An inexpensive reinforcement dispenser

An inexpensive (less than $35) solid food reinforcement dispenser was developed using commercially available parts for commonly found vending machines. This device proved to be reliable and efficient in repeated use with laboratory primates in a video task testing situation.     

Rate differential reinforcement in monkey manipulation

A set of four manipulanda were presented to four Cebus monkeys, individually, and later in pairs. Step 1 provided an estimate of each S's probability of operating each item, while Step 2 determined whether pairing the items would disturb the ordinal relations among individual response probabilities. Both procedures provided information necessary for testing the assumption that a reinforcer is simply a contingent response whose independent probability of occurrence is greater than that of the associated instrumental response. Step 3 tested this assumption by again presenting pairs of items, but with one locked and its operation made contingent upon operation of the free item of the pair. The four Ss differed markedly in the extent to which the items produced different independent response probabilities, and correspondingly, in the extent to which the contingent pairs subsequently produced reinforcement. Confirmation of the present assumptions came primarily from one S, which differed substantially on the individual items, and showed five cases of reinforcement, all in the predicted direction. Further, reinforcement was shown by an increase in both contingency and extinction sessions. Finally, the response of intermediate probability reinforced the response of least, but not the one of greatest, probability, indicating that a reinforcer cannot be identified absolutely, but only relative to the base response.     

An economical dispenser to improve control of food reinforcement in the rat

A hopper dispenser designed for the study of food reinforcement in rats is described. By using ordinary rat chow, it significantly reduces the cost of reinforcing rats with food. By preventing stockpiling, it also guarantees control of the accessibility, as well as the presentation of food.     

A versatile cat-restraint system

A new method and apparatus for restraining the awake cat is described. The restraint system comfortably and adequately restrains virtually any cat and requires little or no adaptation. The restraint box is inexpensive to construct, lightweight, and portable. The unit requires minimal maintenance, can be easily used by one person, and may be modified for use in a variety of situations.     

A versatile memory-mapped I/O interface for microcomputers

An inexpensive and easy-to-bulid input/output interface capable of driving the electromechanical loads (relays, solenoids, dc motors, etc.) and incandescent lamps is described. The interface hardware is based on the Commodore VIC-20 microcomputer. The design is adaptable to most 8-bit microcomputers.     

A versatile microcomputer-based multiple-field tachistoscope

A newly introduced microcomputer in its most basic form provides a wide variety of stimulus display capabilities at an extremely low price. Several simple illustrative programs demonstrate its ability to present any number of visual stimuli in sequence and record response latencies, thus duplicating the functions of a multiple-field tachistoscope and associated response-recording instrumentation.     

A versatile electronic switch with memory

This noise-conditioned switch provides a convenient interface between S response switches and logic circuitry and is adaptable to many experimental situations.     

A versatile two-part system for on-line measurement of multiple response parameters

A two-part system for digital measurement of such diverse response parameters as latency, pulse width, amplitude, and events per unit time is described. The mainframe consists of counters with light-emitting diode (LED) numeric readouts and a quartz crystal controlled internal time base. It also contains all power supply requirements for both the mainframe electronics and the second part of the system, the plug-ins. Each plug-in is designed to use the main unit counters, timers, readouts, and power supplies to measure the desired parameter. Thus, each numeric readout channel of the mainframe may be used to measure various parameters simply by changing the plug-in attached to it. The unit has proved to be very useful in reducing experimenter error in measuring response parameters in classical nictitating membrane conditioning.