摘要:

Six pigeons were trained to match wavelengths in a three‐key matching‐to‐sample paradigm. Test trials were occasionally presented, where probe wavelengths appeared on the center key and choices were made to the training stimuli presented on the side keys. Color naming functions were obtained by plotting the percentage of test trials that each training stimulus wavelength was chosen for each center key probe wavelength. The wavelength where the functions intersected was interpreted as a transition point between pigeon hues. Three experiments employed different wavelengths as training stimuli. The first two experiments demonstrated that the intersection of the color‐naming functions occurred in all cases at 540 nm and 595 nm. The third experiment employed 540 nm and 595 nm as two of the three training stimuli, and the relatively slow acquisition, together with the resulting color‐naming functions, supported the proposition that 540 nm and 595 nm may be transition point wavelengths between pi

ISSN:0022-5002    

DOI:10.1901/jeab.1971.15-7

出版商:Blackwell Publishing Ltd    

年代:1971

数据来源: WILEY

摘要:

The effects of briefly presented stimuli paired or not paired with food reinforcement were investigated in the pigeon on a multiple schedule containing second‐order schedules. A stimulus paired with food reinforcement was presented on a variable‐interval schedule in one unit of the multiple schedule and either a stimulus not paired with food reinforcement or no stimuli were scheduled in the other unit. Response rates were highest when behavior was followed by the food‐paired stimulus. Presentation of the food‐paired stimulus at completion of each 1‐min variable‐interval component maintained a steady rate of responding between consecutive food presentations. Pausing following food reinforcement was greatest in the second‐order schedule not containing the paired stimulus. Reversing the stimulus pairings led to a reversal of the relative response rates and patterns of responding for

ISSN:0022-5002    

DOI:10.1901/jeab.1971.15-19

出版商:Blackwell Publishing Ltd    

年代:1971

数据来源: WILEY

摘要:

Pigeons' responses in the presence of two concurrently available (initial‐link) stimuli produced one of two different (terminal‐link) stimuli. Entrance into the mutually exclusive terminal links was arranged by different and independent variable‐interval schedules for each key, while responses during the mutually exclusive terminal‐link stimuli produced a single food reinforcement according to identical and independent variable‐interval schedules. The pigeons emitted more initial‐link responses on the key with the shorter average inter‐reinforcement interval in the initial link. This difference in initial‐link response rates varied directly with the difference between the average inter‐reinforcement intervals of the initial‐link schedules and decreased when the initial‐link schedule with the longer average interreinforcement interval was followed by several consecutive food reinforcements on the variable‐interval schedule in the terminal link on that key. These results are incompatible with previous formulations of choice behavior with the concurrent‐chains procedure. A modified formulation with a multiplier for the overall rate of primary reinforcement obtained on each key provides a better description of choice. In addition, the new formulation applies to behavior in simple (concurrent) choice situations, an advantage not achieved

ISSN:0022-5002    

DOI:10.1901/jeab.1971.15-27

出版商:Blackwell Publishing Ltd    

年代:1971

数据来源: WILEY

ISSN:0022-5002    

DOI:10.1901/jeab.1971.15-39

出版商:Blackwell Publishing Ltd    

年代:1971

数据来源: WILEY

摘要:

The performance of pigeons was studied under a second‐order schedule composed of fixed‐interval components, each of which was associated with a different discriminative stimulus, the stimuli occurring in a fixed order. In one condition, food presentation followed the completion of the fourth component. This was designated a fixed‐ratio sequence schedule. In another condition, responses in the first component completed after a fixed time were reinforced. This was designated a fixed‐interval sequence schedule. Although the stimulus order and maximum reinforcement frequency were identical under the two schedules, considerably more responding occurred under the fixed‐interval sequence schedule in all components. Relatively few food presentations occurred after responding during any but the terminal components of the fixed‐interval sequence schedule, a feature independent of the parameter values investigated. In addition, while a pattern of increased responding between food presentations prevailed under both schedules, under the fixed‐interval sequence schedule the rate in the terminal component was frequently less than in the penultimate component. The fixed‐interval sequence schedule appeared to have several properties of simple fixed‐i

ISSN:0022-5002    

DOI:10.1901/jeab.1971.15-41

出版商:Blackwell Publishing Ltd    

年代:1971

数据来源: WILEY

摘要:

