Yellowtail damselfish Chrysiptera parasema can associate predation risk with the acoustic call of a heterospecific damselfish following pairing with conspecific alarm cues.

The ability to detect and respond to the presence of predation risk is under intense selection, especially for small-bodied fishes. Damselfishes (Pomacentridae) use auditory vocalizations during inter- and intrasexual interactions, but it is not known if they can use vocalizations in the context of predator-prey interactions. Here, we test if yellowtail damselfish, Chrysiptera parasema, can learn to associate the territorial vocalization of heterospecific humbug damselfish Dascyllus aruanus with predation risk.

Association of predation risk with a heterospecific vocalization by an anabantoid fish.

Honey gouramis (Trichogaster chuna) received chemical alarm cues derived from conspecific epidermal tissue and, simultaneously, the vocalization produced by a heterospecific gourami species, the sparkling pygmy gourami (Trichopsis pumila). Control trials paired water with the vocalization. In trials that received alarm cues, honey gouramis significantly increased activity relative to control trials that received water, suggesting an attempt to flee and search for refuge.

A pilot study of functional magnetic resonance imaging brain correlates of deception in healthy young men.

We hypothesized that specific brain regions would activate during deception, and these areas would correlate with changes in electrodermal activity (EDA). Eight men were asked to find money hidden under various objects. While functional MRI images were acquired and EDA was recorded, the subjects gave both truthful and deceptive answers regarding the money's location.

BOLD-fMRI response vs. transcranial magnetic stimulation (TMS) pulse-train length: testing for linearity.

Purpose: To measure motor and auditory cortex blood oxygenation level-dependent (BOLD) functional magnetic resonance imaging (fMRI) response to impulse-like transcranial magnetic stimulation (TMS) pulses as a function of train length.

Materials And Methods: Interleaved with fMRI at 1.5 T, TMS pulses 0.

Are there really no evolutionarily stable strategies in the iterated prisoner's dilemma?

The evolutionary form of the iterated prisoner's dilemma (IPD) is a repeated game where players strategically choose whether to cooperate with or exploit opponents and reproduce in proportion to game success. It has been widely used to study the evolution of cooperation among selfish agents. In the past 15 years, researchers proved over a series of papers that there is no evolutionarily stable strategy (ESS) in the IPD when players maintain long-term relationships.