Abnormal eye movements in hyperkinetic children with learning disability

Eye movements were studied in 29 school children aged 6--12 years diagnosed as having Hyperactivity (HA) with Learning Disabilities (LD) and compared to an age matched control group of 32 children. The children had to track a moving target on a metronome and a canopy, to maintain eye fixation on a stationary target and to read a standard reading material. Accuracy, nystagmoid, reversal and overshoot movements were observed, as well as head movements and blinks. Persistence and deviations were monitored during fixation; duration, accuracy, number of fixations and reversals were monitored during reading. The tracking accuracy and fixation persistence were significantly inferior in the HA-LD children as compared to the control group in most items. This correlated well with the inferior performance on the reading task. This study supports the hypothesis that children with MBD and learning disabilities have primary defects in the motor control of eye movements which contribute significantly to their reading difficulties.

The relationship of some copper (II) complexes of facultative tetrathioethers to the coordination environment in the "blue" copper proteins

The facultative potentially tetradentate thioether ligands 1,2-bis(methylthioethylthio)ethane (2,2,2), 1,3-bis(2-methylthioethylthio)propane (2,3,2) and 1,2-bis(3-methylthiopropylthio)ethane (3,2,3) react with copper(II) salts to form Cu2(2,2,2)Cl4, Cu3(ligand)X6 (ligand = 2,3,2 and 3,2,3 X = Cl; ligand = 2,2,2 2,3,2 and 3,2,3 X = Br), and Cu(ligand)(ClO4)2. The stoichiometry and structures of these complexes are discussed in terms of the steric demands of the ligand and the nature of the halide. The [Cu(2,3,2)(ClO4)] ClO4 and [Cu(3,2,3)(ClO4) [ClO4 complexes have electronic spectra which exhibit the intense 600 nm band characteristic of the "blue" copper proteins. In fact, the spectrum of [Cu(2,3,2)(ClO4)]ClO4 is very similar to that of pseudomonas aeroginosa azurin.

Automatic operant response procedure ('play-test') for the study of auditory perception of neurologically impaired infants

Ten babies with cerebral palsy of varying types and degrees (age-range 10 to 27 months) participated in an initial exploratory study designed to determine the effectiveness of an automated, two-choice audio feedback system (Playtest') for evaluation of the auditory perception and processing capabilities of neurologically impaired infants. The major components of the 'Playtest' are a master control unit and two toy-like switches which are attached to the baby's crib. By playing with the 'toys', the baby is able to listen to one of two pre-recorded audio stimuli, music or a monotone hum. Frequency and duration of the baby's self-selected listening responses are automatically recorded on meters inside the control unit and provide a precise numerical record over an extended period of time. In this study the handicapped infants were physically able to operate the apparatus and demonstrated highly significant preferential listening. Comparison of the recorded data from the study infants with those from normal infants showed no significant difference between the performances of the two groups. The findings suggest that the 'Playtest' technique could be successfully applied to the objective assessment of auditory perception and processing abilities of neurologically impaired infants, whose handicaps often prevent them from effectively participating in other standardised test procedures. The principal advantages of the technique are that testing is done in the child's most familiar environment--his own crib at home--without the intrusion of other people, and the evaluation of hearing competence is a function of the baby's spontaneous self-selected responses to sound variables, and hence of his auditory discrimination.

Family rubella study in Los Angeles

A prospective study was initiated before the expected rubella epidemics in 1964 and 1965 in Los Angeles. Seventy-six families were evaluated by means of rubella complement fixing (cf) antibodies. The cf test, which has notable limitations, was chosen as a serologic test because it was possible to secure repeated samples of sera from all members of the families if venipuncture could be avoided. Definite evidence of clinical or serological rubella occurred in 13 of 399 persons enrolled in 1964, an attack rate of 3.3 percent. Four persons had clinical rubella only, five had clinical disease with seroconversion and four had seroconversion only. The ratio of apparent to unapparent disease was nine to four. There were four key families, each of which had more than one individual with definite clinical or serological evidence of rubella, suggesting that clustering of rubella cases does occur in families having an index case. In these families three types of intra-family spread were demonstrated: (1) all affected members had clinical disease, (2) all those affected had only inapparent disease, and (3) both apparent and inapparent disease in the same family.

Visual and auditory information processing in children and adults

Children of three ages were compared with adults in a recognition experiment requiring continuous processing of information. The growth in precision for visually presented words is steeper than for auditorially presented words, largely because the former are harder for the first graders and, to a lesser extent, for the third graders. In adults, visual processing of information is at least as good as auditory. The use of receiver operating characteristic curves in describing the data permit greater precision in estimating the capacity of the individual subjects and are particularly useful since the errors of failure to recognize were different from ordinary errors of false recognition, and they occurred in large numbers.

Redundancy in Children's Texts

The sequential constraints of pairs of letters were computed for a series of graded readers. Information in single letters is about the same for all texts. Redundancy decreases with increasing grade in a regular way, while mean word length increases. A third reader has about the same redundancy as simple adult text. The constraints in a first reader are considerable, whereas those in a fifth reader approach those in average adult text.