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source localization, but with a significant exception in that the fish adopted a constant 0° orientation angle with respect to the local particle motion vector and not an
arbitrary orientation angle that was constantly maintained. Zeddies et al. (2012)
conclude that for a dipole source, midshipman fish do not appear to “know” where
the source is, but it can use the acoustic cues of local particle motion vectors as a
guide to determine the direction to the sound source. This conclusion, however, is
not entirely justified since, as can be seen in Fig. 6, five of the females swam directly
toward the source and apparently did “know” where it was. How the fish could
know where the source was in this situation is discussed in Sect. 4.
2.8 Role of the Swim Bladder and Lateral Line in Near-Field
Sound Source Localization
Recently Coffin et al. (2014) investigated the roles of the swim bladder and the lateral line system in sound source localization behavior in the plainfin midshipman.
In the first set of experiments, gravid females underwent surgical deflation of the
swim bladder soon after collection and then were tested later that night in a monopolar sound source localization task. Females with nominally “deflated” swim bladders exhibited similar phonotaxic responses to that of sham-deflated controls
Fig. 7 Phonotaxic response pathways of gravid female midshipman that underwent swim bladder
deflation surgery. Response pathways of females with sham-deflated swim bladders (left plot) that
exhibited positive (green circle) phonotaxis and negative (red circle) responses to the simulated
advertisement call stimulus. Response pathways of females with deflated and re-inflated swim
bladders (right plot) that exhibited positive phonotaxis with either deflated (green circle) or reinflated (blue triangle) swim bladders and negative responses with either deflated (red square) or
re-inflated (orange diamond) swim bladders. The axes are the distance from the center of the tank
in cm where the monopole J9 speaker (black square) was located and the dotted line represents the
position of the opaque screen. Adapted from Coffin et al. (2014)
J.A. Sisneros and P.H. Rogers
source localization, but with a significant exception in that the fish adopted a constant 0° orientation angle with respect to the local particle motion vector and not an
arbitrary orientation angle that was constantly maintained. Zeddies et al. (2012)
conclude that for a dipole source, midshipman fish do not appear to “know” where
the source is, but it can use the acoustic cues of local particle motion vectors as a
guide to determine the direction to the sound source. This conclusion, however, is
not entirely justified since, as can be seen in Fig. 6, five of the females swam directly
toward the source and apparently did “know” where it was. How the fish could
know where the source was in this situation is discussed in Sect. 4.
2.8 Role of the Swim Bladder and Lateral Line in Near-Field
Sound Source Localization
Recently Coffin et al. (2014) investigated the roles of the swim bladder and the lateral line system in sound source localization behavior in the plainfin midshipman.
In the first set of experiments, gravid females underwent surgical deflation of the
swim bladder soon after collection and then were tested later that night in a monopolar sound source localization task. Females with nominally “deflated” swim bladders exhibited similar phonotaxic responses to that of sham-deflated controls
Fig. 7 Phonotaxic response pathways of gravid female midshipman that underwent swim bladder
deflation surgery. Response pathways of females with sham-deflated swim bladders (left plot) that
exhibited positive (green circle) phonotaxis and negative (red circle) responses to the simulated
advertisement call stimulus. Response pathways of females with deflated and re-inflated swim
bladders (right plot) that exhibited positive phonotaxis with either deflated (green circle) or reinflated (blue triangle) swim bladders and negative responses with either deflated (red square) or
re-inflated (orange diamond) swim bladders. The axes are the distance from the center of the tank
in cm where the monopole J9 speaker (black square) was located and the dotted line represents the
position of the opaque screen. Adapted from Coffin et al. (2014)
J.A. Sisneros and P.H. Rogers