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L Leinonen

Publications and source records attributed to L Leinonen.

At least 19 recordsLinked to original sources
PubMed2001

Neurological impairments and sleep-wake behaviour among the mentally retarded.

The objective of the present study was to evaluate the relationship between the sleep-wake behaviour and neurological impairments among mentally retarded people. The sleep-wake behaviour of 293 mentally retarded subjects living in a rehabilitation center was studied by a standardized observation protocol carried out by trained staff members. The protocol consisted of brief check-ups of the subjects' sleep-wake status at 20-min intervals for five randomly chosen 24-h periods during 4 months. From the raw data five sleep-wake behaviour variables were formed. The data concerning the subject characteristics (age, body mass index (BMI), gender, degree of mental retardation, presence of locomotor disability, that of epilepsy, blindness or deafness and the usage of psychotropic medications) were collected from the medical records. Two main findings emerged: (1) severe locomotor disability, blindness and active epilepsy were found to be independent predictors of increased daytime sleep and increased number of wake-sleep transitions and (2) the subjects with a combination of two or all three of these impairments had a significantly more fragmented and abnormally distributed sleep than those with none or milder forms of these impairments. Age, BMI, degree of mental retardation and the studied medications played a minor role in the sleep disturbances of the study population. Finally, deafness was not found to be associated with any of the measured sleep-wake variables.

Adolescent↗
PubMed1999

Multiple endocrine neoplastic-associated thymic carcinoid tumour in close relatives: octreotide scan as a new diagnostic and follow-up modality. Two case reports.

Thymic carcinoid tumours constitute less than 1% of all carcinoids, and differ markedly from true thymomas in natural history, morphology, prognosis and therapeutic options. New clinical and diagnostic modalities are described in two brothers with thymic carcinoid associated with multiple endocrine neoplasia syndrome. Octreotide scintigraphy proved useful for diagnosis and follow-up, and somatostatin receptor positivity may provide new prospects for treatment of non-resectable or recurrent tumour.

Carcinoid Tumor↗
PubMed1997

Voice reactions to histamine inhalation in asthma.

Susceptibility to voice reactions during a histamine provocation test was studied in 21 asthmatics and 21 healthy subjects. Speech samples were recorded before, and 5 and 15 min after histamine inhalation, and the samples were rated by six speech pathologists. Deterioration of voice quality occurred in 2/12 asthmatic men and in 3/9 asthmatic women within 5 min after histamine inhalation; no change was observed between 5 and 15 min. Voice reactions were not related to the degree of bronchial obstruction: the subjects with the most pronounced decrease in peak expiratory flow (PEF) (60-61% in three subjects) did not develop voice reactions, and PEF did not decrease in one subject with voice reactions. No voice reactions were observed in the healthy subjects.

Administration, Inhalation↗
PubMed1997

Expression or emotional-motivational connotations with a one-word utterance.

The expression of "naming," "commanding," "angry," "frightened," "pleading," "astonished," "satisfied," "admiring," "scornful," and "sad" was with the word [saara] spoken by 12 subjects. Using the same connotations, the 120 utterances were categorized by 73 listeners. Most samples were agreed on by 50%-99% of the judges. Most samples of "astonished," "angry," "frightened," and "commanding" were judged as intended, while "pleading" was often confused with "sad," and "content" with "admiring." Acoustic differences between the categories were examined for F0, duration, and sound pressure; spectral features of [aa] were visualized with the self-organizing map of Kohonen. Most intraspeaker variation of mean F0, FO range, sound pressure, and duration took place during the [aa] segment. Peak sound pressure, mean FO, and spectral energy distribution of [aa] differentiated among "commanding," "angry," "frightened," "naming," and "sad.". Specific intonations of the [aa] segment were encountered for "astonished," "scornful," and "pleading.". The best-conveyed "admiring" samples were distinguished from "content" by spectral cues for a breathy voice quality.

Adult↗
PubMed1997

Categorization of voice disorders with six perceptual dimensions.

To obtain a perceptual reference for acoustic feature selection, 94 male and 124 female voices were categorized using the ratings of 6 clinicians on visual analog scales for pathology, roughness, breathiness, strain, asthenia, and pitch. Partial correlations showed that breathiness and roughness were the main determinants of pathology. The six-dimensional ratings (the six median scores for each voice) were categorized with the aid of the Sammon map and the self-organizing map. The five categories created differed with respect to the breathiness/roughness ratio and the degree of pathology.

Adult↗
PubMed1996

Cul-de-sac hypernasality test with pattern recognition of LPC indices.

Acoustic differences between samples of [i], [u], and [a] uttered in nose-open and nose-obstructed condition were studied in 6 women with isolated cleft palate and pathological nasalance scores and 9 healthy women with normal nasalance scores. The speech samples were depicted by 14-component vocal tract area feature vectors obtained by linear prediction and the differences between the samples were studied with a self-organized feature map. Each location on the map corresponds to a certain signal pattern, neighboring locations to similar patterns. The group of healthy subjects differed from the patients for vowels [i] and [u] but not for [a]. In the patients the nose obstruction induced a significant change in the location of these vowel samples on the map. In healthy subjects no such changes were detected. The results agreed with perceived differences between the subjects.

