Perceptions and Persistence: A Multifaceted Exploration of the Hypnagogic State and Unfinished Intentions

The present dissertation explores two research topics: The perceptions during the hypnagogic state and the persistence of incompleted intentions. The hypnagogic state refers to the transition between wakefulness and sleep, in which vivid perceptions can occur across all modalities. A literature review identified a lack of consensus on their definition, prevalence and characteristics. A subsequent questionnaire study assessed their prevalence, modality, and characteristics compared to other phenomena. Hypnagogic states occurred quite frequently in the population, characterized by a predominant emergence in the kinaesthetic modality. Regarding the persistence of unfinished intentions, the focus was put on the memory advantage of interrupted tasks, called the Zeigarnik effect, and the tendency to resume interrupted tasks, called the Ovsiankina effect. To investigate both effects, a meta-analytical approach was employed, with a subsequent experimental replication attempt using videogames. Results showed a general resumption tendency of unfinished intentions, but no memory advantage. Following these results, the memory advantage was investigated using anagrams. Here, a memory advantage of interrupted tasks could be observed but could not be related to the Zeigarnik effect, questioning the effect's validity. Finally, research into the phenomenology and function of the hypnagogic state seems particularly promising. Regarding unfinished intentions, research should focus on their underlying neurological mechanisms, as their resumption tendency seems apparent and their memory advantage unreplicable

Hypnagogic states are quite common: Self-reported prevalence, modalities, and gender differences.

The hypnagogic state refers to the transitional phase between wakefulness and sleep during which vivid experiences occur. In this questionnaire study, we assessed the self-reported prevalence of hypnagogic states considering the frequency of experiences in different modalities. We also assessed the emotional quality and the vividness of the experiences. Moreover, we compared hypnagogic states to other phenomena, such as dreams, sleep paralysis, imagination, and extra-sensory perception in these measures. Hypnagogic states were reported by 80.2 % of 4456 participants and were more prevalent in women than men. Experiences were most often kinaesthetic and visual, and less often auditory, tactile, and olfactory or gustatory. Hypnagogic states were less prevalent than dreams and characterized by different modality profiles. However, they were similar to dreams in their emotional quality, the irritation they caused, and in their vividness. In conclusion, hypnagogic states are quite common

Achievement Motivation Affects Memory For Unfinished Tasks

This study aimed to investigate whether achievement motivation affects memory for finished and unfinished tasks. We tested 1094 young adults, who were presented with 12 anagrams and given one minute to complete each of them. After a short delay, they had to recall as many anagrams as possible. The results showed that unsolved anagrams were more likely to be recalled than solved ones. Moreover, achievement motivation resulted in higher recall of unsolved anagrams. These findings provide support for the special status of unfinished tasks in memory and highlight the importance of achievement motivation for Zeigarnik-like phenomena

The hypnagogic state: A brief update

The hypnagogic state refers to a transitional stage between wakefulness and sleep, in which sensory perceptions can be experienced. In this review, we compile and discuss the recent scientific literature on hypnagogia research regarding the future directions proposed by Schacter (1976; Psychological Bulletin, 83, 452). After a short introduction discussing the terminology used in hypnagogia research and the differentiation of hypnagogic states with other related phenomena, we review the reported prevalence of hypnagogic states. Then, we evaluate the six future directions suggested by Schacter and we propose three further future directions. First, a better understanding of the emotional quality of hypnagogic states is needed. Second, a better understanding of why hypnagogic states occur so frequently in the visual and kinaesthetic modalities is needed. Lastly, a better understanding of the purpose of hypnagogic states is needed. In conclusion, research has made great progress in recent years, and we are one step closer to demystifying the hypnagogic state

Gamifying Intention Memory – Revisiting Ovsiankina

The Ovsiankina effect refers to the desire to complete interrupted and unfinished tasks. In this study, we investigated whether this effect can be generalized and is observable in videogames. We created 16 short videogames, which were comparable in their controls, and half of which were interrupted midway, whilst the other half could be finished. To complete the videogame, participants either had to reach a certain score or achieve the highest score possible in a finite amount of time. After playing, participants chose eight games for replay. Overall, interrupted videogames were chosen more frequently for replay than finished videogames. Thus, we showed that the Ovsiankina effect appears to be robust and observable even in videogames

Hypnagogic states are quite common: Evidence from a prevalence study with young adults.

