Traditionally, memory impairments in the elderly population are treated using cholinesterase inhibitors, although impairments remain after treatment. Dopamine (DA) is also involved in cognition and is especially of interest in healthy ageing because of the role in processing speed and cognitive control. To what extent dopamine treatment improves memory and attention in older impaired individuals is unknown. However, such an effect is conceivable because of the close relationship between memory and attention in aging and since improved processing speed and cognitive control may lead to improved memory.

The investigators aim to examine, in the impaired older population, whether a treatment using methylphenidate, a DA re-uptake inhibitor that enhances DA, improves attention and memory. The study will be conducted according to a cross-sectional, double-blind, placebo-controlled, 2-way cross-over design. 20 male and female patients with Mild Cognitive Impairment (MCI), amnestic type, aged above 60 years of age; 20 male and female patients with MCI, non-amnestic type, will be recruited from the Orbis Medical Centre. Participants will be treated once with 20 mg methylphenidate (MPH) and once with placebo. All medications will be administered orally with a capsule. The treatment order will be established by counterbalancing.

Inclusion Criteria:

• The participant has been diagnosed with Mild Cognitive Impairment, either of the amnestic or the non-amnestic type.
• In the opinion of the investigator, the participant is capable of understanding and complying with protocol requirements.
• The participant signs and dates a written informed consent form.
• The volunteer is male or female.
• The participant is aged 60 to 80 years, inclusive, at the time of informed consent.
• The participant has a body mass index of 18.5-30, inclusive, at medical screening.
• The volunteer is healthy, i.e. absence of all exclusion criteria and has normal static binocular acuity (corrected or uncorrected) as well as normal hearing (using a whisper test during medical screening).

Exclusion Criteria:

• The subject has uncontrolled, clinically significant neurologic, cardiovascular, pulmonary, hepatic, renal, metabolic, gastrointestinal, or endocrine disease or other abnormality which may impact the ability of the subject to participate or potentially confound the study results.
• The volunteer has uncontrolled existing major psychiatric symptoms.
• The subject has uncontrolled hypertension.
• The volunteer has hyperthyroidism.
• The participant has known hypersensitivity to any component of the formulation of MPH or related compounds.
• The participant has glaucoma.
• The subject has a history of drug abuse (defined as any illicit drug use) or a history of alcohol abuse within 1 year prior to the first visit or is unwilling to agree to abstrain from alcohol from 24 hours prior to each test day and/or drugs throughout the study.
• The participant has any sensory or motor deficits which could reasonably be expected to affect test performance.