ORDER After finding him guilty of selling drugs within the prison, a conduct adjustment board (“CAB”) sanctioned Indiana prisoner Willie Ward with the loss of phone privileges for two months, written reprimands, and two years’ disciplinary segregation. Ward challenged the CAB sanctions under 28 U.S.C. § 2254, and the district court denied his petition. Because the CAB sanctions affected the severity rather than the duration of his custody, Ward’s petition was improperly brought under § 2254. See Montgomery v. Anderson, 262 F.3d 641, 643-44 (7th Cir.2001); see also Moran v.
Sondalle, 218 F.3d 647, 650-51 (7th Cir.2000) (state prisoners challenging administrative segregation must use 42 U.S.C. § 1983, not § 2254); Sylvester v. Hanks, 140 F.3d 713, 714 (7th Cir.1998) (expressing doubt that challenge to 3 years disciplinary segregation should proceed under § 2254). We note that Ward might have a valid § 1983 claim if, as he claims, he suffered psychological harm from being held for weeks in a cold, perpetually lighted cell. See, e.g., Ferguson v. Cape Girardeau County, 88 F.3d 647, 650 (8th Cir.1996) (noting detrimental effects of constant illumination); Keenan v.
Hall, 83 F.3d 1083, 1090-91 (9th Cir.1996) (reversing grant of
summary judgment on Eighth Amendment claim when inmate subjected to bright light 24-hours per day alleged grave sleeping problems and psychological harm). AFFIRMED.