Honeybees generalize among pollen scents from plants flowering in the same seasonal period.

When honey bees (Apis mellifera) feed on flowers, they extend their proboscis to absorb the nectar, i.e. they perform the proboscis extension response (PER). The presence of pollen and/or nectar can be associated with odors, colors or visual patterns, which allows honey bees to recognize food sources in the environment. Honey bees can associate similar, though different, stimuli with the presence of food; i.e. honey bees discriminate and generalize among stimuli. Here, we evaluated generalization among pollen scents from six different plant species. Experiments were based on the PER conditioning protocol over two phases: (1) conditioning, in which honey bees associated the scent of each pollen type with sucrose, and (2) test, in which honey bees were presented with a novel scent, to evaluate generalization. Generalization was evinced by honey bees extending their proboscis to a novel scent. The level of PER increased over the course of the conditioning phase for all pollen scents. Honey bees generalized pollen from Pyracantha coccinea and from Hypochaeris radicata These two plants have different amounts of protein and are not taxonomically related. We observed that the flowering period influences the olfactory perceptual similarity and we suggest that both pollen types may share volatile compounds that play key roles in perception. Our results highlight the importance of analyzing the implications of the generalization between pollen types of different nutritional quality. Such studies could provide valuable information for beekeepers and agricultural producers, as the generalization of a higher quality pollen can benefit hive development, and increase pollination and honey production.

Bidirectional Regulation of Innate and Learned Behaviors That Rely on Frequency Discrimination by Cortical Inhibitory Neurons.

The ability to discriminate tones of different frequencies is fundamentally important for everyday hearing. While neurons in the primary auditory cortex (AC) respond differentially to tones of different frequencies, whether and how AC regulates auditory behaviors that rely on frequency discrimination remains poorly understood. Here, we find that the level of activity of inhibitory neurons in AC controls frequency specificity in innate and learned auditory behaviors that rely on frequency discrimination. Photoactivation of parvalbumin-positive interneurons (PVs) improved the ability of the mouse to detect a shift in tone frequency, whereas photosuppression of PVs impaired the performance. Furthermore, photosuppression of PVs during discriminative auditory fear conditioning increased generalization of conditioned response across tone frequencies, whereas PV photoactivation preserved normal specificity of learning. The observed changes in behavioral performance were correlated with bidirectional changes in the magnitude of tone-evoked responses, consistent with predictions of a model of a coupled excitatory-inhibitory cortical network. Direct photoactivation of excitatory neurons, which did not change tone-evoked response magnitude, did not affect behavioral performance in either task. Our results identify a new function for inhibition in the auditory cortex, demonstrating that it can improve or impair acuity of innate and learned auditory behaviors that rely on frequency discrimination.

Effect of different diets on Tyrophagus putrescentiae population and amelioration of their immunological disorder by garlic

BACKGROUND: The storage mite, Tyrophagus putrescentiae, detected in the samples collected from stored products and house dust, is one of the major causes of allergic disorders. OBJECTIVE: The purpose of this study was to ameliorate the T. putrescentiae faeces allergic immunological disorder by garlic. METHODS: Albino experimental rats were classified into control, inhaled and treated groups. Mass rearing of T. putrescentiae on different diets, and ELISA of some cytokines and IgE techniques were used. RESULTS: The results obtained showed the highest population of T. putrescentiae reared in four from thirteen tested diets. In addition, significantly higher serum levels of INF-γ and IgE were found in rats treated with faeces than the other groups; especially the garlic-treated group. In contrast, IL-4 was lower in faeces-treated rats than the others; however, the control group had the highest level of IL-4. Statistical analysis of data showed a significant difference between the garlic-treated group and either control or faeces-treated groups (P < 0.05). CONCLUSIONS: The population of T. putrescentiae mites peaked in four from thirteen tested diets. The immunological disorder caused by repeated exposure to T. putrescentiae faeces might be modulated by garlic

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Multiple n = 1 trials in the identification of responders and non-responders to the cognitive effects of Ginkgo biloba.

OBJECTIVE: A pilot study to assess multiple crossover n = 1 trials with verum/placebo discrimination as the outcome measure as a means of identifying responders and non-responders to the acute nootropic effect of Ginkgo biloba (G. biloba) among healthy volunteers. METHOD: Multiple double-blind, placebo-controlled n = 1 trials with 8 treatments in randomized order and separated by minimum washout periods of 7 days. Treatments were acute 120 mg doses of G. biloba extract (GK501) or undistinguishable placebo. The frequency distribution of correct scores for verum-placebo discrimination was compared with the binomial distribution to identify putative responders, who were then tested for consistency of performance over a further 8 treatments. RESULTS: The frequency distribution of scores (n = 11) was bimodal and a discontinuity defined 3 putative responders and 2 putative negative responders for re-test. Two of the putative responders again performed at above chance level and the probability of achieving their scores or better by chance was 0.013 and 0.052. CONCLUSIONS: n = 1 trials with verum/placebo discrimination as outcome are a promising method for exploring response heterogeneity to treatments with a subjective effect. Preliminary evidence suggests that there are responders and non-responders to an acute G. biloba treatment among healthy subjects.

