This project includes data files from a single experiment. The experiment aimed to investigate whether people can be trained to discriminate the eye of origin of a monocular stimulus. The three data files are from three separate blocks of experimentation: baseline, training, and test. We measured the accuracy of eye of origin judgments before and after the training period. Using continuous flash suppression, we recorded suppression times (indicative of monocular signal strength), eye of origin judgments and related confidence ratings. Then, the participants completed a training block in which they were instructed to orient their attention to the cued eye. After the training, we repeated the eye of origin discrimination task. The three data files starting with "control" are from three separate blocks performed by the control group of participants: baseline, middle, and test. Middle block here was the same as the baseline and test blocks. . The following participants were excluded from further analysis: S1, S2 (confidence ratings missing) S6, S28, S42 (image dissociation during cfs) S13, S31, S37 (long suppression times, > 10sec) S3, S45, S56 (high number of incorrect target localization trials) . Each file is organized in columns for variables and rows for each trial. **Variables (columns)** **eyeoforigin:** Which eye the grating is presented to (1: left 2: right) **localisation:** The location of the grating (1: up 2: down) **cue:** Which eye is cued (1: left 2: right) **supT:** Suppression time (time from mask onset to participant localisation response) **contrast:** Contrast of the grating at the time of respose (up to 0.50) **response:** Participant target localisation response (1: up 2: down) **response_eye:** Participant eye of origin response (1: left 2: right) **RTeye:** Reaction time for the eye of origin response (time from question onset to response) **confidence:** Participant confidence rating (1: chance 2: moderate 3: high) **RTconfidence:** Reaction time for the confidence rating (time from question onset to response) **Participant:** Participant ID **Trial:** Trial number per participant (each block contains 100 trials) . **Abstract** Helmholtz asked whether one could discriminate which eye is the origin of one’s perception merely based on the retinal signals. Studies to date showed that participants’ ability to tell the eye-of-origin of their perception most likely depends on contextual cues. Nevertheless, it has been shown that exogenous attention can enhance performance for monocularly presented stimuli. We questioned whether adults can be trained to discriminate the eye-of-origin of their perceptions and if this ability is dependent on the strength of the monocular channels. We used attentional feed-forward training to improve the subject’s eye of origin discrimination performance with voluntary attention. During training, participants received a binocular cue to inform them of the eye of origin of an upcoming target. Using CFS, we also measured the signal strength of the monocular targets to see any possible modulations related to the cues. We collected confidence ratings from the participants about their eye-of-origin judgments to study in further detail whether metacognition has access to this information. Our results show that, even though voluntary attention did not alter the strength of the monocular channels, eye-of-origin discrimination performance improved following the training. A similar pattern was observed for metacognition, with confidence ratings showing improved calibration to objective performance. The results from the feedforward attentional training and the improvement in metacognitive ability point towards a high-level decisional mechanism being responsible for the eye-of-origin judgment. We propose that this high-level process is informed by subtle sensory cues such as the differences in luminance or contrast in the two monocular channels.