Music shifts frontal EEG in depressed adolescents.

Recent studies have found that positive affect is associated with greater relative left frontal EEG activation and negative affect is associated with greater relative right frontal EEG activation. Further, chronically depressed adults typically display stable right frontal EEG activation. The present study investigated the effects of music on mood state and right frontal EEG activation associated with chronic depression. Fourteen chronically depressed female adolescents listened to rock music for a 23-minute session. These adolescents were compared with a control sample of chronically depressed female adolescents who were simply asked to sit and relax their minds and their muscles for the same time period. EEG was recorded during baseline, music, and postmusic for three minutes each, and saliva samples were collected before and after the session to determine the effects of the music on stress hormone (cortisol) levels. No group differences or changes were noted for observed or reported mood state. However, cortisol levels decreased and relative right frontal activation was significantly attenuated during and after the music procedure. It was concluded that music had positive effects on the physiological and biochemical measures even though observed and self-reported mood did not change.

Massage therapy reduces anxiety and enhances EEG pattern of alertness and math computations.

Twenty-six adults were given a chair massage and 24 control group adults were asked to relax in the massage chair for 15 minutes, two times per week for five weeks. On the first and last days of the study they were monitored for EEG, before, during and after the sessions. In addition, before and after the sessions they performed math computations, they completed POMS Depression and State Anxiety Scales and they provided a saliva sample for cortisol. At the beginning of the sessions they completed Life Events, Job Stress and Chronic POMS Depression Scales. Group by repeated measures and post hoc analyses revealed the following: 1) frontal delta power increased for both groups, suggesting relaxation; 2) the massage group showed decreased frontal alpha and beta power (suggesting enhanced alertness); while the control group showed increased alpha and beta power; 3) the massage group showed increased speed and accuracy on math computations while the control group did not change; 4) anxiety levels were lower following the massage but not the control sessions, although mood state was less depressed following both the massage and control sessions; 5) salivary cortisol levels were lower following the massage but not the control sessions but only on the first day; and 6) at the end of the 5 week period depression scores were lower for both groups but job stress score were lower only for the massage group.

The effect of a pulsed magnetic field and that of methyl-silane triol on galactosamine induced hepatitis among rats.

Liver cell necrosis was induced in rats by a galactosamine injection. Cell death was due to an increase of Ca++ intracellular levels and was also under the control of genes. Rats were then either exposed or not to a 6 mT 100 HZ pulsed magnetic field (PMF) and they either received or not methylsilane-triol injections. Animals were sacrificed twenty-seven hours after a galactosamine injection. On the one hand it appeared from transaminase levels that the PMF increased the number of animals which were sensitized to galactosamine but decreased transaminase levels. On the other hand PMF decreased the protective effect of MST against galactosamine. We may suggest that PMF should be considered as an additional cellular signal received through genes which would determine the evolution towards or against apoptosis according to the age of the cell itself but also the Ca++ intracellular level.

Retention interval and intertrial interval in a serial learning or delayed discrimination task.

In each of four experiments, rats were provided with the same three-event decreasing series (18-1-0) of 0.045-g food pellets in a runway. Tracking, running fast to 18 pellets and running slow to 1 and 0 pellets, was investigated as a function of the temporal interval elapsing between the events of the series (the retention interval), shifts in retention interval, and number of trials each day (or the intertrial interval), a trial being defined as presentation of each of the three events of the series. Neither retention interval, which varied from 15 s to 30 min in various investigations, nor shifts in retention interval affected tracking when only one trial was given each day. But when more than one daily trial was given, tracking was acquired more slowly and was disrupted by a shift in retention interval from 15 s to 5 min. Tracking was also disrupted by a shift from one to two trials each day. These results indicate that when given one 18-1-0 trial each day, the rat partitions events on a first-event/subsequent-event basis; that little forgetting occurs even at long retention intervals; that somewhat different memories signal events when one or more than one 18-1-0 trial occurs each day; and that retention interval deficits can arise owing to the same or similar memories' signaling different events. The results described limit the generality of three hypotheses suggested in two recent investigations: that as retention interval increases, rats find it increasingly difficult to remember and utilize serial position cues; that tracking in serial tasks is not influenced by number of trials each day; and that there are specific stimuli associated with each retention interval which, when changed, necessarily disrupt performance.