The study investigated the leakage potential of different voice and speech using isolation and masking design. Speech samples taken from an earlier experiment were used in which 15 female students of nursing dissimulated negative affect produced by an unpleasant mivie or told the truth about positive affect following a pleasant movie. Several groups of judges rated these speech samples in five conditions: (1) forward or clear (2) electronic filtering, (3) random spliting, (4) backwards, (5) pitch inversion, (6) tone silence sequences. The results show that vocal cues do indeed curry leakage information and that, as reflected in the differences among the conditions masking different types of cues respectively, voice quality cues may be centrally implicated. In addition, gender differences in decoding ability are discussed.