How big is this sound? Crossmodal association between pitch and size in infants

We examined 4- and 6-month-old infants’ sensitivity to the perceptual association between pitch and object size. Crossmodal correspondence effects were observed in 6-month-old infants but not in younger infants, suggesting that experience and/or further maturation is needed to fully develop this crossmodal association.     

Pigeons can discriminate locations presented in pictures

The present experiments were designed to teach pigeons to discriminate two locations represented by color photographs. Two sets of photographs were taken at two distinctive locations on a university campus. These sets represented several standpoints at each location. For the true-discrimination group, pictures from the two locations were differentially associated with reward; for the pseudodiscrimination group, half of the views from each location were arbitrarily but consistently associated with reward. The former group acquired the discrimination much more rapidly. These birds also showed good transfer to new views from the standpoints used in training and to a new standpoint at each location not used in training. In a second experiment, another group of pigeons could terminate any training trial by pecking an “advance” key. Three of 4 subjects used this option to reduce the duration of trials in which pictures from the negative location were presented. These data suggest that pigeons can integrate views shown in pictures into a “concept” of a location. The method used here may be the experimental analogue of a common, natural process by which animals learn to identify locations.     

Purposive behaviour in cognition and perception: Considerations of awareness in memory

The responses to the original article by Rönnberg (1990a) provoked interesting and thoughtful points of view that are covered by Gärling (1990), Hjelmquist (1990), Montgomery (1991), and Runeson (1990). These articles do not merely present a different outlook but also provide concepts that are certainly worthy of consideration and add more substance to the general topic under discussion. The purpose of this commentary is to seek an understanding of the ideas presented by the above authors within a synthesis of our views of current conceptualizations in cognition and perception. Each of the original criteria (Rönnberg, 1990a) will be treated in turn.     

繁殖群中婴幼川金丝猴社会关系发展的个案研究

使用瞬时取样法,对繁殖笼内出生的两只婴幼川金丝猴进行连续22个月的行为记录。结果表明,川金丝猴婴猴断乳大约在19—20月龄;断乳表现为母婴之间矛盾冲突的过程;群内其他雌性对初生婴儿表现出明显的抢婴、护婴和育婴行为;父亲对婴幼猴表现出接纳和容忍的态度;婴儿在断乳前是群内全体成员保护和爱护的对象,以后开始进入社会关系网,受到成年个体的责备,但很轻微;雌性幼猴在32月龄时尚未被记录到对群内成员表现威胁、蜷缩和匍伏等行为模式。     

An infrared system for the detection of a pigeon''s pecks at alphanumeric characters on a TV screen: the dependency of letter detection on the predictability of one letter by another.

Three pigeons pecked at letters of the alphabet and at the symbol "?" displayed on a computer-driven cathode ray screen. A 4 by 4 matrix of infrared emitting and detecting diodes and associated circuitry identified the location of a pigeon''s responses to the screen. Responses at the target letter T were probabilistically reinforced with food whenever T appeared in a string of three letters in the middle of the screen. Responses at the symbol "?" appearing below this string were probabilistically reinforced whenever T did not appear. The letter F anywhere in the three-character string either strongly predicted the occurrence of the target letter T, in two conditions, or predicted its nonoccurrence, in a third. This manipulation of the frequency with which the familiar letter F predicted T was shown to change the function relating probability of a correct peck at the symbol "?" to the number of Fs in the string. This effect may be interpreted as an instance of the phenomenon where an organism''s acquired knowledge changes what it sees.