Andrew T. Russell

The Phenomenology of Schizophrenia Occurring in Childhood

Thirty-five children, aged 4 to 13 (X = 9.54), meeting strict DSM-III criteria for schizophrenia, are described. The subjects were diagnosed using a new semistructured interview. All were in the normal range of intelligence (mean IQ = 94) and free of neurological disorders. Characteristic auditory hallucinations were present in 80% and delusions in 63% of the sample. The mean age of onset of psychotic symptoms was 6.9 years. Premorbid histories of attention deficit, conduct disturbance and/or developmental abnormalities were common. The nature and content of psychotic symptoms varied with developmental stage. The phenomenological presentation of the sample was similar to previous studies of young schizophrenic children.

Prepulse inhibition of startle and the neurobiology of primary nocturnal enuresis

BACKGROUND Children with primary nocturnal enuresis (PNE) wet the bed during all stages of sleep and irrespective of state of arousal, suggesting that during sleep, when voluntary, i.e., cortical control, is not available, the signal from the distended bladder is not registered in the subcortical centers inhibiting micturition. Deficient prepulse inhibition (PPI) of startle has been reported in PNE. This study evaluates the association of this PPI deficit in PNE with comorbidity with attention-deficit hyperactivity disorder (ADHD) and with intelligence. METHODS Prepulse modulation of startle was studied in 96 boys with PNE and 105 nonenuretic boys using intervals of 60, 120, and 4000 msec between the onset of a 75-dB 1000-Hz tone and a 104-dB noise burst. Thirty-one percent of the enuretic and 36% of the nonenuretic boys were diagnosed with ADHD. RESULTS After adjustment for presence or absence of ADHD, lower or higher IQ, age, and unmodulated startle amplitude, there was a significant association between PNE and deficient PPI of startle following the 120-msec prepulse interval. Those enuretic boys who also were ADHD or had higher performance IQs (> or = 110) showed the greatest PPI deficit. CONCLUSIONS A common deficiency of inhibitory signal processing in the brain stem may underlie both deficient PPI and the inability to inhibit micturition in PNE. Strong familiarity for PNE, ADHD, and intelligence suggests a possible genetic mediation of these effects.

Transmission of primary nocturnal enuresis and attention deficit hyperactivity disorder.

Primary nocturnal enuresis (PNE) is a prevalent disorder among children with a complex mode of inheritance. Family, twin, and linkage studies have provided evidence that genetic factors underlie the familiarity of PNE. Linkage investigations support the hypothesis that PNE is heterogeneous, and the genetic heterogeneity may be reflected in co‐morbid clinical conditions such as attention deficit hyperactivity disorder (ADHD). This study used a family study method and examined the transmission of PNE in relatives of PNE and control probands with and without ADHD, to determine if these disorders co‐occur due to common genetic susceptibilities or other, i.e. non‐genetic, reasons. This study concluded that the pattern of inheritance found is consistent with the independent transmission of PNE and ADHD.

Affective Valence and Arousal in ADHD and Normal Boys During a Startle Habituation Experiment

OBJECTIVE To measure two dimensions of emotion (affective valence and arousal) in 29 boys with attention-deficit hyper-activity disorder (ADHD) and 32 normal boys. METHOD After a startle habituation experiment during which these subjects heard 40 startling sounds while watching a silent interesting movie, they were asked 12 questions (categorized a priori into questions relating to affective valence and to arousal) about their emotional reactions to these putatively unpleasant and pleasurable stimuli. Responses were recorded for the two dimensions of emotion, using two cartoon strips in each of which five expressions of a cartoon character varied linearly from happy to unhappy (affective valence dimension) and calm to excited (arousal dimension). RESULTS Factor analyses of the 12 responses revealed four factors in which the highest loadings were for affective valence to the startle responses, affective valence to the silent movie, arousal, and scary feelings. Relative to the normal group, the responses of the ADHD group were significantly biased toward pleasurable valence to the startling stimuli and to the silent movie, with a trend toward hypoarousal. Startle magnitude and habituation were similar in both groups. The normal tonic heart rate acceleration throughout the experimental session was not sustained in the ADHD group. CONCLUSIONS The self-reports of affective valence biased in the direction of pleasure and away from displeasure and the trend toward hypoarousal suggest an emotional dysfunction in ADHD.

