The aim of this study is to investigate the effect of these two different intravenous infusion techniques [manuel controlled infusion (MCI) and Target controlled Infusion( TCI)] on POCD. To assess POCD, the Mini Mental State Examination (MMSE ) and the Montreal Cognitive Assessment (MoCA ) will be used. MoCA and MMSE have high sensitivity and specificity for identifying patients with mild cognitive impairment who perform within the normal range. In a study by Meng et al., comparing target-controlled infusion and manual infusion of propofol anesthesia during electroconvulsive therapy, the randomized, controlled trial showed no significant difference in postelectroconvulsive therapy changes in MoCA scores in either group; however, they reported improvement in MoCA scores after 6 electroconvulsive therapy treatments in the MCI group, while deterioration occurred in the TCI group. Researchers found no studies investigating the effects of both infusion methods in spinal surgery and their impact on cognitive function, and they planned to evaluate the effects of the groups in their study.

Inclusion Criteria:

• Turkish language proficiency,
• age (18-65 years),
• American Society of Anesthesiologists (ASA) I-III score,
• elective spinal surgery.

Exclusion Criteria:

• - refusal to participate
• central nervous system disorders,
• use of antidepressants or antipsychotic medications,
• alcohol or drug use,
• illiteracy.