Priming performance in Alzheimer's disease: the role of task sensitivity.

Studies examining implicit memory performance in Alzheimer's disease (AD) have yielded inconsistent findings, with these patients demonstrating impaired performance within some priming studies and intact performance within others. The present study examined the role of task sensitivity in detecting impaired priming in memory-impaired patients. Twelve healthy older adults and 12 AD patients were administered a picture fragment identification test. Task sensitivity was increased by employing stimulus cues expected to produce larger and more variable priming effects than obtained in previous studies. A simple comparison of priming scores revealed that the AD patients demonstrated significantly impaired priming relative to normal control participants. However, further analysis of priming in relation to certain stimulus characteristics revealed that AD patients often demonstrated impaired priming when overall priming effects were large but relatively intact priming when priming effects were small. These findings suggest that the prevention of ceiling effects in control participants may aid in the detection of impaired priming in patient populations.

The impact of behavioral symptoms on activities of daily living in patients with dementia.

The authors examined whether scores on two recently developed measures of behavioral disturbance, the Frontal Lobe Personality Scale (FLOPS) and the Neuropsychiatric Inventory (NPI), are associated with functional impairments in patients with dementia. Caregivers of 30 dementia patients were administered the FLOPS Family Form, the NPI, and an Activities of Daily Living (ADL) scale. Findings indicated a relationship between behavioral changes and functional limitations in patients with dementia. Moreover, the FLOPS, an instrument designed to specifically measure behaviors subserved by frontal lobe systems, was more strongly related to failures in instrumental ADLs than was the NPI. The authors conclude that behavioral measures add information over and above that available from cognitive tests in determining ADL functioning.

Deterioration of generic knowledge in patients with Alzheimer's disease: evidence from the Number Information Test.

Semantic memory for generic knowledge was assessed in patients with probable Alzheimer's disease (AD; n = 142) and elderly normal control (NC; n = 78) subjects using the Number Information Test (NIT), a test that consists of 24 general knowledge questions that require a single number for an answer (e.g., "How many days are in a year?"). The results showed that patients with AD were impaired, even in the mildest stage of dementia, and that this impairment grew as the severity of their dementia increased over time. In addition, patients with AD were highly consistent in the individual items they missed in subsequent test sessions conducted 1 or 2 years later. These results indicate that semantic memory for generic knowledge is impaired relatively early in AD, deteriorates throughout the course of the disease, and may be due to a loss of knowledge rather than to a retrieval deficit.

Two cases of death involving dicyclomine in infants. Measurement of therapeutic and toxic concentrations in blood.

In two deaths of infants investigated by the Medical Examiner, high levels of dicyclomine were detected in blood. In one of the cases, a level of 0.505 micrograms/ml was found, nearly 10 times reported adult therapeutic blood concentrations, and death was ascribed to an overdose of dicyclomine. Gas chromatography/mass spectrometry was used for the analysis of biological specimens.

Detection of marihuana use by GC/MS analysis of mouth swabs.

A relatively simple and rapid test for detection of the components of Cannabis sativa (marihuana) after smoking consists of swabbing the exposed areas with an alcohol-containing swab, then concentrating the extract from the swab for direct analysis by Gas Chromatography-Mass Spectrometry. This test is now performed in several medical examiner's offices. This study was performed to evaluate this test using volunteer marihuana-smoking subjects. Caution must be used in interpreting the results obtained because of the transient nature of the intoxication, and because of the possibility of obtaining false-positive results. The time response and other parameters concerning the procedure are also discussed.

Drug detection at autopsy: a prospective study of 247 cases.

Comprehensive toxicology analyses using gas chromatography of blood for alcohol and acidic, basic, and neutral drugs were performed on 247 randomly selected medical examiner cases. Drugs or alcohol or both were found in 54% of this group. When considered by manner of death (natural, accident, homicide, and suicide), each of the groups had incidences of positive findings of 46 to 63%. Selection of cases for toxicologic study on the basis of manner of death does not seem to be feasible. It is the authors' opinion that comprehensive toxicology evaluation for drugs should be done on virtually all medical examiner cases. This approach ensures a thorough and complete evaluation in all cases. In addition, a comprehensive toxicology study will provide information in the event that questions concerning the absence or presence of drugs arise at some later date.

Suicide by snake venom injection.

A case of apparent suicide by injection of snake venom was investigated. Evidence found at the scene and presumably used for self-injection was positive for nonspecific venom but had the characteristics of a viper venom.

Spontaneous pneumothorax in the newborn: a report of two fatalities.

Spontaneous pneumothorax is present in 1 to 2% of healthy full-term newborn infants. Virtually all cases have resolution of the pneumothorax without sequelae and in fact without the condition being diagnosed. Two fatal cases are presented. Anyone doing medicolegal autopsies should be aware of this entity so that X-rays or other appropriate methods to demonstrate it can be used.