The hypnagogic state refers to the transitional phase between wakefulness and sleep during which vivid experiences occur. There is, however, great ambiguity in the reported prevalences of this phenomenon. In this study, we assessed the prevalence of hypnagogic states and the frequency of experiences in different modalities (visual, auditory, tactile, kinaesthetic, olfactory and gustatory) in three adult samples of a total of 4457 participants. We also asked them to rate their emotional quality, how irritated they felt by their experiences, and how vivid their experiences were. Moreover, we compared hypnagogic states to other states of consciousness, such as dreams, sleep paralysis, imagination, and extra-sensory perception. Hypnagogic states occurred in up to 81.5% of participants and prevalence was comparable across samples. Experiences were most often kinaesthetic (90.3%) and visual (70.9%), and less often auditory (43.1%), tactile (38.3%), and olfactory or gustatory (24.6%). Hypnagogic states were less prevalent than dreams and expressed a different profile of modalities in which they occurred, but were comparable in their emotional quality, the irritation they caused, and their vividness. In conclusion, hypnagogic states are quite common

α_S1-casein genetic variants in Sarda goat breed

Sardinia plays an important role in Italian goat breeding; this is due not only to the high extent of its patrimony and production, but also to the fact that the main breed, the Sarda goat, represents an interesting biodiversity source. As regards the morphologic variability, marked differences between subjects reared in the coast and mountain areas were found (Macciotta et al., 2002). These differences are due to the genetic selection on the autochthonous patrimony, set up by breeders and based on coat colour, horn presence and/or on functional criteria (udder shape). The need to improve milk yields also induced various breeders, mainly in those areas with better pasture conditions, to crossbreed the Sarda goats with more productive breeds. The present situation (Pazzola et al., 2002) shows how in the East coastal region (Sarrabus, Ogliastra and Baronia) and in the central mountain areas of Sardinia (Barbagia), subjects with more rural traits are reared (smaller size, small ears, presence of horns, etc.); while in the South and West areas (Sulcis and Guspinese) the influence of the Maltese breed is more evident. Both the productive traits variability (Brandano et al., 1978), and the morphologic aspect, is of great interest. Genetic variability can influence the survival of a sector hindered by the opening of the markets and by the strong competitiveness of zootechnical areas technologically more advanced. According to this point of view, considering that casein fractions are closely related to milk technological characteristics (Grosclaude et al., 1994), and to its possible productive differentiation (Remeuf, 1993), a study on αS1-casein allelic frequency was carried out, related also to the breeding region. The aim of the study is to acquire useful information in order to suggest an appropriate utilization of milk, to detect possible new alleles and to test the correlation between casein phenotype and morphology of the animals

In vivo and in vitro methods to determine biliary clearance of drugs in humans

Biliary excretion is an important route of hepatic elimination of drugs and metabolites that is investigated commonly using in vitro or in vivo animal models. However, changes in biliary clearance due to drug-drug interactions, genetic polymorphisms and/or disease state may be species-specific, and animal data may be difficult to extrapolate to humans. This dissertation research focused on the development and refinement of a specialized clinical protocol and novel oroenteric tube to accurately quantify biliary clearance of drugs in humans and the comparison of these values with predicted biliary clearance values determined in sandwich-cultured human hepatocytes. Hepatocytes cultured between two layers of extracellular matrix express and correctly localize functional transport proteins on the canalicular as well as the basolateral domains, and enable determination of drug excretion into bile by quantifying accumulation within the hepatocyte and bile canalicular networks. Experiments were devised and performed to establish the utility of this model to predict hepatobiliary drug disposition in humans. The biliary clearance of three model probes, Tc-99m mebrofenin, Tc-99m sestamibi, and piperacillin, was evaluated in healthy humans. These model compounds exhibited high, intermediate and low biliary clearance, respectively. Pharmacokinetic modeling and simulations of the disposition of Tc-99m mebrofenin in humans, combined with results of in vitro systems transfected with hepatic transport proteins, revealed that disease states and drug interactions would impact the hepatobiliary disposition of this probe. Moreover, the recovery of piperacillin metabolites in bile samples obtained during the clinical studies suggested that the clinical methodology developed is useful for the identification of metabolites unique to the human species. Finally, the biliary clearance values obtained in vivo were compared to those calculated using sandwich-cultured human hepatocytes. The in vitro system proved to be a reliable model for predicting biliary clearance of xenobiotics in humans. Collectively, the results of this research provide new tools, both in vivo and in vitro, to study and characterize biliary clearance of drugs in the most relevant species, humans