Five pigeons whose key pecking was maintained by 4‐sec access to grain on a variable‐interval 2‐min schedule received Pavlovian differential conditioning trials superimposed upon the instrumental baseline. The conditioned stimuli were changes in the stimulus on the key from white to red, or to a white horizontal line against a dark background. The positive conditioned stimulus was 20 sec long, and was followed immediately by 8‐sec access to grain. The negative conditioned stimulus, also 20 sec long, was never paired with response‐independent food. All pigeons responded more rapidly in the presence of the positive conditioned stimulus than in the presence of the negative one. The positive conditioned stimulus produced an increase in response rate over the pre‐conditioned stimulus period. The negative conditioned stimulus had no marked effect upon response rate. When the roles of the positive and negative stimuli were reversed, and the duration of the response‐independent reinforcement was reduced to 4 sec, the new positive conditioned stimulus came to facilitate responding, and the new negative conditioned stimulus no longer produced facilitation. A second discrimination reversal produced similar outcomes. When a third reversal was initiated, and the duration of response‐independent reinforcement was reduced to 2 sec, the difference between the effects of the positive and negative sti

ISSN:0022-5002    

DOI:10.1901/jeab.1971.15-49

出版商:Blackwell Publishing Ltd    

年代:1971

数据来源: WILEY

摘要:

The acuity of six pigeons was measured in an apparatus that required the birds to make visual discriminations at a distance of 28.75 in. (73 cm) from the stimulus targets. The stimuli were black and white gratings of varying stripe width. A forced choice procedure was used, and both the Method of Constant Stimuli and a descending series technique determined the order of stimulus presentation. Thresholds, obtained by interpolating at the 25% error point on the psychometric functions, ranged from 1.16 to 4.0 min of arc. Thresholds measured in the same apparatus for two human observers were 0.79 and 0.82 min of arc. The descending series design produced lower per cent error rates at the widest stripe value, but otherwise there appeared to be no difference between psychophysical methods. Position preferences occurred in most of the birds; differential per cent error functions and differential latency functions to the two keys illustrate these. Retinal histology revealed shallow, centrally located foveae in the three pigeon breeds used.

ISSN:0022-5002    

DOI:10.1901/jeab.1971.15-57

出版商:Blackwell Publishing Ltd    

年代:1971

数据来源: WILEY

ISSN:0022-5002    

DOI:10.1901/jeab.1971.15-69

出版商:Blackwell Publishing Ltd    

年代:1971

数据来源: WILEY

摘要:

Pigeons were exposed to two keys, a main key and a changeover key. Initially non‐differential training was given in which pecking the main key was reinforced on a variable‐interval 2‐min schedule when the key displayed the first stimulus, a black line on a blue background, and was reinforced on an identical but independent variable‐interval 2‐min schedule when the key displayed a plain blue stimulus. Later, differential training was given in which pecking the main key was reinforced on a variable‐interval 2‐min schedule when the first stimulus was displayed; and was reinforced on a variable‐interval 10‐min schedule when a second stimulus, a black line of another orientation on a blue background, was displayed. During non‐differential and differential training, each peck on the changeover key changed the stimulus on the main key. Generalization tests were given before and after the differential training. These consisted of presentations on the main key of seven orientations of the black line on the blue background, including the first and second stimuli, with no reinforcements being given. Changeover‐key pecks changed the stimuli on the main key. Generalization gradients were obtained using three measures: time spent, responses, and response rate in the presence of each test stimulus. Typically, maximum values on these measures occurred to stimuli away from the first in a direction opposite the second stimulus, and minimum values occurred to stimuli away from the second in a directi

ISSN:0022-5002    

DOI:10.1901/jeab.1971.15-73

出版商:Blackwell Publishing Ltd    

年代:1971

数据来源: WILEY

摘要:

Ethological recording procedures measured collateral behavior in pigeons whose key‐pecking performance was suppressed during a tone that ended with unavoidable electric shock. Independent recordings of gross behavior were made by two observers throughout 60‐sec intervals immediately before, during, and after tone presentation. Results indicated significant reductions in the frequency of collateral movements and an increase in the time between successive movements during tone presentations. These effects were observed in all subjects, despite differences in the sequential patterns of behavior. Only partial recovery of the behavior evidenced before tone presentation was found during a 60‐sec interval following shock. It was concluded that conditioned suppression procedures caused the bird to “freeze” during tone presentation and in this fashion produced a general inhibitory effect on ongoing overt activity, including ke

ISSN:0022-5002    

DOI:10.1901/jeab.1971.15-83

出版商:Blackwell Publishing Ltd    

年代:1971

数据来源: WILEY