Discriminative characteristics of high and low cocaine administration: effect of other psychostimulants.

Two groups of N/Nih male rats were trained to discriminate saline vehicle from either 2.0 mg/kg (n = 10) or 10.0 mg/kg (n = 10) cocaine in a food-motivated, two-lever operant paradigm. The rats trained at the low-dose cocaine took a significantly longer training period to reach criterion performance than did the high-dose cocaine group. In addition, the ED50 value for the 2.0 mg/kg cocaine-trained animals (0.465 mg/kg) was significantly lower than the ED50 value (2.105 mg/kg) for those animals trained at the 10.0 mg/kg dose of cocaine. This correlation of ED50 values for stimulus generalization decreasing with reduction in training dose was in contrast to the time-course of the two groups when tested from 15 to 240 min post-injection; this experimentation indicated that there was a non-significant difference in half-life for the 2.0 mg/kg (t1/2: 97.1 min) vs. that of the 10.0 mg/kg cocaine-trained group (t1/2: 83.4 min). Generalization tests with other purportedly dopaminergically-active drugs of abuse including 0.05-0.8 mg/kg d-amphetamine, 0.125-1.5 mg/kg methamphetamine and 0.125-1.0 mg/kg methcathinone indicated that the highest doses of each produced generalization and, with the exception of methcathinone, the ED50 values were significantly lower in the low-cocaine trained group. The stimulus properties of cocaine, as they generalize to amphetamine, methamphetamine and methcathinone, can be explained by effects upon central dopaminergic neurons and may be qualitatively different in low-and high-dose trained rats.

The effects of cue control relaxation on adults with severe mental retardation.

This study was designed to assess two aspects of behavioural relaxation training with subjects who have severe mental retardation. The first was whether or not cue words could be linked effectively to training so that they would eventually produce a relaxation effect in the absence of a full relaxation procedure. The second was to determine the effects of relaxation training and subsequent cue control on concentration and attention to an occupational task. Five subjects participated, and individual case designs were used. Cue Control, behavioural relaxation training (BRT), and new therapists were introduced at different times for each subject to ascertain the effects of each variable. Subjects were assessed at baseline and following each training session on a behavioural relaxation scale to judge the direct effects of relaxation training and on the amount of time spent concentrating on an occupational task. BRT produced reductions in rated anxiety and improvements in concentration for all subjects. The cue control words were effective only after they had been linked to BRT. In most cases, the introduction of a new therapist had no appreciable effect on anxiety or concentration. There was some suggestion that in the final cue only phases concentration was better and more consistent than during the BRT phases of the study.

Teaching preschool children with disabilities to respond to the lures of strangers.

An investigation was conducted to determine the effectiveness of a constant-time-delay procedure used in combination with multiple exemplars of strangers, lures, and sites to teach a generalized response to the lures of strangers to four preschool children with disabilities. Although the correct response was quickly acquired in the training site, the response failed to generalize to the probe sites until training was conducted in vivo. Instruction in vivo resulted in acquisition, maintenance, and generalization of the response to strangers' lures. Generalization occurred across probes with novel exemplars of lures, strangers, and sites.

Teaching children with autism to initiate to peers: effects of a script-fading procedure.

A script that was systematically faded from end to beginning was used to teach peer initiations about recently completed, current, and future activities. The effectiveness of the script-fading procedure was assessed via a multiple baseline design across 4 children with autism. During baseline, the children seldom initiated to peers, although all had previously acquired some functional expressive language and sometimes spontaneously addressed adults. When the script was introduced, peer initiations increased, and as the script was faded, unscripted initiations increased. With the minimal written prompts available in the final fading steps, initiations generalized to a different setting, time, teacher, and activity; and for 3 of the 4 children, peer initiations were maintained at a 2-month follow-up. After the script was faded, the participants' levels of peer initiations were within the same range as a normative sample of 3 nondisabled youngsters. The script-fading procedure enabled children with severe social and verbal deficits to practice context-specific, peer-directed generative language that was not prompted by adults or peer confederates.

Teaching mentally handicapped adults how to use a cafeteria.

This study taught three moderately to severely mentally handicapped women skills to enable them to make use of cafeterias. While some work has been carried out in this area (e.g. Marholin et al., 1979; Van den Pol et al., 1981; Desai, 1983), it has not established whether hospital-based individuals with this level of handicap and no previous experience of cafeterias can be taught how to use them. A role-playing procedure was used during training with in vivo assessments being carried out before and after training. An in vivo generalization assessment was also conducted. Training was found to be successful with the skills taught transferring to the real life situation and subjects' improved performance, in the majority of the skill areas, generalizing to a 'new' cafeteria which had a completely different system of use.

Generalization of EMG biofeedback training.

Five young adults received audio biofeedback training to reduce trapezius EMG levels while they engaged in reading in an office, seated at a table. A multiple-baseline-across subjects design was employed in two separate studies. After training, all subjects demonstrated reduced EMG levels while reading in a home or library setting. The first study suggested that subjects reduced EMG levels by minimizing movements and altering their postures; the second study systematically demonstrated changes in such behavior, which was correlated with EMG levels. The data provide evidence that EMG biofeedback resulted in response generalization across several motoric classes, and in stimulus generalization from the training setting to the natural environment. The importance of assessing generalization is discussed.

