The evolution of the language faculty: clarifications and implications

In this response to Pinker and Jackendoff's critique, we extend our previous framework for discussion of language evolution, clarifying certain distinctions and elaborating on a number of points. In the first half of the paper, we reiterate that profitable research into the biology and evolution of language requires fractionation of "language" into component mechanisms and interfaces, a non-trivial endeavor whose results are unlikely to map onto traditional disciplinary boundaries. Our terminological distinction between FLN and FLB is intended to help clarify misunderstandings and aid interdisciplinary rapprochement. By blurring this distinction, Pinker and Jackendoff mischaracterize our hypothesis 3 which concerns only FLN, not "language" as a whole. Many of their arguments and examples are thus irrelevant to this hypothesis. Their critique of the minimalist program is for the most part equally irrelevant, because very few of the arguments in our original paper were tied to this program; in an online appendix we detail the deep inaccuracies in their characterization of this program. Concerning evolution, we believe that Pinker and Jackendoff's emphasis on the past adaptive history of the language faculty is misplaced. Such questions are unlikely to be resolved empirically due to a lack of relevant data, and invite speculation rather than research. Preoccupation with the issue has retarded progress in the field by diverting research away from empirical questions, many of which can be addressed with comparative data. Moreover, offering an adaptive hypothesis as an alternative to our hypothesis concerning mechanisms is a logical error, as questions of function are independent of those concerning mechanism. The second half of our paper consists of a detailed response to the specific data discussed by Pinker and Jackendoff. Although many of their examples are irrelevant to our original paper and arguments, we find several areas of substantive disagreement that could be resolved by future empirical research. We conclude that progress in understanding the evolution of language will require much more empirical research, grounded in modern comparative biology, more interdisciplinary collaboration, and much less of the adaptive storytelling and phylogenetic speculation that has traditionally characterized the field.     

Depth perception: cuttlefish (Sepia officinalis) respond to visual texture density gradients

Studies concerning the perceptual processes of animals are not only interesting, but are fundamental to the understanding of other developments in information processing among non-humans. Carefully used visual illusions have been proven to be an informative tool for understanding visual perception. In this behavioral study, we demonstrate that cuttlefish are responsive to visual cues involving texture gradients. Specifically, 12 out of 14 animals avoided swimming over a solid surface with a gradient picture that to humans resembles an illusionary crevasse, while only 5 out of 14 avoided a non-illusionary texture. Since texture gradients are well-known cues for depth perception in vertebrates, we suggest that these cephalopods were responding to the depth illusion created by the texture density gradient. Density gradients and relative densities are key features in distance perception in vertebrates. Our results suggest that they are fundamental features of vision in general, appearing also in cephalopods.     

Behavioral evidence for two distinct memory systems in rats

Animal Cognition - Serial reaction time tasks, in which subjects have to match a target to a cue, are used to explore whether non-human animals have multiple memory systems. Predictable...     

Ego development in perspective: Structural stage,functional phase,and cultural age-period models

Ego development is emerging as one of the more important areas of research in developmental psychology. This paper presents a structural stage approach to ego development and distinguishes it from two other models of ego development, which are termed functional phases and cultural ages. Two subtypes are also delineated within the structural stage approach—a monodomain and a multisubdomain—and the latter is argued for. These concepts are then illustrated through an analysis of four prominent ego development theories—those of Robert Selman, Robert Kegan, Jane Loevinger, and Erik Erikson. The important similarities and critical differences of the theories are clarified, which enables the authors to present a summary integration.     

Gender differences in implicit exposure to cyber-pornography

ABSTRACT

Cyber-pornography consumption has become a widespread behavioral habit, with potential diverse outcomes for the user. Previous studies have repeatedly found that males are exposed to cyber-pornography more than females, when they are asked about it explicitly. However, perceived social acceptance of cyber-pornography consumption may dramatically bias such explicit reports. The current study aimed at better understanding gender differences in exposure to cyber-pornography using both explicit self-report measures and a new measure developed to examine exposure to cyber-pornography indirectly. The findings demonstrated gender differences in exposure to cyber-pornography in both measures. Women tended to understate the extent of their exposure. Interestingly, men showed the opposite tendency. Lastly, perceived social acceptance mediated the relationship between gender and explicit report bias. We discuss the conclusions of the current study in relation to previous theories and findings, as well as the importance of using indirect measures to study socially controversial topics such as cyber-pornography.