Laurence R. Hartley

Aberrant driving behaviour: errors and violations

The present study was a replication of the research of Reason et al. (1990). Its aim was to confirm the distinction between driving errors and violations in a Western Australian driving population. Sixty-one male drivers and 74 female drivers completed a questionnaire containing items on driver demographics, driving penalties incurred, driving convictions and accident history and driver behavioral aberrations drawn from the Driver Behaviour Questionnaire (DBQ). In agreement with Reason et al. factor analysis revealed three factors; in the present study these were general errors, dangerous errors, and dangerous violations. Young drivers committed more dangerous errors and dangerous violations than older drivers. Females reported more dangerous errors than males. Males reported more dangerous violations than females. Drivers who reported a high level of road exposure and those who reported having been convicted for speeding reported more dangerous violations. Differences in the results of the two studies can largely by accounted for by differences in the representation of age and gender in the two populations studied.

Fatigue risk management: Organizational factors at the regulatory and industry/company level

This paper focuses on the development of fatigue risk management systems (FRMS) in the transport sector. The evolution of regulatory frameworks is traced, from uni-dimensional hours of service regulations through to frameworks that enable multi-dimensional FRMS. These regulatory changes reflect advances in understanding of human error in the aetiology of accidents, and in fatigue and safety science. Implementation of FRMS shifts the locus of responsibility for safety away from the regulator towards companies and individuals, and requires changes in traditional roles. Organizational, ethnic, and national culture need to be considered. Recent trends in the work environment have potential to adversely affect FRMS, including precarious employment and shortages of skilled labour. Essential components of an FRMS, and examples of FRMS in different transport modes, are described. It is vital that regulators, employer, and employees have an understanding of the causes and consequences of fatigue that is sufficient for them to meet their responsibilities in relation to FRMS. While there is a strong evidence base supporting the principles of FRMS, experience with implementation is more limited. The evidence base for effective implementation will expand, since FRMS is data-driven, and ongoing evaluation is integral. We strongly advocate that experience be shared wherever possible.

The effects of scopolamine upon verbal memory: evidence for an attentional hypothesis

Immediate and delayed free recall and recognition of dichotically presented lists of nouns were assessed in a group of normal female volunteers following oral administration of either a placebo or 0.6 mg scopolamine hydrobromide. Results show that, while there was no drug effect upon total (i.e., attended plus unattended) recall, there was a significant drug by attention interaction, in that recall for attended words was impaired while unattended recall was facilitated. There were no drug effects upon recognition performance. It was concluded that scopolamine acts to modulate selective attention rather than memory consolidation processes, and it is suggested that the cholinergic system may be centrally involved in the control of effortful or intentional processing in memory.

Indicators of fatigue in truck drivers

This study examined physiological and psychological changes in one solo truck driver and both drivers in a two-up truck crew during several 5-6 day round-trips to the north west of Western Australia. Endocrine catecholamine levels, cardiac sinus arrhythmia and serial reaction performance all showed progressive changes over the journey. The solo driver showed greater changes on most measures than the two-up crew and compared with control measures obtained from research assistants accompanying the drivers. The results suggest that solo drivers may experience more fatigue, impaired capacity for controlled mental effort and slowed reactions than a two-up crew.

The effects of nicotine upon memory and problem solving performance

This study examined the effects of 4 mg nicotine and placebo upon problem solving performance in word and number tasks, and subsequent recall and recognition of the answers to these problems. The results demonstrated that the drug had no effect upon the subjects ability to generate the correct answers to the problems, but that immediate and delayed recall and recognition were significantly impaired. These data clearly do not support the view that nicotine, without exception, enhances information processing, and it was suggested that the effects of nicotine upon information retrieval may be specific to tasks which assess episodic memory in the absence of retrieval cues or a problem solving context.

