The effects of piracetam upon visual event-related potentials in dyslexic children

Single-dose piracetam effects on global complexity measures of human spontaneous multichannel EEG

Global complexity of 47-channel resting electroencephalogram (EEG) of healthy young volunteers was studied after intake of a single dose of a nootropic drug (piracetam, Nootropil UCB Pharma) in 12 healthy volunteers. Four treatment levels were used: 2.4, 4.8, 9.6 g piracetam and placebo. Brain electric activity was assessed through Global Dimensional Complexity and Global Omega-Complexity as quantitative measures of the complexity of the trajectory of multichannel EEG in state space. After oral ingestion (1-1.5 h), both measures showed significant decreases from placebo to 2.4 g piracetam. In addition, Global Dimensional Complexity showed a significant return to placebo values at 9.6 g piracetam. The results indicate that a single dose of piracetam dose-dependently affects the spontaneous EEG in normal volunteers, showing effects at the lowest treatment level. The decreased EEG complexity is interpreted as increased cooperativity of brain functional processes.

Auditory evoked potentials in young patients with Down syndrome. Event-related potentials (P3) and histaminergic system

Subjects with Down syndrome exhibit various types of cognitive impairment. Besides abnormalities in a number of neurotransmitter systems (e.g. cholinergic), histaminergic deficits have recently been identified. Brainstem auditory evoked potentials (BAEPs) and auditory event-related potentials (ERPs), were recorded from 10 children (aged 11-20 years) with Down syndrome and from 10 age- and sex-matched healthy control subjects. In Down subjects, BAEPs revealed shortened latencies for peaks III and V with shortened interpeak latencies I-III and I-V. ERPs showed a delay of components N1, P2, N2 and P3. In addition, subjects with Down syndrome failed to show P3 amplitude reduction during repeated stimulation. To evaluate the cognitive effects of histaminergic dysfunction, ERPs were recorded from 12 healthy adults (aged 20-28 years) before and after antihistaminergic intervention (pheniramine) compared to placebo. Whereas components N1, P2, N2 remained unchanged after H1-receptor antagonism, P3 latency increased and P3 amplitude showed no habituation in response to repeated stimulation. The results suggest that the characteristic neurofunctional abnormalities present in children with Down syndrome must be the consequence of a combination of structural and neurochemical aberrations. The second finding was that antihistaminergic treatment affects information processing tested by ERPs similar to that seen with anticholinergic treatment.

Piracetam in developmental reading disorders: A review

This paper reviews the studies that have examined piracetam, the first of the nootropic drugs, as a treatment for developmental reading disorder. In various studies, 751 children have completed treatment in controlled double-blind trials using standardised tests of reading as outcome measures. Quantitative and qualitative review suggests that the findings are best interpreted as showing a statistical superiority of piracetam over placebo. Mechanism of action and clinical significance are discussed. The effect size is modest, but the drug is well tolerated and the balance of benefit over hazard is encouraging for future use.

Event related potentials recorded in normal and dyslexic subjects when reading in and out of context

Clinical evidence has shown that expectancy or anticipatory reactions influence the ability to read. It is possible that the reading problems shown by dyslexic children could be due to the absence of anticipatory hypotheses when they decode verbal material. Research was therefore carried out into these clinical observations to see if they could be detected on an electrophysiological level using a technique for recording Event Related Potentials (ERPs). In this study, our intention was to observe if there were any differences between a sample population of normal children and one of dyslexic children in the ERPs recorded on the presentation of words both in and out of context. The words recorded during the reading in context were: the word "la" (the feminine article "the" in Spanish), an "intermediate" word and a "final" word in a series of sentences. The first two have a greater anticipatory load than the reading of the final word since this is the word that closes the meaning of the sentence. Furthermore, as a control, the ERPs that were produced when reading isolated words were recorded, a situation that does not require the presence of anticipatory processes. The control group was made up of subjects with adequate school performance and no pathological background, and the experimental group was composed of subjects whose performance on a psychoeducational battery, previously administered to 120 Mexican children, had been found to be two standard deviations below the established norms. Following the 10-20 international system, electrodes were placed in zones F3, Cz, P3, O1 and O2 and referred to both earlobes. Statistical analysis revealed significant differences between groups in the amplitude of the ERP recording in the left occipital zone for all conditions when reading in sentences ("la," "intermediate" and "final"). It is suggested that this cortical zone participates in decoding verbal material and that it is deficient in subjects with reading problems.

The acute and chronic administrations of piracetam affect the movement-related brain macropotentials

Neurophysiological and neurochemical studies have demonstrated that piracetam improves learning and memory both in animals and humans. In recent years it has been shown that when a subject is engaged in a motor perceptual task, some psychomotor functions are correlated with a consistent pattern of brain electrical activity. Given the relationship between the movement-related brain macropotentials (MRBMs) and the cognitive processes associated with them, we considered the MRBMs particularly suitable for the neurophysiological assessment of the efficacy of piracetam in man. The aim of this study was to test the acute and chronic effect of piracetam administration on the MRBMs in normal children during the performance of a motor perceptual task. The design was a triple-blind study, during which the subjects took either placebo or piracetam in random sequence, with a washout period of 3 weeks. The dose was 170 mg/kg for the acute treatment and 140 mg/kg/day for chronic treatment. No side-effects were reported by the children during or after acute or chronic treatment with piracetam. There was no statistically significant difference between placebo or piracetam treatment with regard to 'performance', which was already optimal at baseline, and to electromyographic activity. On the contrary, the MRBMs were significantly modified by treatment. In particular the Bereitschaftspotential was present as a positive shift during acute treatment with piracetam and increased after chronic treatment. Skilled performance positivity (SPP) amplitudes were significantly increased and SPP latency reduced by chronic treatment with piracetam. piracetam appears to act on the catecholaminergic and cholinergic systems via an increase of the inhibitory hyperpolarizing processes.

A brief review of studies of piracetam in dyslexia

Several double-blind studies of the effects of piracetam in developmental dyslexia are reviewed. There is general agreement among studies that piracetam appears to improve reading performance.