Design and effectiveness of a computer-based continuing education program for orthodontists.

The design of computer-based continuing education for health professionals is an important consideration for Internet delivery because the size of graphic files greatly affects the speed with which information is delivered. Orthodontists who had indicated an interest in computer-based continuing education were shown via CD-ROM either a dynamic version of a computer continuing education program (with transitions and animations to liven up the content) or a plain version (identical content except that the transitions and animations were omitted). The program provided new information about superelastic arch wires for the initial stage of orthodontic treatment. For both versions, over 90% of the viewers thought the program was well done and provided useful information. Six of the orthodontists who received the dynamic version felt that the animations were distracting rather than helpful; only one who received the plain version felt that it was lifeless. A follow-up questionnaire showed that two-thirds of those who viewed the program had subsequently reviewed the performance data for the initial wire they were using and 20% had changed it, so the computer program was effective in changing clinical behavior. Those who saw the plain version also were more likely to have changed their clinical procedures. For Internet delivery of information to highly motivated professionals, it appears that transitions and animations are not necessary and may be more likely to decrease than increase the effectiveness of the teaching material.

Relationship between N1 evoked potential morphology and the perception of voicing.

Auditory evoked potential (AEP) correlates of the neural representation of stimuli along a /ga/-/ka/ and a /ba/-/pa/ continuum were examined to determine whether the voice-onset time (VOT)-related change in the N1 onset response from a single to double-peaked component is a reliable indicator of the perception of voiced and voiceless sounds. Behavioral identification results from ten subjects revealed a mean category boundary at a VOT of 46 ms for the /ga/-/ka/ continuum and at a VOT of 27.5 ms for the /ba/-/pa/ continuum. In the same subjects, electrophysiologic recordings revealed that a single N1 component was seen for stimuli with VOTs of 30 ms and less, and two components (N1' and N1) were seen for stimuli with VOTs of 40 ms and more for both continua. That is, the change in N1 morphology (from single to double-peaked) coincided with the change in perception from voiced to voiceless for stimuli from the /ba/-/pa/ continuum, but not for stimuli from the /ga/-/ka/ continuum. The results of this study show that N1 morphology does not reliably predict phonetic identification of stimuli varying in VOT. These findings also suggest that the previously reported appearance of a "double-peak" onset response in aggregate recordings from the auditory cortex does not indicate a cortical correlate of the perception of voicelessness.

Psychiatric presentations of medical illness.

Geriatric patients are subject to mental disorders that are due to the physiologic effects of medical illness or are substance induced. Elders are at increased risk for such syndromes because of the higher rates of physical illnesses and resultant polypharmacy as well as aging-related susceptibility to disruption of brain functioning. This article reviews psychiatric syndromes that are due to general medical conditions or are substance induced, focusing on the more common, acute conditions of delirium and psychotic, mood, and anxiety disorders that are due to general medical conditions. The ultimate goal of patient care must be accurate diagnosis with resultant optimal, appropriate treatment and improvement in functioning leading to the better well-being of the elderly patient.