Probabilistic functionalism: A conception of research method.

Describes the accepted psychological research paradigm and discusses its inherent limitations. The author outlines an alternative paradigm that is adequate to the task of understanding organism–environment relationships. This alternative paradigm is formulated in terms of E. Brunswik's (1952) lens model. The author then develops some theoretical implications of the lens model. These include the importance of situational sampling, the nature and focus of analytic statistical procedures, and the characteristics of a molar functional approach as contrasted with those of a molecular reductionistic one. The author discusses the essentials of representative design and suggests the conception of construct validity as developed in psychometric theory as a general scheme adequate to guide theory construction. (62 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Left-handedness.

Reviews the phenomenon of left-handedness from prehistoric man through contemporary studies of lateralization of cerebral function. The following conclusions seem warranted: Handedness is most appropriately regarded as a continuum ranging from strong right-handedness across mixed-handedness to strong left-handedness. Left-handedness, ranging from moderate through strongly left-handed, is found in approximately 10% of the population. Evidence for a genetic basis of handedness remains positive, but with no direct link established. There is remarkably little evidence for any association of left-handedness with deficit. The familial left-handed show greater recovery of functioning following unilateral cerebral insult than do nonfamilial right-handed and nonfamilial left-handed. Both behavioral and clinical lesion studies indicate systematic differences in lateralization of cerebral function between the right- and left-handed and the familial and nonfamilial left-handed. A classification of handedness and lateralization of cerebral function is suggested. The possibilities exist that bilaterality of cerebral functioning either is stable in the human race or is changing at an extremely slow rate. (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Field studies of habituation: V. Evidence for a two-factor, dual-process system.

Recorded song was played in the field to mated pairs of white-crowned sparrows that were in breeding condition, and an extensive sample of the behaviors elicited was recorded. The patterning and type of stimulus varied for 4 groups: (1) 6 Ss received the same song for 8 trial blocks all on 1 day, (2) 4 Ss received a different song for 8 trial blocks all on 1 day, (3) 5 Ss received the same song for 8 trial blocks each conducted on a different day, and (4) 5 Ss received a different song on each of 8 days. The 1-day groups, in general, were more responsive than the 8-day groups, and those played a different song in each trial block were more responsive than those groups that were played the same song. The 8-day same song group had the greatest number of significant response decrements. Results support a theory employing 2 independent processes—habituation and sensitization—each of which is influenced by 2 factors—relative permanence and stimulus specificity. The substance of this revised 2-process theory is developed. (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Field studies of habituation: II. Effect of massed stimulus presentation.

Studied the nature of habituation to massed natural signals in a bird's normal environment. In 2 field experiments, recorded song was played to 27 mated pairs of the sedentary subspecies of the wild white-crowned sparrow (Zonotrichia leucophrys nutalli). Continuous recordings of all the behaviors elicited were made. Patterns of response depended on whether the female was brooding eggs, feeding nestlings, or feeding fledglings and on the behavior under consideration. Massing of songs played to pairs did not result in an increased response decrement. Successive tests of the same pairs in different breeding conditions resulted in a decreased responsiveness on the successive tests. Almost no spontaneous recovery occurred over periods ranging from 60 min to 15 days. The ineffectiveness of the additional trials are attributed to a general sensitization component that masks habituation. Data are discussed in relation to the 2-process model of habituation of R. F. Thompson et al (1973). (10 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

An empirical study of moral intuitions: Toward an evolutionary ethics.

This study of moral intuitions used a questionnaire containing 2 moral dilemmas that were administered to university students. The dilemmas probed the underlying dimensions involved in moral intuitions. The results of both group- and individual-level analyses suggested that the most important dimensions were Speciesism, Abhorrent Political Philosophy (Nazism), and Inclusive Fitness, followed by Social Contract and Number of Individuals. The dimensions of Action–Inaction, Elite, and Endangered Species had significant but weak influences. The results are interpreted within an evolutionary framework and represent progress toward developing an understanding of the is on which it is possible to base the ought (a consideration of the moral imperatives when a legitimate conflict of interest exists between different living beings). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Field studies of habituation: IV. Sensitization as a function of the distribution and novelty of song playback to white-crowned sparrows.

Recorded song was played in the field to mated pairs of white-crowned sparrows that were in breeding condition, and an extensive sample of the behaviors elicited was recorded. An attempt was made to manipulate the level of responding and the amount of habituation by varying the pattern of song presentations and the novelty of the songs. No differences in rates of habituation were obtained, but the attempt to manipulate levels of responding was successful. For the males, greater spacing of the playback trials resulted in lower response levels, whereas changing the song type on each trial resulted in higher response levels. Results are discussed in terms of their meaning for habituation theory and their possible significance to the economy of the birds in adjusting to their environment. (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Field studies of habituation: I. Effect of reproductive condition, number of trials, and different delay intervals on responses of the white-crowned sparrow.

Studied the nature of habituation to natural signals in a bird's normal environment. In 22 experiments, recorded song was played to 22 mated pairs of wild white-crowned sparrows of the sedentary Nuttalli subspecies (Zonotrichia leucophrys nutalli). Continuous recordings of all the behavior elicited were made. Behaviors were analyzed during playback periods and silent periods following playback. The pattern of responses depends both on whether the female has eggs, nestlings, or fledglings and on the behavior under consideration. These patterns can be understood in the context of the behavior appropriate during each of the different stages of the reproductive cycle. Doubling the number of playback trials did not result in a greater response decrement. Spontaneous recovery did not occur after periods of 0, 60, or 300+ min. Presentation of a novel song resulted in increased levels of response. The problem of operationally distinguishing between learning and habituation is discussed. (32 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Factors influencing song development in the white-crowned sparrow (Zonotrichia leucophrys).

Nestling white-crowned sparrows (Z. l. nuttalli) were handreared in sound-isolation chambers under a variety of conditions. The songs of 9 total isolates were compared with songs of 2 Ss tutored with song, and the number of inputs sufficient for an S to produce a normal song was explored. The flexibility of the song-learning system was investigated with a range of tape-recorded tutor songs: alien dialects, alien subspecies, alien species, alternating alien dialects, and an aberrant song. Adult songs were obtained for 40 males and 7 testosterone-injected females. All of the tutor songs could be learned; some Ss learned elements of an alien species' song. Ss tutored with 2 songs copied 1 or the other, were bilingual, or sang a hybrid of the 2. No S presented with fewer than 120 songs learned the tutor song; 2 Ss tutored with 252 songs copied the tutor song. It is concluded that the song learning system is quite flexible, that the results obtained with tape-tutors are different from those with social tutors, and that there may be an interaction between total number of song inputs and the number presented on a single day. Implications for physiological mechanisms and the possible functional significance of the acquisition system are discussed. (30 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)