University Professor Lecture: Near-Death Experiences: The Stories They Tell

I argue that we can interpret the stories told by near-death experiences (NDEs) in a naturalistic way. Thus, the profound significance of NDEs need not come from a supernaturalistic conception of them, according to which in an NDE the individual is in touch with a heavenly realm. We can respect the sincerity of NDE reports, but we can capture their meaning in a naturalistic framework.     

Testing domain general learning in an Australian lizard

A key question in cognition is whether animals that are proficient in a specific cognitive domain (domain specific hypothesis), such as spatial learning, are also proficient in other domains (domain general hypothesis) or whether there is a trade-off. Studies testing among these hypotheses are biased towards mammals and birds. To understand constraints on the evolution of cognition more generally, we need broader taxonomic and phylogenetic coverage. We used Australian eastern water skinks (Eulamprus quoyii) with known spatial learning ability in three additional tasks: an instrumental and two discrimination tasks. Under domain specific learning we predicted that lizards that were good at spatial learning would perform less well in the discrimination tasks. Conversely, we predicted that lizards that did not meet our criterion for spatial learning would likewise perform better in discrimination tasks. Lizards with domain general learning should perform approximately equally well (or poorly) in these tasks. Lizards classified as spatial learners performed no differently to non-spatial learners in both the instrumental and discrimination learning tasks. Nevertheless, lizards were proficient in all tasks. Our results reveal two patterns: domain general learning in spatial learners and domain specific learning in non-spatial learners. We suggest that delineating learning into domain general and domain specific may be overly simplistic and we need to instead focus on individual variation in learning ability, which ultimately, is likely to play a key role in fitness. These results, in combination with previously published work on this species, suggests that this species has behavioral flexibility because they are competent across multiple cognitive domains and are capable of reversal learning.     

Well-being in major depression and social phobia with and without comorbidity

Background/Objective: Lower levels in well-being have been observed in individuals with Major Depression (MDD) and Social Phobia (SP), but well-planned direct comparisons with control individuals, not suffering from a mental disorder, are lacking. Furthermore, MDD is highly comorbid with anxiety disorders, and SP with depressive disorders. This study is among the first to examine differences in well-being in individuals with a clinical diagnosis of MDD or SP compared to individuals with no such diagnosis and to test differences in well-being within the combined diagnostic categories respective with and without anxiety-depressive comorbidity. Method: Participants were 119 individuals with a diagnosis of MDD, 47 SP and 118 controls. Results: Results revealed that overall well-being as well as emotional, psychological, and social well-being were lower in the MDD and SP group compared to the control group. Individuals with comorbidity reported lower well-being than individuals without comorbidity. Conclusions: These findings have clinical implications as presence of comorbidity may require a different therapeutic approach than with no comorbidity.     

PERMA and the building blocks of well-being

Seligman (2011) hypothesized that PERMA (Positive Emotion, Engagement, Relationships, Meaning, and Accomplishment) are the elements of well-being. Goodman, Disabato, Kashdan & Kaufmann (2017) reported strong evidence that subjective well-being is the final common path of such elements and their data are entirely consistent with Seligman’s hypothesis. They argued, incorrectly however, that he suggested that PERMA constituted a different kind of well-being rather than just its building blocks. The complicated issue, one that transcends psychometrics, of how to decide on elements of well-being is discussed.     

Sound specificity effects in spoken word recognition: The effect of integrality between words and sounds

Recent evidence has shown that nonlinguistic sounds co-occurring with spoken words may be retained in memory and affect later retrieval of the words. This sound-specificity effect shares many characteristics with the classic voice-specificity effect. In this study, we argue that the sound-specificity effect is conditional upon the context in which the word and sound coexist. Specifically, we argue that, besides co-occurrence, integrality between words and sounds is a crucial factor in the emergence of the effect. In two recognition-memory experiments, we compared the emergence of voice and sound specificity effects. In Experiment 1 , we examined two conditions where integrality is high. Namely, the classic voice-specificity effect (Exp. 1a) was compared with a condition in which the intensity envelope of a background sound was modulated along the intensity envelope of the accompanying spoken word (Exp. 1b). Results revealed a robust voice-specificity effect and, critically, a comparable sound-specificity effect: A change in the paired sound from exposure to test led to a decrease in word-recognition performance. In the second experiment, we sought to disentangle the contribution of integrality from a mere co-occurrence context effect by removing the intensity modulation. The absence of integrality led to the disappearance of the sound-specificity effect. Taken together, the results suggest that the assimilation of background sounds into memory cannot be reduced to a simple context effect. Rather, it is conditioned by the extent to which words and sounds are perceived as integral as opposed to distinct auditory objects.     

