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R D Ray

Publications and source records attributed to R D Ray.

At least 73 records · Page 4Linked to original sources
PubMedDate not supplied

The behavioral specificity of stimulation: a systems approach to procedural distinctions of classical and instrumental conditioning.

This paper presents a new methodological approach to classical Pavlovian investigations. Using a yoked group for stimulus pairing trial pacing, behavioral occurrence frequencies, sequential behavior patterns, and behavioral change dynamics are analyzed for rats in both a non-discriminative and a general setting discrimination paradigm. Theoretical issues addressed by a variety of new dependent measures are discussed, and a special emphasis is placed on comparing instrumental and classical procedures as viewed from the behavioral perspective of the subject.

Animals↗
PubMedDate not supplied

Physiological-behavioral coupling research in the Soviet science of higher nervous activity: a visitation report.

Behavioral research paradigms presently used by Soviet scientists to explore relations between behavioral and physiological activities are discussed. Each laboratory represented was physically visited by the author during a six month exhange visit to the Soviet Union. Research ranging from central concommitants of language and meaning to biofeedback and peripheral autonomic functions are described.

Animals↗
PubMedDate not supplied

Intraosseous pressure in the lumbar spine.

Intraosseus pressure in the lumbar spine is defined as the hydrostatic pressure of venous blood in the trabecular sinusoids of cancellous bone. Measurements of it in the lumbar vertebrae and the inferior vena cava confirm that the intraosseus pressure in the lumbar spine is identical to, and dependent upon, the pressure in the inferior vena cava. With Valsalva maneuver in the decubitus position, the pressure reaches levels of 90 mm Hg in the inferior vena cava and intraosseus space of lumbar spine.

Adult↗
PubMedDate not supplied

Hormonal effects on the morphology of bone defect healing.

Standard defects were produced in the radii of hypophysectomized immature rats. All animals were injected with Methimazole, and grouped according to hormone supplementation, growth hormone (GH), thyroxine (T4), the combination, or no hormones. Lack of GH and T4 caused a retardation of defect healing and callus formation but not a total cessation. The presence of GH in the hypophysectomized animal caused a larger callus due to greatly increased chondrogenesis throughout the 6 week study. Thyroxine in the hypophysectomized animal increased bone metabolism and caused more cartilage and bone formation than seen in the hormone deficient group, but not as great as that seen in the GH injected animals or the T4 and GH injected animals. Growth hormone allowed greater chondrogenesis; T4 enhanced maturation to bone. The combination allowed the development of a callus similar in stage and proportion of tissue to that observed in the pituitary intact animals. The influences of GH and T4 on the healing of a bone defect in the immature rat correspond to influences of GH and T4 on growing epiphyseal plate.

Animals↗
PubMedDate not supplied

The function of the anconeus muscle.

The purpose of the present study is to determine whether the anconeus muscle contracts during abduction of the ulna. Abduction of the ulna occurs when pronation takes place around an axis passing through the head of the radius and the second digit. This is in contrast to pronation around an axis passing through the fifth digit, in which the ulna remains relatively stationary. Electromyograms of the anconeus were obtained from five subjects with the elbow supported in 90 degrees of flexion, in full extension, at rest, during supination-pronation around an axis passing through the fifth digit, and during motion around an axis through the second digit. Pronation of the forearm around the axis through the second digit resulted in the greatest amplitude of individual motor unit action potentials and the highest recruitment of additional action potentials. These findings provide evidence substantiating the function of the anconeus muscle as an abductor of the ulna.

Action Potentials↗