Types and amplitudes of touch as reinforcing stimuli in operant conditioning of infant behavior

The reinforcing effects of diverse tactile stimuli were examined in this study. The study had two purposes. First, this study expanded on the Pelaez-Nogueras, Field, Gewirtz, Cigales, Gonzalez, Sanchez and Clasky (1997) finding that stroking increases infants' gaze duration, and smiling and vocalization frequencies more than tickling/poking. Instead of presenting poking and tickling as a single stimulus combination, this study separated poking and tickling in order to measure the effects of each component separately. Further, the effects of poking, tickling/tapping and stroking intensity (i.e., tactile pressure) were compared by having both mild and intense conditions. Second, this study compared the reinforcing efficacy of mother-delivered tactile stimulation to that of infant-originated tactile exploration. Twelve infants from 2- to 5-months of age participated in this study. The experiment was conducted using a repeated measures A-B-A-C-A-D reversal design. The A phases signified baselines and reversals. The B, C, and D phases consisted of alternating treatments (either mild stroking vs. mild poking vs. mild tickling/tapping, intense stroking vs. intense poking vs. intense tickling/tapping, or mother-delivered tactile stimulation vs. infant-originated tactile exploration). Three experimental hypotheses were assessed: (1) infant leg kick rate would be greater when it produced stroking or tickling/tapping (presumptive positive reinforcers), than when it produced poking (a possible punisher), regardless of tactile pressure; (2) infant leg kick rate would be greater when it produced a more intense level of stroking or tickling/tapping and lower when it produced intense poking compared to mild poking; (3) infant leg-kick rate would be greater for mother-delivered tactile stimulation than for infant-originated tactile exploration. Visual inspection and inferential statistical methods were used to analyze the results. The data supported the first two hypotheses. Mixed support emerged for the third hypothesis. This study made several important contributions to the field of psychology. First, this was the first study to quantify the pressure of tactile stimulation, via a pressure meter developed by the researcher. Additionally, the results of this study yielded valuable information about the effects of different modalities of touch. ^

Contingency, contiguity, and development: The ontogeny of contingency learning in northern bobwhite (Colinus virginianus) chicks

The purpose of this study was to investigate the ontogeny of auditory learning via operant contingency in Northern bobwhite (Colinus virginianus ) hatchlings and possible interaction between attention, orienting and learning during early development. Chicks received individual 5 min training sessions in which they received a playback of a bobwhite maternal call at a single delay following each vocalization they emitted. Playback was either from a single randomly chosen speaker or switched back and forth semi-randomly between two speakers during training. Chicks were tested 24 hrs later in a simultaneous choice test between the familiar and an unfamiliar maternal call. It was found that day-old chicks showed a significant time-specific decrement in auditory learning when trained with delays in the range of 470–910 ms between their vocalizations and call playback only when training involved two speakers. Two-day-old birds showed an even more sustained disruption of learning than day-old chicks, whereas three-day-old chicks showed a pattern of intermittent interference with their learning when trained at such delays. A similar but less severe decrement in auditory learning was found when chicks were provided with motor training in which playback was contingent upon chicks entering and exiting one of two colored squares placed on the floor of the arena. Chicks provided with playback of the call at randomly chosen delays each time they vocalized exhibited large fluctuations in their responsivity to the auditory stimulus as a function of delay—fluctuations which were correlated significantly with measures of chick learning, particularly at two-days-of-age. When playback was limited to a single location chicks no longer showed a time-specific disruption of their learning of the auditory stimulus. Sequential analyses revealed several patterns suggesting that an attentional process similar or analogous to attentional blink may have contributed both to the observed fluctuations in chick responsivity to the auditory stimulus as a function of delay and to the time-specific learning deficit shown by chicks provided with two-speaker training. The study highlights that learning can be substantially modulated by processes of orienting and attention and has a number of important implications for research within cognitive neuroscience, animal behavior and learning.

