Emilie Lacroix

Tinnitus specifically alters the top-down executive control sub-component of attention: Evidence from the Attention Network Task.

Tinnitus can be defined as the perception of noxious disabling internal sounds in the absence of external stimulation. While most individuals with tinnitus show some habituation to these internal sounds, many of them experience significant daily life impairments. There is now convincing evidence that impairment in attentional processes may be involved in tinnitus, particularly by hampering the habituation mechanism related to the prefrontal cortex activity. However, it is thus still unclear whether this deficit is an alteration of alerting and orienting attentional abilities, or the consequence of more general alteration in the executive control of attention. In the present study, 20 tinnitus patients were compared to 20 matched healthy controls using the Attention Network Test, to clarify which attentional networks, among alerting, orienting, and executive networks, show differences between the groups. The results showed that patients with tinnitus do not present a general attentional deficit but rather a specific deficit for top-down executive control of attention. This deficit was highly correlated with patient characteristics of years of tinnitus duration and the frequency of coping strategies employed to alleviate tinnitus distress in daily life. These findings are discussed in terms of recent neurobiological models suggesting that prefrontal cortex activity might especially be related to tinnitus habituation. Therapeutic perspectives focusing both on rehabilitation of the executive control of attention and neuromodulation are also discussed.

Altered top-down cognitive control and auditory processing in tinnitus: evidences from auditory and visual spatial stroop

PURPOSE Tinnitus is the perception of a sound in the absence of external stimulus. Currently, the pathophysiology of tinnitus is not fully understood, but recent studies indicate that alterations in the brain involve non-auditory areas, including the prefrontal cortex. Here, we hypothesize that these brain alterations affect top-down cognitive control mechanisms that play a role in the regulation of sensations, emotions and attention resources. METHODS The efficiency of the executive control as well as simple reaction speed and processing speed were evaluated in tinnitus participants (TP) and matched control subjects (CS) in both the auditory and the visual modalities using a spatial Stroop paradigm. RESULTS TP were slower and less accurate than CS during both the auditory and the visual spatial Stroop tasks, while simple reaction speed and stimulus processing speed were affected in TP in the auditory modality only. CONCLUSIONS Tinnitus is associated both with modality-specific deficits along the auditory processing system and an impairment of cognitive control mechanisms that are involved both in vision and audition (i.e. that are supra-modal). We postulate that this deficit in the top-down cognitive control is a key-factor in the development and maintenance of tinnitus and may also explain some of the cognitive difficulties reported by tinnitus sufferers.

The development of a new questionnaire for cognitive complaints in vertigo: the Neuropsychological Vertigo Inventory (NVI)

Vertigo patients frequently complain of emotional and associated cognitive problems, yet currently, there is no satisfactory questionnaire to measure these associated problems. In the present paper, we propose a new internet-based Neuropsychological Vertigo Inventory (NVI; French) that evaluates attention, memory, emotion, space perception, time perception, vision, and motor abilities. The questionnaire was created using four steps: (1) open interviews with patients suffering from vertigo; (2) semi-structured interviews with an analysis grid to quantify and define the various cognitive and emotional problems reported by the patients; (3) a first version of an internet questionnaire tested on 108 vertigo participants; and (4) the selection of subscale items using principal component analyses (PCA). From the development phase, the revised NVI was composed of seven subscales, each with four items (28 items). In the validation phase, Cronbach’s alphas were performed on the revised NVI for total and each subscale score, and to test extreme groups validity, the analyses of covariance (ANCOVAs) taking into account age were performed between 108 vertigo and 104 non-vertigo participants. The Cronbach’s alphas showed good to satisfactory coefficients for the total and for all subscale scores, demonstrating acceptable reliability. The extreme groups validity analyses (ANCOVAs) were reliable for the total scale and for four subscales. Supplementary analyses showed no effect of hearing difficulties and an inverse age effect for attention and emotion subscales, with reduced problems with increased age in the vertigo participants. The NVI provides a useful new questionnaire to determine cognitive and emotional neuropsychological complaints that are associated with vertigo.