Patterns of stimulant drug use on Western Australian heavy transport routes

In July 1997, 236 truck drivers were interviewed at three truck stops in Western Australia. The interviews collected information on driver fatigue and stimulant drug taking as a fatigue countermeasure. Drivers have become more aware of fatigue as a problem within the industry over the past two years, however, 27% of drivers reported using stimulant drugs to combat driver fatigue. Interstate drivers use more prescription and illicit stimulant drugs to keep awake while intrastate drivers use more over the counter stimulants. Over the counter stimulants are not perceived as drugs by intrastate drivers because they are easily and legally obtainable and this is reflected within many of their responses. The most frequent way that drivers obtained stimulant drugs was through a doctor, a chemist or illegal prescription. Anecdotal evidence from the drivers suggests that increasing pressure from the public and the media to eliminate illegally prescribed stimulant use by drivers has made them harder to obtain. Therefore, without fatigue issues within the industry being addressed, an increase in street purchases of illicit stimulants may occur. Prohibition of stimulant drug use without changing industry practices eliminates a fatigue countermeasure and could lead to a serious increase in fatigue-related crashes. The results of this study will help to identify “at risk” groups of drivers who can be targeted for education on fatigue and drug issues.

Memory and menstrual cycle

Thirty women with regular menstrual cycles were tested on immediate and delayed verbal retention, immediate memory for acoustically and semantically confusing word lists, and verbal reasoning. The Menstrual Distress Questionnaire (MDQ) was also administered. Testing was carried out at three phases of the menstrual cycle: ovulation, menstruation and the premenstrual phase. Immediate and delayed recall showed no differences across the three phases. Speed of verbal reasoning was found to be slower on more complex sentences during ovulation. Recall of semantically similar lists was impaired in ovulation, while recall of acoustically similar lists tended to be impaired in paramenstrum. There was a significant interaction between phases and list types. On the MDQ self-reported arousal was higher in ovulation, whereas distress was higher in the premenstrual phase, although this appears to be unrelated to the performance changes. The practical implication of these performance changes for the verbal processing of ...

Speed choice by drivers: The issue of driving too slowly

Quite correctly, the majority of road safety speeding initiatives focus on drivers travelling at excessive speeds. This study, however, focused on the potential problem of driving too slowly. Six thousand, four hundred and eighty vehicles from around the Perth metropolitan area in Western Australia had their speeds recorded; observations were also made of these vehicles to identify characteristics of the driver and vehicle. In addition, a community survey with 240 members of the public was conducted to examine their attitudes towards slow drivers. As expected, results showed that older drivers drove more slowly than the other age brackets, women drove more slowly than men, and that heavily laden vehicles drove more slowly than other types of vehicles. Additionally, the slowest days were weekdays and the quickest were Saturdays. Community attitudes, generally mirrored the observational findings, and indicated that the public believed that slow driving was sometimes a safety problem causing some accidents. These data are discussed, and some possible countermeasures are briefly introduced to address the problem.

Anxiety, diazepam and retrieval from semantic memory

Diazepam, an anxiolytic, was administered to 16 undergraduate volunteers in a double-blind design. Eight subjects were selected to be high in State and Trait anxiety and were slow in recall on a semantic memory task compared to non-anxious subjects. Instead of alleviating this detrimental effect of anxiety on memory, diazepam slowed recall in both the anxious and non-anxious.

Chlorpromazine and the lateralisation of the perception of emotion.

In a double-blind design, sixteen volunteer students were administered 50 mg of chlorpromazine or a placebo in tablet form on separate occasions, two hours prior to testing. The test was a lexical decision paradigm involving unilateral presentation of pairs of neutral, positive and negative emotional words and nonwords to the left or right visual fields. Reaction time to identify words and nonwords was recorded. Neutral stimuli were processed faster in the left hemisphere, while negative stimuli were processed faster in the right hemisphere. Chlorpromazine improved speed of response for neutral stimuli presented to the right hemisphere and for affective stimuli presented to the left hemisphere. Thus chlorpromazine seems to benefit right hemisphere processing of nonaffective stimuli and benefit left hemisphere processing of affective stimuli. Chlorpromazine appeared to have a different impact on neutral and affective words, and on the right and the left hemispheres. The general effect of chlorpromazine was to reduce lateralisation. It was suggested that this occurred because chlorpromazine blocked dopamine and possibly other neurotransmitters.