Using sonic enhancement to augment non-visual tabular navigation

More information is now readily available to computer users than at any time in human history; however, much of this information is often inaccessible to people with blindness or low-vision, for whom information must be presented non-visually. Currently, screen readers are able to verbalize on-screen text using text-to-speech (TTS) synthesis; however, much of this vocalization is inadequate for browsing the Internet. An auditory interface that incorporates auditory-spatial orientation was created and tested. For information that can be structured as a two-dimensional table, links can be semantically grouped as cells in a row within an auditory table, which provides a consistent structure for auditory navigation. An auditory display prototype was tested.^ Sixteen legally blind subjects participated in this research study. Results demonstrated that stereo panning was an effective technique for audio-spatially orienting non-visual navigation in a five-row, six-column HTML table as compared to a centered, stationary synthesized voice. These results were based on measuring the time- to-target (TTT), or the amount of time elapsed from the first prompting to the selection of each tabular link. Preliminary analysis of the TTT values recorded during the experiment showed that the populations did not conform to the ANOVA requirements of normality and equality of variances. Therefore, the data were transformed using the natural logarithm. The repeated-measures two-factor ANOVA results show that the logarithmically-transformed TTTs were significantly affected by the tonal variation method, F(1,15) = 6.194, p= 0.025. Similarly, the results show that the logarithmically transformed TTTs were marginally affected by the stereo spatialization method, F(1,15) = 4.240, p=0.057. The results show that the logarithmically transformed TTTs were not significantly affected by the interaction of both methods, F(1,15) = 1.381, p=0.258. These results suggest that some confusion may be caused in the subject when employing both of these methods simultaneously. The significant effect of tonal variation indicates that the effect is actually increasing the average TTT. In other words, the presence of preceding tones increases task completion time on average. The marginally-significant effect of stereo spatialization decreases the average log(TTT) from 2.405 to 2.264.^

Effects of Prenatal and Early Postnatal Exposure to Aversive Stimuli on Fearfulness and Exploratory Behavior in Bobwhite Qauil Neonates (Colinus virginianus)

Neophobia, the fear of novelty, is a behavioral trait found across a number of animal species, including humans. Neophobic individuals perceive novel environments and stimuli to have aversive properties, and exhibit fearful behaviors when presented with non-familiar situations. The present study examined how early life exposure to aversive novel stimuli could reduce neophobia in bobwhite quail chicks. Experiment 1 exposed chicks to a novel auditory tone previously shown to be aversive to naïve chicks (Suarez, 2012) for 24 hours immediately after hatching, then subsequently tested them in the presence of the tone within a novel maze task. Postnatally exposed chicks demonstrated decreased fearfulness compared to naïve chicks, and behaved more similarly to chicks tested in the presence of a known attractive auditory stimulus (a bobwhite maternal assembly call vocalization). Experiment 2 exposed chicks to the novel auditory tone for 24 hours prenatally, then subsequently tested them within a novel maze task. Prenatally exposed chicks showed decreased fearfulness to a similar degree as those postnatally exposed, revealing that both prenatal and postnatal exposure methods are capable of decreasing fear of auditory stimuli. Experiment 3 exposed chicks to a novel visual stimulus for 24 hours postnatally, then subsequently tested them within a novel emergence box / T-maze apparatus. Chicks exposed to the visual stimulus showed decreased fearfulness compared to naïve chicks, thereby demonstrating the utility of this method across sense modalities. Experiment 4 assessed whether early postnatal exposure to one novel stimulus could generalize and serve to decrease fear of novelty when chicks were tested in the presence of markedly different stimuli. By combining the methods of Experiments 1 and 3, this experiment revealed that chicks exposed to one type of stimulus (auditory or visual) demonstrated decreased fear when subsequently tested in the presence of the opposite type of novel stimulus. These results suggest that experience with novel stimuli can moderate the extent to which neophobia will develop during early development.