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Major depressive disorder (MDD) is characterized by dramatic and persistent worsening of mood, as well as a subjective feeling of time slowing. However, experimental data on time perception are inconsistent. As serotonergic dysfunction implicated in MDD etiology, we aim to examine time perception in MDD through the framework of lossy temporal integration model, previously also related to serotonergic transmission. Thirty-one patients with recurrent depressive disorder in partial remission and thirty control participants, without a history of psychiatric and neurological disorders, performed duration discrimination of visual stimuli (duration ranges from 3.2 to 6.4 s) and subjective minute production tasks. To infer about central serotonergic transmission, an electroencephalogram in response to the 1000 Hz tone of different intensity (50, 60, 70 and 80 dB SPL) was recorded. Patients with MDD shorten the past durations in the duration discrimination task significantly less than controls, thus being more objective. No difference in the subjective minute production was recorded. Patients with MDD have also exhibited larger auditory evoked potentials in response to the tones of high intensity (70 and 80 dB SPL) when compared with the controls. This resulted in a steeper slope of auditory evoked potentials by intensity function. These converging findings suggest a lower loss rate of neuronal temporal accumulator modulated by serotonergic transmission in patients with MDD. • Patients with depression shrink duration less than normotypical individuals. • The intensity modulation of auditory evoked potentials is higher in depression. • Auditory evoked potential on high intensity stimuli is larger in depression. • Lower serotonin transmission in depression can be inferred. • Lower loss rate of temporal accumulator in depression accounts for the results. [ABSTRACT FROM AUTHOR]

Paralinguistic features, such as prosody (tempo, loudness, and timbre), are an essential marker of a speaker's emotional state. Abnormal processing of emotional prosody may result in the deficient social behavior associated with autism spectrum disorder (ASD). Two groups of children participated in our study: the ASD group consisted of 30 preschoolers from 4 to 6 years of age and 24 typically developing (TD) peers. An electroencephalogram (EEG) was acquired in response to a combination of syllables uttered with the following types of emotional prosody: joy, anger, sadness, fear, and calmness. Children with ASD and TD showed a similar EEG oscillatory response to fear and anger prosodies. Significant group differences in power spectral density (PSD) were detected for sad and joy intonations. The PSD differences between pairs of intonations, such as joyful and sad, sad and neutral, or joyful and neutral, were significantly higher in the control group than in the ASD group. EEG responses to affective prosody also demonstrated less hemispheric asymmetry in the ASD than in the TD group. Our results suggest that difficulties in emotional prosody recognition in autistic children could be based on the atypical processing of specific acoustic features coding differences between sad, neutral, and joyful intonations and could underlie emotional perception deficits in individuals with ASD. • Results suggest autistic children have difficulty distinguishing speech intonations of sad and joy. • Children with ASD and TD children showed a similar EEG oscillatory response to fear and anger prosody. • EEG response to affective prosody demonstrated less hemispheric asymmetry in the ASD group. [ABSTRACT FROM AUTHOR]

• Fostered children's cortisol levels were no better compared to orphanage children. • Children of target groups showed both altered lower and higher levels of cortisol. • Child-to-child or adult-to-child affective touch protocol was performed in both groups. • An affective touch protocol leads to the balancing of cortisol level in both groups. • Resistance to stress is associated with balancing cortisol levels. Institutionalized children are often deprived of affective touch. Such tactile deprivation often leads to constant stress, as measured by the levels of salivary cortisol. We report here the impact of an affective touch program, optimized to activate a specific population of unmyelinated mechanosensitive nerves in the skin called c-tactile afferents (CT) on stress resistance. Two populations of children (age 4–10) were recruited: (i) a cohort living in an orphanage and (ii) a fostered cohort. Both groups received the affective touch program daily for 10–15 min for 5–6 weeks. A cohort of age-matched children living in a family environment acted as a control group and did not receive any instructions for tactile stimulation. Salivary cortisol was collected at the beginning (T1) and at the end (T2) of the study in all three groups. For institutionalized and fostered children there was a significant improvement in the level of cortisol (p < 0.0001) between T1 and T2, which is manifested in the balancing cortisol levels: a decrease where it was elevated and an increase, where the critically low level testified to the distress of the child. Balancing cortisol levels is a process of recovery to normal values, which indicates the restoration of neurohumoral mechanisms of stress regulation. The effect of balancing cortisol levels was more pronounced in the group of fostered children compared to the group of orphanage children (p = 0.0326). The children in the control group had no significant differences. [ABSTRACT FROM AUTHOR]