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The advent of real-time neurofeedback techniques has allowed us to begin to map the controllability of sensory and cognitive and, more recently, affective centers in the brain. The subgenual anterior cingulate cortex (sACC) is thought to be involved in generation of affective states and has been implicated in psychopathology. In this study, we examined whether individuals could use real-time fMRI neurofeedback to modulate sACC activity. Following a localizer task used to identify an sACC region of interest, an experimental group of eight women participated in four scans: (1) a pretraining scan in which they were asked to decrease activity in the sACC without neurofeedback; (2) two training scans in which sACC neurofeedback was presented along with instructions to decrease sACC activity; and (3) a neurofeedback-free post-training scan. An additional nine women in a yoked feedback control group saw sACC activity from the participants in the experimental group. Activity in the sACC was significantly reduced during neurofeedback training in the experimental group, but not in the control group. This training effect in the experimental group, however, did not generalize to the neurofeedback-free post-training scan. A psychophysiological interaction analysis showed decreased correlation in the experimental group relative to the sham control group between activity in the sACC and the posterior cingulate cortex during neurofeedback training relative to neurofeedback-free scans. The finding that individuals can down-modulate the sACC shows that a primary emotion center in which functional abnormality has been strongly implicated in affective disorders can be controlled with the aid of neurofeedback.

Johnson, R. F. (2010). Breaking family ties: taxon sampling and molecular phylogeny of chromodorid nudibranchs (Mollusca, Gastropoda). —Zoologica Scripta, 40, 137–157. Although researchers have debated the monophyly of the diverse chromodorid nudibranchs (Chromodorididae) for over 100 years, the monophyly of this family has not been properly tested. Recent morphological and molecular phylogenetic studies have added to the debate, but have not used appropriate methods to resolve this issue. I investigate how outgroup choice and taxon sampling influences tree topology and in turn the recovery of chromodorid monophyly. As a demonstration of these potential methodological problems, I then present phylogenies resulting from different taxon-sampling schemes using the same molecular data. Taxon sampling has a strong influence on the resulting phylogenies. With comprehensive taxon sampling and outgroup selection, Cadlina is not a member of the Chromodorididae. The chromodorid nudibranchs without Cadlina are monophyletic and possibly sister to the Actinocyclidae. Additionally, I found, for the first time, support for most current family groupings in the Doridoidea. I propose a new classification in which Cadlina is not considered a member of the Chromodorididae. Instead, I resurrect the family name Cadlinidae to include the genera Cadlina and Aldisa.