Two hands are better than one: a new assessment method and a new interpretation of the non-visual illusion of self-touch

A simple experimental paradigm creates the powerful illusion that one is touching one’s own hand even when the two hands are separated by 15 cm. The participant uses her right hand to administer stimulation to a prosthetic hand while the Examiner provides identical stimulation to the participant’s receptive left hand. Change in felt position of the receptive hand toward the prosthetic hand has previously led to the interpretation that the participant experiences self-touch at the location of the prosthetic hand, and experiences a sense of ownership of the prosthetic hand. Our results argue against this interpretation. We assessed change in felt position of the participant’s receptive hand but we also assessed change in felt position of the participant’s administering hand. Change in felt position of the administering hand was significantly greater than change in felt position of the receptive hand. Implications for theories of ownership are discussed.     

The difficult mountain: enriched composition in adjective–noun phrases

When readers need to go beyond the straightforward compositional meaning of a sentence (i.e., when enriched composition is required), costly additional processing is the norm. However, this conclusion is based entirely on research that has looked at enriched composition between two phrases or within the verb phrase (e.g., the verb and its complement in . . . started the book . . .) where there is a discrepancy between the semantic expectations of the verb and the semantics of the noun. We carried out an eye-tracking experiment investigating enriched composition within a single noun phrase, as in the difficult mountain. As compared with adjective–noun phrases that allow a straightforward compositional interpretation (the difficult exercise), the coerced phrases were more difficult to process. These results indicate that coercion effects can be found in the absence of a typing violation and within a single noun phrase.     

Color modulates olfactory learning in honeybees by an occasion-setting mechanism

A sophisticated form of nonelemental learning is provided by occasion setting. In this paradigm, animals learn to disambiguate an uncertain conditioned stimulus using alternative stimuli that do not enter into direct association with the unconditioned stimulus. For instance, animals may learn to discriminate odor rewarded from odor nonrewarded trials if these two situations are indicated by different colors that do not themselves become associated with the reward. Despite a growing interest in nonelemental learning in insects, no study has so far attempted to study occasion setting in restrained honeybees, although this would allow direct access to the neural basis of nonelemental learning. Here we asked whether colors can modulate olfactory conditioning of the proboscis extension reflex (PER) via an occasion-setting mechanism. We show that intact, harnessed bees are not capable of learning a direct association between color and sucrose. Despite this incapacity, bees solved an occasion-setting discrimination in which colors set the occasion for appropriate responding to an odor that was rewarded or nonrewarded depending on the color. We therefore provide the first controlled demonstration of bimodal (color-odor) occasion setting in harnessed honeybees, which opens the door for studying the neural basis of such bimodal, nonelemental discriminations in insects.     

Average group behavior does not represent individual behavior in classical conditioning of the honeybee

Conditioned behavior as observed during classical conditioning in a group of identically treated animals provides insights into the physiological process of learning and memory formation. However, several studies in vertebrates found a remarkable difference between the group-average behavioral performance and the behavioral characteristics of individual animals. Here, we analyzed a large number of data (1640 animals) on olfactory conditioning in the honeybee (Apis mellifera). The data acquired during absolute and differential classical conditioning differed with respect to the number of conditioning trials, the conditioned odors, the intertrial intervals, and the time of retention tests. We further investigated data in which animals were tested for spontaneous recovery from extinction. In all data sets we found that the gradually increasing group-average learning curve did not adequately represent the behavior of individual animals. Individual behavior was characterized by a rapid and stable acquisition of the conditioned response (CR), as well as by a rapid and stable cessation of the CR following unrewarded stimuli. In addition, we present and evaluate different model hypotheses on how honeybees form associations during classical conditioning by implementing a gradual learning process on the one hand and an all-or-none learning process on the other hand. In summary, our findings advise that individual behavior should be recognized as a meaningful predictor for the internal state of a honeybee--irrespective of the group-average behavioral performance.