BrainAccess CAP

The BrainAccess CAP is a versatile EEG cap that is available in different sizes and comes with dry-contact, shape-conforming gold-plated electrodes.

The BrainAccess CAP is designed to work with BrainAccess electroencephalographs and can be purchased as part of BrainAccess kits.


3 different sizes. The cap is available in 3 different sizes: L, M, and S to fit different adult head sizes and shapes.


Head circumference

Typical user


54 – 59 cm



50 – 55 cm

male, female


48 – 52 cm

female, children

Number of electrodes. The total number of electrodes provided with the cap varies depending on the purchased kit. Standard Kit comes with an 8-electrode cap with additional reference and bias electrodes while Extended and Extended+ Kits come with 16 and 32-electrode caps respectively.

Dry-contact electrodes. The cap comes with dry-contact electrodes. The electrodes feature spring-loaded spikes that enable the electrode to conform to the curvature of the head resulting in a more comfortable wear when compared to standard dry-contact electrodes.

Dry-contact pad electrodes. Electrodes with golden pads are provided for the positions without hair, i.e., the forehead. Typically, a pad electrode at the Fp1 position is used as a reference electrode and an electrode at Fp2 as a bias electrode in BrainAccess setups. These electrodes generally have good contact which is essential for reference electrodes as it affects the measurements on all the channels. It is recommended to re-reference to average reference or other electrode in software if needed.

34 electrode positions. The cap provides 34 positions where the electrodes can be placed using an easy-to-use clipping mechanism. The positions follow the standard 10-20 system and are conveniently labeled on the cap.

BrainAccess CAP - BrainAccess

Electrode positions for BrainAcces CAP setups in a 10-20 system notation. Fp1 is typically used for the reference electrode and Fp2 for the bias electrode. Highlighted (green) electrode positions are for the default 16-electrode setup (BrainAccess Extended Kit), but users can place electrodes in different positions if they prefer. 32-electrode setup (BrainAccess Extended+ Kit) fills all the available positions.

Single connector. 16 and 32-electrode caps come with a single connector to connect with BrainAccess MIDI or BrainAccess MAXI electroencephalographs. Therefore, MIDI/MAXI devices can be quickly attached/detached to different size caps for taking the measurements. The connectors on MIDI/MAXI devices are compatible, so, for example, the 16-electrode cap could be used with MAXI devices as well. In an 8-electrode cap, each electrode has to be connected individually with micro-coax cables to the MINI device.

Ultra small cables. The CAP is equipped with ultra-miniature coaxial cables that not only ensure shielding from the noise but are also thin and flexible to ensure comfort.

Velcro tape attachment. The cap features a piece of velcro tape below the back side of the cap. BrainAccess electroencephalograph should be attached there.

Machine washable. For hygienic purposes, the cap can be machine-washed using a delicate wash cycle. Make sure to remove the electrodes and cables from the cap before washing. The electrodes can be cleaned with standard disinfectant liquids/sprays and non-abrasive wipes.



size (head circumference)

L (54-59 cm)

M (50-55 cm)

S (48-52 cm)



number of holes for electrode attachments








20 mm

number of spikes

12 x spring-loaded

number of pads (for forehead)

5 x 6mm diameter

input connector

ECG 4mm snap connector (male)



ultra-miniature RF coaxial


different lengths for different electrode positions

electrode connector

ECG 4mm snap connector (female)

electroencephalograph connector

Harting Harflex 2 x 20 1.27mm pitch (male)

electroencephalograph connector (8-electrode cap)

ultra-mini RF coaxial connectors