Wh interrogative production in agrammatic aphasia: an experimental analysis of auditory-visual stimulation and direct-production treatment.

The effects of auditory-visual stimulation treatment derived from principles associated with a stimulation approach for aphasia treatment and direct-production treatment derived from a behavioral or learning approach were examined in 4 neurologically stable agrammatic aphasic subjects. Subjects were trained to produce selected exemplars of wh interrogative morphemes in complete sentence contexts, while the acquisition, response generalization (both within and across interrogative forms), stimulus generalization (to language samples), and maintenance effects of the two treatments were assessed. An alternating treatments design (ATD) in combination with a multiple-baseline design across behaviors and a multiple-baseline design across subjects was employed. Interrogative constructions were counterbalanced across subjects and treatments, and probes were administered daily to assess treatment effects. Results indicated that direct-production treatment was consistently more effective than auditory-visual stimulation treatment in facilitating acquisition of target responses for all subjects. Response generalization within interrogative forms paralleled acquisition regardless of treatment approach. Stimulus generalization to the elicited language-sample condition was not evident, however, trained responses were maintained subsequent to treatment. These data provided support for using direct-production treatment for interrogative intervention with agrammatic aphasic patients and indicated that training a selected number of exemplars of target interrogatives results in generalization of that question form to novel language responses. However, the lack of generalization across interrogatives indicated that wh interrogatives do not constitute a response class and, thus, pointed out a need for programming generalization to untrained members of that linguistic class and to spontaneous language.

Using biofeedback to reduce left arm extensor EMG of string players during musical performance.

Electromyographic (EMG) feedback offers a mechanism for helping musicians reduce specific muscle tension during performance. Nine intermediate to advanced level string players participated in a four-session, pretest/posttest design study to determine (1) if left forearm extensor EMG could be reduced using biofeedback, (2) if reductions in EMG would generalize to a no-feedback condition, and (3) if reductions in EMG would generalize from extensors to flexors. Results indicate that biofeedback did facilitate significant decreases in EMG, that the reductions in EMG did generalize to a no-feedback condition, and that generalization from extensors to flexors did not occur.

Generalization of frontalis electromyographic feedback to adjacent muscle groups: a critical review.

The widespread utilization of frontalis electromyographic feedback as a general relaxation strategy far preceded empirical evidence demonstrating its efficacy for this purpose. This article reviews parametric studies testing the association between frontalis reduction and concomitant EMG decreases in nontargeted muscle groups. The current research supports the contention that biofeedback reinforces discriminative responding to a specific muscle group and not generalized relaxation to adjacent muscle groups. Methodological problems are noted, and implications for future research are addressed.

Maintenance and generalization of 40-Hz EEG biofeedback effects.

Maintenance of conditioning of 40-Hz EEG activity was investigated in six adults 1 to 3 years after they had experienced biofeedback training to increase 40-Hz EEG. Subjects were first retrained to alternately increase and suppress 40-Hz EEG. All six subjects achieved a preset performance criterion in 16-20 minutes. Five of these subjects also subsequently demonstrated significant control of 40-Hz EEG without feedback. The sixth subject did not demonstrate control after 76 minutes and four sessions of attempted retraining with feedback. Transfer of 40-Hz EEG control to a problem-solving task was tested in all subjects in a final session. Cognitive test items were presented and subjects were instructed to alternately increase and suppress 40-Hz EEG while solving the problems. Rates of 40-Hz EEG in suppression periods during problem solving wer significantly greater than during suppression periods without problems. No significant differences in problem-solving performance were found comparing 40-Hz increase and suppression periods. This study supports previous research suggesting an association between 40-Hz EEG and mental activity, and suggests methods for further study of transfer of EEG biofeedback effects.

An experiment to test generalization of feedback from frontalis EMG.

60 subjects participated in a test of the effectiveness of frontalis EMG feedback as a generalized relaxation technique. The experiment was performed in two parts. In the first part, 30 subjects were randomly allocated to a group receiving frontalis EMG feedback (n = 10), a group receiving non-contingent feedback (n = 10) and a group instructed to relax themselves (n = 10). Each group received one baseline session and five training sessions. EMG measurements from the frontalis, trapezius and masseter muscles taken prior to and immediately after the final training session indicated that the frontalis feedback group was more effective in lowering frontalis and masseter EMG activity (though not trapezius activity) than the controls. The second part of the experiment was identical to the first with the exception that the subsidiary muscle sites were the forearm and leg extensors. The results showed that frontalis feedback was no more effective than controls in lowering the EMG levels of these muscles.

A biobehavioral model of obesity.

Recent research contributing to an increased understanding of human feeding is reviewed and implications for obesity discussed. Hyperphagia may represent the manifestation of diverse origins requiring different therapeutic strategies. A biobehavioral model of obesity designed to promote increased efficacy of treatment interventions with the overweight is proposed.