Adolescent↗
PubMed1995

Locomotor activity and melatonin rhythms in rats under non-24-h lighting cycles.

The adjustment of pineal melatonin and locomotor activity rhythms to 10:10-h light:dark (LD) or 14:14-h LD cycles was studied in male Wistar rats. Both lighting conditions were thought to be outside the limits of entrainment of the rest-activity rhythm in this species. We assumed that the rhythm of pineal melatonin synthesis might be more adaptable. As expected, the locomotor activity rhythm was not adjusted to the 10:10-h LD cycles. Under these conditions, a free-running component (25 h) became dominant. Under the 14:14-h LD cycles, however, an unexpected adaptation occurred within 10 days. The profiles of the pineal melatonin contents measured on days 5 and 30 under the 10:10-h LD and on day 7 under the 14:14-h LD schedule were in line with the estimated free-running oscillations, but the profile on day 21 under the 14:14-h LD schedule was not. This melatonin pattern fitted the LD-adjusted activity rhythm. Thus, the melatonin rhythm did not adapt better than the activity rhythm to the exotic LD cycles. Instead, parallel changes were found.

Animals↗
PubMed1994

Spectral pattern recognition of improved voice quality.

The self-organizing map (a neural network) was applied to the spectral pattern recognition of voice quality in 34 subjects: 15 patients operated on because of insufficient glottal closure and 19 subjects not treated for voice disorders. The voice samples, segments of sustained /a/, were perceptually rated by six experts. A self-organized acoustic feature map was first computed from tokens of /a/ and then used for the analysis of the samples. The locations of the samples on the map were determined and the distances from a normal reference were compared with the perceptual ratings. The map locations corresponded to the degree of audible disorder: the samples judged as normal were overlapping or close to the normal reference, whereas the samples judged as dysphonic were located further away from it. The comparison of pre- and postoperative samples of the patients showed that the perceived improvement of voice quality was also detected by the map.

Adult↗
PubMed1993

Melatonin, cortisol and body temperature rhythms in Lennox-Gastaut patients with or without circadian rhythm sleep disorders.

The daily rhythms of melatonin, cortisol and body temperature were studied in 16 institutionalized subjects with the Lennox-Gastaut syndrome. The results of 9 subjects with normal daily rhythms of sleep and wakefulness (group 1) were compared with those of 7 subjects with disordered sleep (group 2). Salivary samples were collected and axillary temperature was measured every 2 h during two or three separate 26-h periods. The hormones were measured by radioimmunoassays. The rhythms were characterized with single cosinor analysis. Two subjects in group 1 and six subjects in group 2 had abnormalities in their rhythms of temperature, cortisol or melatonin. All three rhythms were disrupted in two subjects of group 2. These two subjects were the only ones with disrupted cortisol rhythm. The diversity of rhythm pathologies suggested partly separate regulatory mechanisms for each rhythm. The co-occurrence of circadian rhythm sleep disorders with the deteriorated melatonin rhythm raised the question as to whether the sleep disorders of these subjects, like those of subjects with healthy brains, could be relieved by the induction of normal melatonin rhythm.

Adolescent↗
PubMed1993

Self-organized acoustic feature map in detection of fricative-vowel coarticulation.

The self-organizing map, a neural network algorithm of Kohonen, was used for the detection of coarticulatory variation of fricative [s] preceding vowels [a:], [i:], and [u:]. The results were compared with the psychoacoustic classification of the same samples to find out whether the map had extracted perceptually meaningful features of [s]. The map distinguished samples of [s] in front of [u:] from those in front of [a:] or [i:] throughout the fricative duration. Samples of [s] preceding [a:] and [i:] were distinguished from each other only just before (about 40 ms) the vowel onset. The results agreed with the perceptual classifications. Most judgments (82%) of [s] in front of [u:] were correct, and this variant of [s] was recognized from the first and second halves of segmented fricatives equally well. Samples of [s] in front of [a:] and [i:] were distinguished from each other less accurately. When halves of segmented [s] were perceptually judged, the differentiation between the following [a] and [i] was possible only on the basis of the second half of the fricative. The results demonstrate that the self-organizing map is a useful tool for the extraction of intersubject regularities in speech spectra. The map also provides an easily understandable, on-line, visualization of speech that can be used as feedback in therapy and education.

Acoustic Stimulation↗
PubMed1993

Hormonal and locomotor activity rhythms in rats under 90-min dark-pulse conditions.

