MILimbEEG: An EEG Signals Dataset based on Upper and Lower Limb Task During the Execution of Motor and Motorimagery Tasks

In this work, an experimental methodology for the acquisition of EEG signals from volunteer subjects was developed. The volunteers are colleagues and research fellows from ESPOL and patients of the Hospital Luis Vernaza for participating as test subjects. This dataset consists of over 8680 four-second EEG recordings obtained from 60 volunteers.

Equipment:
We use the OpenBCI Cyton + Daisy (www.openbci.com) Biosensing Board for EEG signal recording. The OpenBCI equipment has an active bandpass filter in the 5 to 50Hz range, additionally, a notch filter at 60Hz. This non-invasive device operates within a sampling frequency of 125Hz and has 16 dry electrodes with two ground references, distributed in the international 10-10 system. All 16 EEG electrodes were recorded in monopolar configuration, in which the potential of each electrode is compared with a neutral electrode located in both lobes of the ears.

Data Description:
Each recording was recorded in a CSV file format, the values of each electrode are in microvolts (uV). In total, each subject generates 124 CSV files in each experiment (run). Some subjects perform two experiments, one executing the motor tasks and the other imagining doing them. The tasks are described below:
- Recording a Baseline with Eyes Open (BEO) without any task command: only once at the beginning of each run.
- Closing Left Hand (CLH): five times per run.
- Closing Right Hand (CRH): five times per run.
- Dorsal flexion of Left Foot (DLF): five times per run.
- Plantar flexion of Left Foot (PLF): five times per run.
- Dorsal flexion of Right Foot (DRF): five times per run.
- Plantar flexion of Right Foot (PRF): five times per run.
- Resting in between tasks (Rest): after each task, in total 31 files.

CSV file encoding:
- Subject ID: Assigned ID to each test subject in order to hide their identity. e.g. Sx, such that x can be any number from 1 to 60.
- Repetition number: The participants may perform more than one repetition of the experiment. ExaOnly one subject volunteered to perform up to 4 repetitions. e.g. Rx, such that x can be any repetition number between 1 and 4.
- Motor or Motor Imagery Activity: For each repetition, participants are asked to perform first the motor tasks (M) and then the motor imagery tasks (I). & Mx and Ix, where x is the Label of the task performed.
- Label: Identifier of the performed task, where 1 is for BEO, 2 for CLH, 3 for CRH, 4 for DLF, 5 for PLF, 6 for DRF, 7 for PRF and finally 8 for Rest. e.g. M2 represents the CLH Motor task.
- Task repetition number: Ordinal number of the task repetition. Tasks are presented randomly up to 5 times per run. e.g. S24R1I6_5 is from subject 24, repetition 1, DRF Imagery task. Finally, the number five at the end represents the fifth task repetition in the record.

Additionally, this dataset includes the file "Test_Subject_Annotations.csv", with the demographic information of each of the 60 volunteers, respecting the confidentiality of each individual.