Dimosthenis Pavlou

Incidental and Intentional Memory: Their Relation with Attention and Executive Functions

Objective The aim of the current study was to investigate the impact of gender and age on incidental and intentional memory in healthy participants and to explore the strength of the association of incidental and intentional memory with attentional and executive functioning. Method A total number of 47 participants underwent a driving simulation experiment and went through detailed neuropsychological testing. Incidental memory was assessed with a questionnaire that evaluated the memorization of information related to the driving simulator task while intentional memory was assessed using the Hopkins Verbal Learning Test-Revised and the Brief Visuospatial Memory Test-Revised. Results The analysis revealed a greater impact of age on incidental as compared to intentional memory. Gender did not appear to have such an effect on either incidental or intentional memory. Finally, attentional and executive functioning were more strongly associated with incidental memory than the intentional memory measures that were utilized in the current study. Conclusions Ageing appears to affect incidental rather than intentional memory to a greater extent. In addition, attentional and executive functioning seem to play a more important role in incidental than intentional encoding and consolidation processes.

Which factors affect accident probability at unexpected incidents? A structural equation model approach

ABSTRACT Considering that unexpected events are a major contributory factor of road accidents the main objective of this article is to investigate the effect of several parameters including overall driving performance, distraction sources, driver characteristics, as well as road and traffic environment on accident probability at unexpected incidents. For this purpose, a driving simulator experiment was carried out, in which 95 participants from all age groups were asked to drive under different types of distraction (no distraction, conversation with passenger, cell phone use) in different road and traffic conditions. Then, in the framework of the statistical analysis, driving performance is estimated as a new unobserved (latent) variable based on several individual driving simulator parameters while a structural equation model is developed investigating which factors lead to increased accident probability at unexpected incidents. Regarding driver distraction, results indicate that cell phone use has a negative effect on accident risk confirming the initial hypothesis that when talking on the cell phone drivers find it difficult to handle an unexpected incident and as a result are more likely to commit an accident. Overall, a risky driving profile is developed, completing the puzzle of the effect of driver distraction on driver behavior and road safety.

Driving in mild cognitive impairment: The role of depressive symptoms

ABSTRACT Objectives: Previous studies indicate a negative association between depression and driving fitness in the general population. Our goal was to cover a gap in the literature and to explore the link between depressive symptoms and driving behavior in individuals with mild cognitive impairment (MCI) through the use of a driving simulator experiment. Methods: Twenty-four individuals with MCI (mean age = 67.42, SD = 7.13) and 23 cognitively healthy individuals (mean age = 65.13, SD = 7.21) were introduced in the study. A valid driving license and regular car use served as main inclusion criteria. Data collection included a neurological/neuropsychological assessment and a driving simulator evaluation. Depressive symptomatology was assessed with the Patient Health Questionnaire (PHQ-9). Results: Significant interaction effects indicating a greater negative impact of depressive symptoms in drivers with MCI than in cognitively healthy drivers were observed in the case of various driving indexes, namely, average speed, accident risk, side bar hits, headway distance, headway distance variation, and lateral position variation. The associations between depressive symptoms and driving behavior remained significant after controlling for daytime sleepiness and cognition. Conclusions: Depressive symptoms could be a factor explaining why certain patients with MCI present altered driving skills. Therefore, interventions for treating the depressive symptoms of individuals with MCI could prove to be beneficial regarding their driving performance.

SELF-EVALUATION OF DRIVING ABILITY THROUGH A DRIVING SIMULATOR EXPERIMENT: DIFFERENCES BETWEEN PATIENTS WITH MILD COGNITIVE IMPAIRMENT (MCI) AND HEALTHY ELDERLY DRIVERS

assumed without an adequate analysis, especially in Old Adults (OA). Among the “weak” stationarity tests, the Priestley-Subba Rao (PSR) test calculates a “local” spectra that is “valid” only for punctual moments in time. A series of “smoothed” frequency filters give information of the time the local spectra is calculated. In here, weak REM sleep stationarity by the PSR test was compared to that from Wakefulness (W) and Non-REM (NREM) sleep. Methods: 8 Old Adults (OA) (age: 67.6 6 5.7; education: 8.8 6 2.6) without depression neither anxiety and with intact daily living activities were selected. Also, evaluations with the Mini-Mental State Examination (MMSE, 28.1 6 1.8) and a one night polysomnography were performed. 30 second epochs were classified according to the AASM and every epoch of W, NREM and REM sleep was subjected to PSR tests. Percentages of stationary epochs were obtained with respect to the total number of epochs of each stage and Student t-tests were used to compare them. Results: The PSR effectively showed different proportions of stationarity according to the classification of stages in each subject. In Figure 1, in one OA, epochs with stationarity are shown in black and the classification of REM sleep is shown in green. Clearly, a lower proportion of stationarity was found in REM sleep vs the other stages. These differences reached significance in F7, Fp2, LOG and ROG (p < 0.05, Figure 2). Conclusions: In OA, REM sleep showed lower proportions of epochs with stationarity vs. W and NREM sleep at anterior areas, a result that could be explained by the tonic and phasic REM sleep. When stationarity measurements are planned, it is recommended to differentiate anterior from lateral and posterior areas.

670 Exploration of accident probability of drivers with brain pathologies

Background Despite the fact that road traffic casualties presented a decreasing trend during the last years, the number of fatalities in road accidents is still unacceptable and illustrates the need for greater efforts with respect to better driving performance and increased road safety. The objective of this paper is to investigate the accident probability of drivers with cognitive impairments (Alzheimer’s Disease-AD, Parkinson’s disease-PD and Mild Cognitive Impairment-MCI) through a large driving simulator experiment. Methods A full neurological and neuropsychological assessment was carried out and then a driving simulator experiment was applied. The driving tasks included driving in urban and rural road, at moderate and high traffic volumes, with and without distraction (conversation with passenger and conversation through mobile phone), while various unexpected incidents were scheduled to occur (sudden appearance of an animal on the roadway, or sudden appearance of a child chasing a ball or a car suddenly getting out of a parking position and getting in the road in urban area). Results The sample scheme consisted of 140 participants of similar demographics: 31 healthy controls, 25 AD, 59 MCI, and 25 PD patients. The accident probability was analysed, by descriptive statistics at first and then appropriate mathematical models were developed. Results indicated that patients were more likely to crash the incident that unexpectedly happened. The accident risk of AD and MCI drivers was 30% higher than the control group. Finally, the negative impact of use of the mobile phone, regarding accident probability, was more significant on the patients. Conclusions The patients had systematically higher accident probability than the cognitively intact individuals, in the majority of driving conditions. These results could have considerable practical importance as they provide useful information about the formulation of efficient countermeasures.