The masking of octave-band noise by broad-spectrum noise: A comparison of infant and adult thresholds

Localization responses to a 4,000-Hz octave-band noise in a background of broad-spectrum noise were obtained from infants, 6, 12, 18, and 24 months of age, and adults. A two-alternative, forced-choice procedure was used to determine thresholds at each of two levels of masking noise, 42 and 60 dBC. Adults were also tested for their localization of pure tones in noise and their detection of octave-band noises with the more traditional two-interval, forced-choice task. Increasing the masking noise from 42 to 60 dBC resulted in comparable threshold shifts for all age groups. However, infant thresholds were 16–25 dB higher than those obtained for adults. The theoretical implications of these findings are discussed.     

Low-cost microcomputer networking: How to get high throughput on a low budget

A very low-cost, high-throughput laboratory data acquisition and experiment control system may be configured by using a star network architecture with a low-cost microcomputer as network controller and one or more microprocessor-based single-board controllers as satellites. A network of this type, using Apple II microcomputer ($1,500 with 48K RAM and one minidiskette drive) as main node and up to seven KIM-1 microcontrollers ($159 each) as satellites is described, and its development is discussed in detail.     

A Multimethod Exploration of the Friendships of Children Considered Socially Withdrawn by Their School Peers

Friendships of children considered socially withdrawn by their school peers were investigated within a population of elementary school children. Reciprocal friends were identified by a friendship nomination procedure; social withdrawal was assessed by peer nominations. Trained graduate students rated videotapes of dyads of friends (n = 58 dyads, of which 29 contained at least one withdrawn child) for selected features of friendship quality. In addition, each friend within a dyad provided ratings of the quality of the relationship. The videotaped data showed the withdrawn children to be somewhat restricted in their verbal communication with their friends, and less competitive with their friends, than were friends in a comparison group. In dyads consisting of one withdrawn and one nonwithdrawn child, the withdrawn child perceived the relationship as characterized by greater closeness and helpfulness than did the nonwithdrawn friend. Despite some signs of inhibited behavior within the friendship context, withdrawn children seem to have access to close friendships of high quality.