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The relationship between neuronal activity within the nucleus basalis (NB) and conditioned neocortical EEG activation was investigated in New Zealand rabbits during Pavlovian differential conditioning. Twenty- seven of 56 neurons recorded in conditioned animals demonstrated a significantly greater change in activity to a tone (CS+) that predicted the occurrence of a mildly aversive unconditioned stimulus when compared to a tone (CS-) that did not. Twenty-four of these 27 neurons demonstrated a significant increase in activity to the CS+ compared to the CS-, while the remaining three neurons demonstrated a significant decrease in activity to the CS+ compared to the CS-. In 24 of these 27 neurons (89%) these changes in neuronal activity during CS presentations correlated significantly with a decrease in the power of delta activity in the EEG. In addition, 13 of these 24 neurons (54%) demonstrated significant correlations between neuronal activity and the power of delta activity during CS-free periods. In experimentally naive animals, the activity of 10 of 22 neurons (45%) recorded within the region of the NB correlated with the power of delta activity in the EEG during stimulus-free periods. These results complement a growing body of evidence and provide strong support for the hypothesis that the NB contributes to neocortical activation in the conscious animal.

SUMMARY1. In both anaesthetized and decerebrate cats the cerebellar cortex (lobules VI, VII, VIII, IX and X) and the fastigial nucleus (f.n.) have been stimulated electrically, and chemically, while recording changes in phrenic nerve discharge, heart rate, arterial blood pressure and renal and femoral blood flow.2. Stimulation of lobules VI, VII, VIII and Xb failed to elicit any cardiovascular or respiratory changes. Activation of lobule IX (the uvula), and in some preparations sub-lobule Xa, evoked cardiovascular and respiratory responses consistently. In the anaesthetized cat, electrical stimulation of the uvula evoked apnoea, a small bradycardia and a depressor response associated with vasodilatation in the hindlimb vascular bed. In contrast, stimulation in an equivalent region in a decerebrate preparation elicited an apneustic discharge, a pronounced tachycardia and a rise in arterial pressure with vasoconstriction in both renal and femoral vascular beds. In both the anaesthetized and decerebrate animals the pattern of response elicited by chemical activation was identical to that seen with electrical stimulation.3. Electrical, or chemical, stimulation after administration of anaesthetic to the decerebrate cat then evoked an identical pattern of response to that seen in the 'intact' anaesthetized animal. This evidence suggests that the reversal in the pattern of the response is an effect of the anaesthetic agent and not the decerebration itself.4. The only area of the f.n. to produce cardiovascular effects was the rostral region.

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The present study measured the comprehension‐based silent reading efficiency of U.S. students in grades 2, 4, 6, 8, 10, and 12. Students read standardized grade‐level passages while an eye movement recording system was used to measure reading rate, fixations (eye stops) per word, fixation durations, and regressions (right‐to‐left eye movements) per word. Eye movement recordings were regarded as valid only if students demonstrated a comprehension level of at least 70% after reading a passage and answering a series of true/false questions. Reading rates increased over grades, with two exceptions: (a) between grades 6 and 8, growth in reading rate appeared to plateau; and (b) between grades 10 and 12, reading rate increases were seen only among students in the upper two quartiles. Changes in the other three efficiency measures reflected similar patterns of reading efficiency development over grades. The reading efficiency of students in this study was also compared with that of a sample of students from 1960, using norms reported by Taylor (1965) and validated by Carver (1989). Comprehension‐based silent reading rates in grade 2 were comparable across the 50‐year span, but the cross‐grade growth trajectory was much shallower in the present study than it was in 1960. These results suggest that present‐day students may not achieve the same level of word‐reading automaticity as did their 1960 counterparts.