Olfactory Dysfunction in Sports Players following Moderate and Severe Head Injury: A Possible Cut- off from Normality to Pathology

ABSTRACT Concussion occurs with some frequency in a variety of sports. Any trauma to the brain can also result in temporary or chronic olfactory dysfunction. The relationship between sports concussion and olfactory dysfunction is not well studied, nor do we know whether only more severe injuries result in smell impairments. Three sports players who had previously experienced either a moderate or severe concussion were compared to matched controls. Only the player with a previous severe concussion had a current olfactory impairment. We tentatively suggest that the distinction between moderate and severe concussion may represent a possible cut-off between the presence and absence of olfactory impairment in sports players

Cognition and Olfaction: A Review

Examines research in cognitive psychology, which has in the past paid little attention to the olfactory modality. But there is now a significant body of literature on the role of the olfactory system in memory and cognition. Human beings possess an excellent ability to detect and discriminate odors, but they typically have great difficulty in identifying particular odorants. This results partly from the use of an impoverished and idiosyncratic language to describe olfactory experiences, which are normally encoded either in a rudimentary sensory form or as part of a complex but highly specific biographical episode. Consequently, linguistic processes play only a very limited role in olfactory processing, whereas hedonic factors seem to be of considerable importance

UNCONSCIOUS ODOUR CONDITIONING 25 YEARS LATER: REVISITING AND EXTENDING 'KIRK-SMITH VAN TOLLER AND DODD'.

The pioneering work by Kirk-Smith, Van Toller, and Dodd [Kirk- Smith, M. D., Van Toller, C., & Dodd, G. H. (1983). Unconscious odour conditioning in human subjects. Biological Psychology, 17, 221\u2013231], established that an unnoticed odorant paired with an emotionally meaningful task can influence mood and attitudes when the odorant alone is re-encountered subsequently. This study was particularly important in highlighting unconscious odour learning processes as they may happen in everyday life. However, it was severely criticized by Black and Smith [Black, S. L., & Smith, D. G. (1994). Has odor conditioning been demonstrated? A critique of \u2018\u2018Unconscious odour conditioning in human subjects\u201d. Biological Psychology, 37, 265\u2013267] on methodological grounds. In the present paper, we replicated and extended Kirk- Smith et al.\u2019s investigation taking into account Black and Smith\u2019s criticisms and carrying out additional controls to improve the validity of the study. The results confirm the initial findings of Kirk-Smith and colleagues by demonstrating the effectiveness of olfactory stimuli in inducing conditioned hedonic reactions even when presented below the level of awareness

Multiple Chemical Sensitivity.

Multiple Chemical Sensitivity (MCS), a condition also known as Chemical Sensitivity (CS), Chemical Intolerance (CI), Idiopathic Environmental Illness (IEI) and Toxicant Induced Loss of Tolerance (TILT), is an acquired multifactorial syndrome characterized by a recurrent set of debilitating symptoms. The symptoms of this controversial disorder are reported to be induced by environmental chemicals at doses far below those usually harmful to most persons. They involve a large spectrum of organ systems and typically disappear when the environmental chemicals are removed. However, no clear link has emerged among self-reported MCS symptoms and widely accepted objective measures of physiological dysfunction, and no clear dose-response relationship between exposure and symptom reactions has been observed. In addition, the underlying etiology and pathogenic processes of the disorder remain unknown and disputed, although biologic and psychologic hypotheses abound. It is currently debated whether MCS should be considered a clinical entity at all. Nevertheless, in the last few decades MCS has received considerable scientific and governmental attention in light of the many persons reporting this illness. In this review, we provide a general overview of the history, definition, demographics, prevalence, and etiologic challenges in defining and understanding MCS

Unconscious odour conditioning 25 years later: Revisiting and extending ‘Kirk-Smith, Van Toller and Dodd’

International audienceThe pioneering work by Kirk-Smith, Van Toller, and Dodd [Kirk-Smith, M. D., Van Toller, C., & Dodd, G. H. (1983). Unconscious odour conditioning in human subjects. Biological Psychology, 17, 221–231], established that an unnoticed odorant paired with an emotionally meaningful task can influence mood and attitudes when the odorant alone is re-encountered subsequently. This study was particularly important in highlighting unconscious odour learning processes as they may happen in everyday life. However, it was severely criticized by Black and Smith [Black, S. L., & Smith, D. G. (1994). Has odor conditioning been demonstrated? A critique of “Unconscious odour conditioning in human subjects”. Biological Psychology, 37, 265–267] on methodological grounds. In the present paper, we replicated and extended Kirk-Smith et al.’s investigation taking into account Black and Smith’s criticisms and carrying out additional controls to improve the validity of the study. The results confirm the initial findings of Kirk-Smith and colleagues by demonstrating the effectiveness of olfactory stimuli in inducing conditioned hedonic reactions even when presented below the level of awareness

