Figure 2

Experimental paradigm. The experiment was divided into three parts. First, participants underwent six hours of training, followed by interim testing of face identification and detection of changes to facial features (1b). The strip-method was used in this first part: each face was divided into three horizontal strips representing the upper, middle, and lower parts of the face (1a). To teach participants the composition of face parts and how to tune their hearing to perceive multiple tones at the same time, they were trained to perceived details within each strip. Following completion of this stage, participants were able to integrate their knowledge and perceive the complete face soundscapes. Second, participants underwent additional 6 h of whole-face training (2a). They subsequently took part in several tasks designed to test face identification, including the identification of learned faces in the untrained, inverted orientation (2b). Third, participants underwent an additional pre-post experiment, in which they quickly learned a new cohort of six faces and were tested on face identification before and after two hours of training (3a–3c).