HABITUATION OF P300 AND REFLEX MOTOR (STARTLE BLINK) RESPONSES TO REPETITIVE STARTLING STIMULI IN CHILDREN

Positive EEG deflections with the latency and scalp distribution of the P300 accompany startle in response to loud auditory stimuli in a non-task context. The purpose of this investigation is to determine if habituation would have effects on the P300 similar to those on the startle blink. Thirty-four normal 7 to 11-year-old boys from a startle habituation study had EEG recordings of sufficient quality to provide data for the current study. Startle was measured both as orbicularis oculi EMG and vertical EOG and P300 was recorded at Pz in response to 40,104 dB bursts of white noise presented at 23-s intervals. Both the startle response and the P300 habituated toward asymptotic levels after the first 28 trials, suggesting that both startle and the subsequent cognitive evaluation of the startling stimulus, reflected in the P300 response, are modulated by a common neurophysiological mechanism extrinsic to the direct startle pathway. A modest significant correlation between the P300 and the vertical EOG peak latencies for the initial trials suggests that the cognitive evaluation of the startling stimulus may also include evaluation of the reflex response to that stimulus. Analyses of the within-subject associations between startle and P300 initial amplitudes and rates of habituation showed that these parameters varied independently within the individual subject, suggesting that the P300 is not a component of the startle response. Rather, it reflects an evaluation of the startling stimulus, decreasing in amplitude as the surprising value of the startling stimulus decreases with habituation.

Moral judgment in relation to behavioral and cognitive disorders in adolescents

The capacity for formulating moral judgments shown by 20 emotionally disturbed, cognitively delayed adolescents was related to their social behaviors as observed in a classroom situation. Adolescents reported by their teachers to be shy and submissive were less capable of reasoning about moral issues than were adolescents who were seen as more assertive and socially engaged. The level of moral judgment was not a function of intelligence or ability to understand concrete operations. The implication that social engagement is a critical determinant of moral judgment for these adolescents is discussed.

SERVING CHILDREN WITH EMOTIONAL OR BEHAVIOR DISORDERS: Implications for Educational Policy

Four major issues in the education of children with emotional or behavioral disorders--problems in diagnostic eligibility for special education services; economic demands which dictate restoring the primacy of the teacher; barriers to interdisciplinary cooperation with parents and teachers; and controversial treatments for school children--are discussed, and the need for effective interdisciplinary cooperation is emphasized.

Prepulse inhibition of startle, intelligence and familial primary nocturnal enuresis

Previous studies have shown a significant reduction of prepulse inhibition of startle in boys with primary nocturnal enuresis. Those enuretic boys who had higher IQs showed less prepulse inhibition. This study evaluates the association of prepulse inhibition and IQ in primary nocturnal enuresis in respect to family history of primary nocturnal enuresis. Prepulse inhibition of startle was studied in 83 boys with primary nocturnal enuresis and 57 non‐enuretic boys using an interval of 120 ms between the onset of a 75 dB 1000 Hz tone and a 104 dB noise burst. Of the boys with primary nocturnal enuresis, 56 had a family history of primary nocturnal enuresis and 27 had no family history (no first‐degree relative). Of the 57 non‐enuretic boys, 42 also had no family history (no first‐degree relative) of primary nocturnal enuresis, while 15 did have a positive family history. Associations between prepulse inhibition and IQ scores were compared among these four groups. Strong and significant associations between prepulse inhibition deficit and higher IQ scores in the enuretic group with familial primary nocturnal enuresis were unique in comparison to the other groups.

Modulation of startle and the startle-elicited P300 by the conditions of the cued continuous performance task in school-age boys

OBJECTIVES This study compares the modulation of the startle response by conditions requiring response preparation, production, and inhibition during a cued continuous performance task (CPT) in children to the results of previous studies in adults and evaluates the modulation of the startle-elicited P300 under the same conditions. The latter variable, reflecting the cognitive processing of the startling stimulus (SS), has not been studied under these conditions. METHODS Normal boys completed a cued CPT in which the cue was the letter T, the go condition requiring a button press was an X following the T, and the no-go condition requiring response inhibition was a letter other than X following the T. SS were presented 450 ms following the letter of interest in each condition. The amplitudes of the startle-elicited P300 at Fz, Cz, and Pz and the startle blink were compared in the different CPT conditions. RESULTS The startle blink, measured by orbicularis oculi electromyography, was not inhibited by the no-go CPT condition as is the case in adults. The vertical electro-oculogram was actually largest in the no-go condition. The startle-elicited P300 showed a central predominance and was significantly larger in the no-go condition and in the cue condition than in the go condition. CONCLUSIONS The absence of inhibition of the startle response during the no-go condition probably reflects a relative inefficiency of prefrontal cortical mechanisms that mediate response inhibition in children compared to adults. The enhanced startle-elicited P300 in the no-go and cue conditions of the CPT reflects cognitive processing of the SS that has been influenced by response inhibition or its anticipation.