The ability of a short dark pulse to entrain the circadian rhythms in rats was investigated. Pineal melatonin contents and serum levels of corticosterone and thyrotropin, a thyroid-stimulating hormone (TSH), were measured and locomotor activity was recorded under 12:12-h light-dark cycles (LD; darkness from 1800 to 0600 h) and under a 22.5:1.5 h LD lighting schedule (darkness from 1800 to 1930 h). The 90-min dark pulse was enough to trigger the rise of melatonin synthesis, but a free-running component was detected in the locomotor activity. Corticosterone levels showed diurnal variations under both conditions. The decrease of corticosterone and the increase of melatonin were phase locked, but the corticosterone pattern was distorted under the dark-pulse conditions. The 24-h rhythm of TSH was detectable in the control but not in the dark-pulse schedule. The results suggest that the circadian rhythm of pineal melatonin and the decrease of serum corticosterone levels were entrainable by the dark pulses, whereas the increase of corticosterone, the variations of TSH, and the rhythm of locomotor activity were not.

Animals↗
PubMed1993

Acoustic pattern recognition of fricative-vowel coarticulation by the self-organizing map.

Word-initial samples of fricative [s] preceding vowels [a:], [ae:], [e:], [i:], [u:], [o:], and [y:] in Finnish words were studied with the self-organizing map. An acoustic map was first calculated from speech samples of women without speech disorders, and then the [s] samples were measured on this map. In all 10 subjects the [s] samples preceding the rounded vowels [u:] and [o:] clearly differed from the samples in front of unrounded [a:], [ae:], [e:], and [i:]. The coarticulatory phenomena observed on the map were due to changes in the composition and stability of the fricative spectrum.

Adult↗
PubMed1993

Acoustic pattern recognition of /s/ misarticulation by the self-organizing map.

The [s] samples of 11 women, psychoacoustically classified as acceptable/unacceptable, were studied with the self-organizing map, the neural network algorithm of Kohonen. The measurement map had been previously computed with nondisordered speech samples. Fifteen-component spectral vectors, analyzed with the map, were calculated from short-time FFT spectra at 10-ms intervals. The degree of audible acceptability correlated with the location of the sample on the map. Spectral model vectors in different map locations depicted distinguishing spectral features in the [s] samples analyzed. The results demonstrate that self-organized maps are suitable for the extraction and measurement of acoustic features underlying psychoacoustic classifications, and for on-line visual imaging of speech.

Adolescent↗
PubMed1992

Pineal melatonin and locomotor activity of rats under gradual illuminance transitions.

The locomotor activity and pineal melatonin patterns of adult male rats were compared under two different lighting regimes. The animals were kept 8 days under 12/12 h light/dark cycles with abrupt or slowly decreasing and increasing transitions (twilight periods about 2 h). The onsets of high activity and melatonin rise were phase-locked in the two conditions and related to about half-maximal illuminance level of the gradual dusk. The high activity of the control rats stopped 30-60 min before the abrupt light onset and the rats under the gradual lighting transitions ceased the locomotor activity at about 1 hour before the half-maximal illuminance. The melatonin peak levels were found 4 h before the abrupt lights-on time. Under the slow illuminance transitions the average melatonin peak was related to the illuminance level between maximum and minimum in the morning. Thus, both the melatonin rhythm and the rest-activity rhythm under the gradual dawn and dusk were adjusted according to about half-maximal illuminances in the present conditions.

Animals↗
PubMed1992

Dysphonia detected by pattern recognition of spectral composition.

The vowel [a:] in a test word, judged normal or dysphonic, was examined with the Self-Organizing Map; the artificial neural network algorithm of Kohonen. The algorithm produces two-dimensional representations (maps) of speech. Input to the acoustic maps consisted of 15-component spectral vectors calculated at 9.83-msec intervals from short-time power spectra. The male and female maps were first calculated from the speech of healthy subjects and then the [a:] samples (15 successive spectral vectors) were examined on the maps. The dysphonic voices deviated from the norm both in the composition of the short-time power spectra (characterized by the dislocation of the trajectory pattern on the map) and in the stability of the spectrum during the performance (characterized by the pattern of the trajectory on the map). Rough voices were distinguished from breathy ones by their patterns on the map. With the limited speech material, an index for the degree of pathology could not be determined. A self-organized acoustic map provides an on-line visual representation of voice and speech in an easily understandable form. The method is thus suitable not only for diagnostic but also for educational and therapeutic purposes.

Adolescent↗
PubMed1991

Continuous recording of locomotor activity in groups of rats: postweaning maturation.

A method was developed for continuous recording of locomotor activity in ten groups of rats housed in standard plastic cages under controlled lighting conditions. An inexpensive pressure transducer detected movements in the cage, and a light resistor monitored the lighting. The output voltages from the sensors were digitized, integrated for 5 s, and stored for off-line analysis. The data from separate cages were averaged for the detection of statistical differences between the experimental groups. The method was applied to study maturational changes after weaning. Wistar rats were recorded from 21 to 62 days of age under 12/12 h light/dark cycle. The cumulative activity distributions of the pups of 4 and 5 weeks of age differed significantly from those of 7-9 weeks, or older. Differences between the rats aged 8 or 9 weeks and the older adults were less consistent, but still detectable. The cumulative activity distributions of the males and females did not differ significantly from each other.

Aging↗