Table 1.
Complete list of predictive basic symptoms illustrated by typical statements from patients.
| SPI-A Item No. | Basic symptom name | Typical statementa |
|---|---|---|
| B1 | Inability to divide attentionb | I can’t focus on driving and listening to the radio simultaneously. I have to concentrate on one or the other. |
| C2 | Thought interferencesb, c | When I try to focus, inappropriate words come to my mind and distract me.d |
| C3 | Thought blockagesb,c | Whenever I want to think about something, I cannot think. No thoughts come; my head remains empty. |
| C4 | Disturbance of receptive speechb,c | It happens that I suddenly can no longer grasp the most straightforward words.a |
| C5 | Disturbance of expressive speechb | Often speaking doesn’t work correctly, although I have the words I want to say in my mind. |
| D3 | Thought pressureb,c | There are just too many thoughts. It’s like ten different pieces of music playing at the same time, and you cannot tell one from the other. |
| D4 | Unstable ideas of reference, “subject-centrism”b,c | When strangers are laughing in the street, it strikes me as they are laughing at me. Then I quickly discard this thought. |
| When I was listening to the radio, the idea that the lyrics had some special meaning intended for me suddenly popped up in my head. Of course, I knew straight away that it was just my imagination, a kind of weird thing. I did not have to think twice about it to know that. | ||
| O1 | Thought perseverationc | When I am having a conversation, I have to think about recent conversations about people and things that I don’t want to think of. |
| O2 | Decreased ability to discriminate between ideas and perception, fantasy and true memoriesc | Occasionally, when I see something, I’m unsure if it is real or only in my imagination. |
| I thought of my grandparents. Then a weird thing happened: I couldn’t remember if I knew my grandparents properly, if they were real or if they were just in my imagination. Did I know them, or had I made them up? | ||
| O3 | Disturbances of abstract thinkingb | I must stick to the facts. It is difficult for me to understand metaphors. |
| O4 (ten subitems) | Other visual perception disturbancesc | Sometimes things looked distorted or warped. |
| Occasionally, everything looked like it had moved far away. | ||
| Often, I don’t grasp the whole picture; then, I see only parts, e.g., faces or objects. | ||
| O5 (two subitems) | Other acoustic perception disturbancesc | I often hear undefined noises such as knocking, hissing, or buzzing. |
| O7 | Captivation of attention by details of the visual fieldb | I cannot just look through a window without cracks, smudges, etc., attracting my attention to such an extent that it disturbs me. |
| O8 | Derealizationc | I had a feeling of unreality. As if everything was an imitation of reality - similar to a staged theater set. |
aThe typical statements in Table 1 are taken literally or in a modified form from the Bonn Scale for the Assessment of Basic Symptoms (BSABS) and the Schizophrenia Proneness Instrument, Adult Version (SPI-A) manuals, as well as from the article of Eisner et al., 2017 (Eisner et al. 2018), and transcribed diagnostic interviews from the first author (HM) within the CHR service at the university hospital of Cologne, Germany.
bCOGDIS.
cCOPER.
dAffectively neutral words and other cognitions without a negative connotation.