Three year outcomes in infants with a family history of autism and/or attention deficit hyperactivity disorder

Background

Most research on early outcomes in infants with a family history (FH) of autism has focussed on categorically defined autism, although some have language and developmental delays. Less is known about outcomes in infants with a FH of attention deficit hyperactivity disorder (ADHD).

Methods

Infants with and without a FH of autism and/or ADHD, due to a first-degree relative with either or both conditions, were recruited at 5 or 10 months. Three year outcomes were characterised using latent profile analysis (LPA) across measures of cognitive ability, adaptive functioning and autism, ADHD and anxiety traits (n = 131). We additionally ran an LPA using only autism and ADHD measures, and the broader LPA in an independent cohort (n = 139) and in both cohorts combined (n = 270).

Results

A Low Developmental Level + High Behavioural Concerns class had elevated autism, ADHD and anxiety scores, low cognitive and adaptive function, and included all but one child with autism. A Low Developmental Level + Typical Behaviour class had average cognitive ability and typical behaviour but low adaptive function. A Typical Developmental Level + Some Behavioural Concerns class had average cognitive and adaptive function but slightly elevated behaviour scores. A High Developmental Level + Typical Behaviour class had above average cognitive ability and typical behaviour. All four LPAs identified classes characterised by combinations of either, or both, Low Development Level and elevated behaviour scores, as well as a typically developing class. No classes had elevated autism or ADHD traits in isolation.

Conclusions

Some infants with a FH of autism or ADHD have atypical developmental and behavioural outcomes, but do not show strong autism or ADHD traits in isolation. The field needs to recalibrate aims and methods to embrace the broader transdiagnostic pattern of outcomes seen in these infants.

Learning by heart: cardiac cycle reveals an effective time window for learning

Cardiac cycle phase is known to modulate processing of simple sensory information. This effect of the heartbeat on brain function is likely exerted via baroreceptors, the neurons sensitive for changes in blood pressure. From baroreceptors, the signal is conveyed all the way to the forebrain and the medial prefrontal cortex. In the two experiments reported, we examined whether learning, as a more complex form of cognition, can be modulated by the cardiac cycle phase. Human participants ( experiment 1) and rabbits ( experiment 2) were trained in trace eyeblink conditioning while neural activity was recorded. The conditioned stimulus was presented contingently with either the systolic or diastolic phase of the cycle. The tone used as the conditioned stimulus evoked amplified responses in both humans (electroencephalogram from "vertex," Cz) and rabbits (hippocampal CA1 local field potential) when its onset was timed at systole. In humans, the cardiac cycle phase did not affect learning, but rabbits trained at diastole learned significantly better than those trained at a random phase of the cardiac cycle. In summary, our results suggest that neural processing of external stimuli and also learning can be affected by targeting stimuli on the basis of cardiac cycle phase. These findings might be useful in applications aimed at maximizing or minimizing the effects of external stimulation. NEW & NOTEWORTHY It has been shown that rapid changes in bodily states modulate neural processing of external stimulus in brain. In this study, we show that modulation of neural processing of external stimulus and learning about it depends on the phase of the cardiac cycle. This is a novel finding that can be applied to optimize associative learning.

Effect of iodinated contrast media on the phagocytic activity of human leukocytes. A new toxicity test

The effect of radiographic contrast media on zymosan-induced phagocytic activity of human blood samples was studied with an automatic luminometer. At iodine concentration of 0.2% biliary contrast media almost totally inhibited leukocyte phagocytosis. The effects of iohexol and iopamidol were nearly identical, eg, negligible inhibition at 0.05% and about 65% inhibition at 1%. Metrizamide, iodixanol, and iopentol cause no or little inhibition at concentrations 0.05% and 0.2% and about 50% inhibition at the concentration of 1% iodine. Among ionic contrast media, sodium salts inhibited leukocyte phagocytosis in vitro less than methylglucamine salts. Because the chemiluminometric method is rapid and easily reproducible even in large series, it may be useful in toxicity surveys of potential contrast media.