The response hierarchy of EEG and autonomic variables to tones of increasing intensity was studied during waking and sleep stages 2, REM, and SW (3 & 4 combined). Tones of 1000 Hz (5 sec duration, 55 sec ISI) were presented to 35 young adult male subjects. During waking, the tones began below awake auditory threshold and increased by 5 db until a motor response (button press) was made. During sleep, tones began at awake threshold and went to arousal threshold, i.e., motor response and/or an EEG change indicative of arousal. Changes in EEG, finger pulse amplitude, heart rate, skin potential, skin resistance, and respiration period were measured for each stimulus and were compared to a pseudostimulus response scored 25 sec prior to the actual stimulus. In the awake state, statistically significant responses (p < .05) were found for EEG, finger pulse, heart rate early deceleration, skin potential, and skin resistance to the tone at awake threshold, but not to tones at lesser db levels. During sleep, significant EEG responses were present to tones 30–25 db below arousal threshold, finger pulse 20–15 db below, and heart rate acceleration 20–5 db below. Significant skin potential, skin resistance, and motor responses were seen only at arousal threshold. Thus, in sleep, in contrast to waking, there were clear responses to stimuli below the arousal threshold, and there was definite ordering of the appearance of the various responses: EEG preceded the cardiovascular, with electrodermal and motor occurring only at arousal. This order was constant over sleep stages. Arousal thresholds were very similar across sleep stages in day sleepers (approximately 35 db above awake threshold). The threshold during stage 2 for night sleepers was about 15 db lower than that for day sleepers.

Autonomic response patterns of 20 male nonreaders, ranging in age from 7 years 11 months to 11 years 4 months, were compared with those of 20 matched controls. Analyses were made of the onset orienting response, the offset orienting response and anticipatory response as measured for heart rate, finger pulse and electrodermal pheonomena (skin potential and skin resistance). Nonreaders had lower mean skin conductance levels across trials, greater amplitude of skin resistance response to a novel stimulus (75 decibel tone), fewer electrodermal offset responses, fewer negative and diphasic skin potential responses, fewer electrodermal and heart rate anticipatory responses, slower motor reaction times, and a higher degree of sinus arrhythmia. All these differences between the groups were statistically significant. Habituation of the electrodermal, finger pulse, and heart rate onset responses did not differ, and no difference was found between groups as to the magnitude or shape of the heart rate onset response. Both groups showed decreasing skin conductance levels with increasing heart rate levels over trials. Data suggest nonreaders were physiologically less mature, unable to maintain a constant attentional level, and slower in "simple" learning than their matched controls. , 1967). In addition to problems in the language sphere, the maturational or developmental lag may also be reflected in deficits in neurophysiological, motor, and conceptual behavior. If the basis for dyslexia is biological, physiological measures such as the autonomic component of the orienting response might beused to discriminate between readers and nonreaders. Developmental dyslexia is thought by many to be a symptom of hereditary immaturity rather than of an actual lesion in the brain (Critchley, 1964; Money, 1966) and is viewed as a "dysfunction" rather than an incapacity (Johnson and MyklebustThe orienting response has been defined as an organism's initial response to the novel stimulus or to a change in stimulus. It is nonspecific as to stimulus and diminishes or disappears with repetition of the same stimulus *

No abstract

I t is well known that reticulmdothelial system (RES) depression through carbvn "blockade" temporarily increases the susceptilbility to svbsquen t hemorrhagic or traumatic shock (1-3) whereas RES stimulation, notably w i t h zymosan injection, increases resistance to the same stresses (2,4). These findings suggest that the physiological state ot the RES as measured by phagocytic capacity constitutes an important determinant of shock resistance. Glucan injection, on the other hand, also produces marked hyperphagocytosis but does not afford shock protection (4); it appears, therefore, that RES stimulation is not inevitably effective against shock. It seemed possible that another RES mechanism, perhaps immunological, might be operakive in the shock-protective effect of zymosan.Previous studies indicated that the RES plays an important role in antibody formation ( 5 ) and as a defense against infection (6). Thus, shock resistance induced by zymosan may involve the production of antibodies or other immune factors and the difference between zymosan and glucan in this regard may be on an immunological basis. Zymosan increases resistance to E . coli infections (7), enhances the bactericidal power of serum against gram-negative organisms (8), produces heat-stable antibodies ( 9 ) , dter5 properdin levels in vivo (10) and interacts with properdin in vitro (11). Furthermore, zymosan and glucan both enhance the primary and secondary immune responses to particulate antigens (12,13).If circulating endotoxin exerts a major dekterious effect during shock (14,15#), an immune mechanism for endotoxin inactivation codd also conceivably be a factor in shock protection. Freedman has repwted that tolerance to bacterial endotoxiin can be achieved by passive transfer of serum from enddoxintolerant donors to normal recipient animals ~- *This hvestkption was supported b y ResearchGrant HE 06588 from the National Heart Institute.(16). This approach has been used in the present study to evaluate the role of the immune response to zym0sa.n and g l u m injection in subsequent traumatic shock.Materials and Methods. Drum shock. Mde Sprague-DawIey albino rats weighing 2 5Cb300 gm were maintained on a standard diet with water ad libitum and were given a single iv injection of either 100 rn!g/kg z y m w (Standard Blrands, Stamford, Corm., Lot NO. 9B551) or g l u m (Standd Brands, Stamford, Conn., zld No. lF5500) or an equivalent volume of pyrogen-free saline. Seventytwo h o w later, the animals were turmbled in a modified Noble-Collip drum at 33 rpan for a total of 425 rev. using a technique previously described (4). The rats were closely observed and those living after 24 hours were considered survivors. Gross p t m o r t e m examinations were performed on 'dl fatalities; animals dying with the characteristic intestinal congestion and luminal hemorrhage but with no other apparent visceral organ damage were classified as shock mcmhlities; the data were analyzed with the chi-square test.Serum Preparation. Poolled serum was prepared from the b l d of...