Septal driving of hippocampal theta rhythm as a function of frequency in the free-moving male rat

Abstract In free-moving male rats chronically implanted with electrodes in the septal area and hippocampal formation it was possible to drive the hippocampal theta rhythm by low-frequency septal stimulation. Measurements of the function relating the threshold driving current to stimulation frequency demonstrated a minimum at an inter-pulse interval of 130 ms (7.7 Hz) over the range 100–170 ms. The observed function was reliably obtained in single animals, showed good inter-observer agreement and good stability over time. and was little affected by the exact stimulation site (medial or lateral septum), recording site (dorsomedial subiculum or hippocampus) or stimulation parameters (pulses or interrupted high-frequency trains) When thresholds for septal elicitation of evoked potentials were similarly estimated there was no minimum at 7.7 Hz. There was also no deviation from linearity at 7.7 Hz when the frequency of the hippocampal theta rhythm was plotted as a function of the intensity of reticular stimulation. Movement accompanied theta rhythm elicited from the reticular formation. but not theta rhythm elicited by septal stimulation.

[1]  J. Gray,et al.  Effects of septal driving of the hippocampal theta rhythm on resistance to extinction. , 1972, Physiology & behavior.

[2]  H. Klüver,et al.  On the Use of Azaporphin Derivatives (Phthalocyanines) in Staining Nervous Tissue , 1954 .

[3]  W. Ganong,et al.  Relation of brain 5-hydroxytryptamine content to the diurnal variation in plasma corticosterone in the rat. , 1971, Neuroendocrinology.

[4]  T. Lømo,et al.  MODE OF CONTROL OF HIPPOCAMPAL PYRAMIDAL CELL DISCHARGES , 1970 .

[5]  D. Hubel.  Tungsten Microelectrode for Recording from Single Units. , 1957, Science.

[6]  P. Donovick.  Effects of localized septal lesions on hippocampal EEG activity and behavior in rats. , 1968, Journal of comparative and physiological psychology.

[7]  C. H. Vanderwolf,et al.  Hippocampal EEG and behavior: changes in amplitude and frequency of RSA (theta rhythm) associated with spontaneous and learned movement patterns in rats and cats. , 1973, Behavioral biology.

[8]  P. Kelly,et al.  Effect of minor tranquillisers on hippocampal θ rhythm mimicked by depletion of forebrain noradrenaline , 1975, Nature.

[9]  D. H. Vandercar,et al.  Lightweight FET circuit for differential or single-ended recording in free-moving animals. , 1972, Physiology & behavior.

[10]  J. Gray,et al.  Septal self-stimulation and hippocampal activity. , 1971, Physiology & behavior.

[11]  G. W. Snedecor.  Statistical Methods , 1964 .

[12]  J. Gray,et al.  Medial septal lesions, hippocampal theta rhythm and the control of vibrissal movement in the freely moving rat. , 1971, Electroencephalography and clinical neurophysiology.

[13]  P. L. Parmeggiani,et al.  On the functional significance of the circuit of Papez. , 1971, Brain research.

[14]  C. Stumpf,et al.  Drug action on the electrical activity of the hippocampus. , 1965, International review of neurobiology.

[15]  J. Gray,et al.  Sodium amobarbital, the hippocampal theta rhythm, and the partial reinforcement extinction effect. , 1970, Psychological review.

[16]  S. Landis,et al.  Afferents to the septal area of the rat studied with the method of retrograde axonal transport of horseradish peroxidase. , 1974, Brain research.

[17]  T. Myhrer.  Normal jump avoidance performance in rats with the hippocampal theta rhythm selectively disrupted. , 1975, Behavioral biology.

[18]  I. Whishaw,et al.  Anterior hypothalamic electrical stimulation and hippocampal EEG in the rat: suppressed EEG, locomotion, self-stimulation and inhibition of shock avoidance. , 1975, Behavioral biology.

[19]  J. Gray,et al.  Sex and strain differences in septal driving of the hippocampal theta rhythm as a function of frequency: Effects of gonadectomy and gonadal hormones , 1977, Neuroscience.

[20]  G. Raisman.  The connexions of the septum. , 1966, Brain : a journal of neurology.

[21]  Ian Q. Whishaw,et al.  Generators and topography of hippocampal Theta (RSA) in the anaesthetized and freely moving rat , 1976, Brain Research.

[22]  P. Andersen,et al.  Two generators of hippocampal theta activity in rabbits , 1975, Brain Research.

[23]  J. Defrance.  A Functional Analysis of the Septal Nuclei , 1976 .

[24]  J. Gray,et al.  Septal driving of the hippocampal theta rhythm as a function of frequency in the male rat: Effects of adreno-pituitary hormones , 1977, Neuroscience.

[25]  J. Gray,et al.  Frequency-Specific Relation between Hippocampal Theta Rhythm, Behavior, and Amobarbital Action , 1970, Science.

[26]  J. Gray,et al.  Septal driving of hippocampal theta rhythm as a function of frequency in the male rat: Effects of drugs , 1977, Neuroscience.

[27]  J. Gray.  Drug Effects on Fear and Frustration: Possible Limbic Site of Action of Minor Tranquilizers , 1977 .

[28]  Vanderwolf Ch.  Limbic-diencephalic mechanisms of voluntary movement. , 1971 .

[29]  U. Ungerstedt.  Stereotaxic mapping of the monoamine pathways in the rat brain. , 1971, Acta physiologica Scandinavica. Supplementum.

[30]  J. Winson,et al.  Patterns of hippocampal theta rhythm in the freely moving rat. , 1974, Electroencephalography and clinical neurophysiology.