronicles the story of a young woman with bipolar disorder. It is told by a related observer, who laments his inability to aid her and notes bipolar disorder's cyclic nature (‘He says I've never seen her get this bad’), as a manic period spirals out of control into severe depression (‘Once barely taking a break, Now she sleeps the days away’). This cycle is further emphasised by an uplifting reprise during which the woman exclaims: ‘I'm alive again, the darkness far behind me.’ While elated with her newfound energy, she dreads the prospect of recurring lows and hopes someone will catch her when she falls. The accompanying music becomes increasingly darker as the woman slides into depression, while bursting with energy during her manic episodes.

This synergy and play between lyrics and music is a constant throughout the song. The gentle melody and sweet singing of Goodnight Kiss is reminiscent of a lullaby. However, as the vocals become haunting, the music louder and the text ever gloomier, it is evident something is wrong. Although PPD, a malady about which few songs exist, is less clearly represented than the other conditions, the incongruency between music and text displayed here is interesting: investigations show that infant-directed singing by mothers with depressive symptoms is less sensitive to their child's emotional needs.

Solitary Shell exemplifies how during development, symptoms related to autism emerge in specific social interactions (‘Never cared much to be held’, ‘Kept to himself most of the time’). Contact with others may be impaired, which may result in feelings of loneliness and difficulty in adulthood. The lyrics talk of a person with a rich inner life, who struggles to reach out: ‘Lost within himself.’ Through the engaging and playful melody and instrumentation, this inner wealth is given shape and form, strengthening the appeal ‘When will he be let out of his solitary shell’ with which the section ends.

Psychopathology is a common theme in metal music. However, few bands manage to capture core symptoms, social context and part of the lived experience in music and text so vividly as Dream Theater. The song closes with a plea for understanding, an end to stigma and effort to help those in need – a call that remains relevant today.