From blindsight to blindsmell: a mini review

This mini-review briefly documents the phenomenon of blindsight and investigates evidence for a comparable state in olfaction. Blindsight evokes an appropriate response to a visual stimulus without any conscious visual experience or awareness of that event. For olfaction, we describe many routine aspects of perception that may occur without conscious awareness, arguably paralleling key aspects of blindsight. We then describe the limited neuropsychological evidence suggesting that people can apparently respond appropriately to odours that they cannot subjectively smell – what we would term “blindsmell”

Olfactory asymmetric dysfunction in early Parkinson patients affected by unilateral disorder

Introduction: Parkinson’s disease (PD) often first presents with asymmetric motor symptoms. A number of studies have now established that sensory deficits can also be similarly asymmetric. It is well established that PD is associated with marked olfactory dysfunction, but whether this too present asymmetrically is a currently contentious question. Methods: To address this, we recruited 12 early stage Parkinson patients with right-sided motor symptoms and compared them to 12 healthy age-matched controls on tests of olfactory identification and recognition, administered separately to each nostril. Results: Data analyses indicated that Parkinson patients performed worse with the left nostril on both tasks, while no nostril-related differences were observed for the healthy age-matched control group on the same comparisons. Conclusion: These findings support the idea that asymmetric deficits do extend into olfactory performance in PD—as they do into other sensory domains—and we examine the possibility that they might be a particular feature of right-sided motor symptom presentation.4 page(s

Olfactory Dysfunction in Sports Players following Moderate and Severe Head Injury: A Possible Cut-off from Normality to Pathology

Concussion occurs with some frequency in a variety of sports. Any trauma to the brain can also result in temporary or chronic olfactory dysfunction. The relationship between sports concussion and olfactory dysfunction is not well studied, nor do we know whether only more severe injuries result in smell impairments. Three sports players who had previously experienced either a moderate or severe concussion were compared to matched controls. Only the player with a previous severe concussion had a current olfactory impairment. We tentatively suggest that the distinction between moderate and severe concussion may represent a possible cut-off between the presence and absence of olfactory impairment in sports players

Applied Olfactory Cognition

Foreword by Richard J. Stevenson, Macquarie University (Australia): It was long thought that the human nose might be able to discriminate somewhere in the order of 10,000 different odourants. The recent finding that the human nose can discriminate something like a trillion different smells serves as yet another reminder that we have again underestimated the capacity of our sense of smell (Bushdid, Magnasco, Vosshall & Keller, 2014). This volume serves as a further corrective for anyone who should hold the view that olfaction is unimportant in human affairs. The papers presented in this ebook, carefully collated and overseen by Aldo Zucco, Benoist Schaal, Mats Olsson and Ilona Croy, showcase a large number of quite different reasons for studying the applied side of olfaction, and indeed human olfaction in general. The 23 contributions presented here cover a broad range of topics, which illustrate contemporary interests in our field. Although with a strong applied focus, a noteworthy feature of this ebook is the richness of the theoretical perspectives that are developed. These range from considerations of olfactory perception, memory, expertise, and priming right the way through to receptor genetics. These contributions, from many leading experts in the field, will surely shape much of the applied work linking olfaction to disease, which is a further focus of this ebook. In respect to health and disease, the chapters on aging, pregnancy, depression, alcohol dependency and environmental odours, present overviews and rich new data on many contemporary problems, to which the study of olfaction is now contributing. A particularly notable aspect of olfactory experience is the affective impact that odours can have on people and their lives. The ebook covers some particularly intriguing aspects of work in this area, with empirical studies investigating dissociations between wanting and liking, stress reduction in the elderly, mother-infant bonding, and the emotions that different odourants can evoke. This affective line of work is nicely complemented by empirical studies on expertise, the effect of odours on visual attention, and the relationship between particular personality traits and interest in olfaction. The gradual appropriation of methods from cognitive neuroscience into olfaction is also nicely represented in this ebook, with at least three of the chapters reporting data using neuroimaging, including a particular intriguing study looking at recognition of odours in mixtures. Finally, the close links between olfactory perception and sensory evaluation are also reflected in a chapter on wine. I hope that readers of this e-book will be struck, as I have been in reading its various chapters, how much olfaction affects our lives, and how the study of this sense can enrich it