It seems to be very unlikely that brain cysts (that might affect cognition) can form in immunocompetent people — a pathological study of AIDS patients showed cysts in ~20%; background seropositivity in France (where the study was conducted) is ~40%.

Conclusion by the authors: the amount of toxoplasmic agents appeared to be related to the degree of deterioration of the immune status.

> Neuropathological studies in the brains of AIDS patients with opportunistic diseases: https://pubmed.ncbi.nlm.nih.gov/8518200/