This study protocol proposes an EEG based neurofeedback (EEG-NFB) technique to upregulate the posterior cingulate cortex (PCC) in patients suffering from mild cognitive impairment (MCI) and early Alzheimer's disease (AD).

EEG-NFB has been successfully used as a clinical tool for over 40 years. It is based on electrical activity measured near the surface of the brain using EEG and fed back to the patient within half a second.

MCI is a clinical condition considered as a precursor of AD. NFB appears to be a promising approach to treat MCI, since it has been shown to be able to induce changes in brain plasticity. This research focuses on the PCC, which has been reported to be implicated in MCI, and due to its location (proximity to the surface) accessible by means of EEG- NFB.

A preliminary research in MCI patients, conducted at our lab showed the lower the memory score was at the beginning of the training, the better a subject managed to improve later on. The investigators therefore presume that patients with early Alzheimer's disease, whose cognitive ability is more affected compared to MCI, may benefit from EEG-NFB as well, and maybe to a larger extent compared to MCI.

Cognitive impairment preceding dementia is called mild cognitive impairment (MCI) . Patients with MCI are at high risk for progression to Alzheimer's disease (AD), at a rate of about 12% per year. The amnestic form of MCI is the most common form, and most of the literature on the topic refers to this form of the disorder. Clinical criteria for MCI include:

1. Memory complaint, preferably corroborated by an informant.
2. Objective memory impairment for age and education.
3. Largely intact general cognitive function.
4. Essentially preserved activities of daily living.
5. Not demented

Currently, there is no known cure for MCI or means of stopping or reversing its progression. Patients with Alzheimer's disease were also included in this study , as they are considered by many researchers to be on the same continuum of cognitive decline as patients with MCI which indeed, carry an increased risk for developing Alzheimer's disease.

This study relies the data from a preliminary study conducted in the investigators' lab on patients with MCI, and is meant to further validate our results. In the aforementioned study, participants managed to improve their memory score after 10 training sessions. In addition, a negative correlation between initial memory score and ability to improve was found. It is therefore hypothesized that subjects with AD may benefit as much as subjects with MCI and perhaps even to a larger extent.

Neurofeedback (NFB) is a treatment method based on learning with operant conditioning, in which a feedback (or a reward) is given in proportion with the desired physiological activity in order to improve cognition and/or behavior. This research will focus on using electrical activity measured with EEG as physiological activity to be influenced.

EEG-NFB has been successfully used as a clinical tool for over 40 years treating various disorders from epilepsy, attention deficit hyperactivity disorder (ADHD), stroke to PTSD

Electroencephalography (EEG) equipment is used to measure the electrical activity representing the neuronal activity of different parts of the brain. During the treatment, electrode(s) are placed in predetermined location. Audio and visual rewards are given when the activity is measured to be within the desired frequency range.

Since NFB has been shown to be able to induce changes in the brain plasticity, it appears to be a promising approach to treat MCI. Few studies have shown improvement in cognition of normal elderly with subjective complains of memory decline. To the best of our knowledge, this study is the first to address memory decline in MCI using EEG-based neurofeedback protocol, enhancing the individual upper alpha and peak alpha frequency.

This study will include 30 participants which will be randomly assigned into experimental or sham groups. The former will include training the individual upper alpha, while the latter will include feedback over static electrical activity of a disconnected electrode.

each participant will be trained for a total of 10 sessions over a period of 5 weeks (2 training sessions per week), lasting approx. 1 hour. Cognitive evaluations will take place at baseline, after the training sessions have ended and at 30 days after the last session.

Inclusion Criteria:

• Diagnosis of either mild cognitive impairment or mild Alzheimer's disease
• Age > 50

Exclusion Criteria:

• Active neurological disorder
• Any axis 1 type disorder