Calvin K Young

University of Otago · Department of Psychology

Abstract Background The core intrinsic connectivity networks (core-ICNs), encompassing the default-mode network (DMN), salience network (SN) and central executive network (CEN), have been shown to be dysfunctional in individuals with internalizing disorders (IDs, e.g. major depressive disorder, MDD; generalized anxiety disorder, GAD; social anxiety...

Anxiety and panic are both elicited by threat and co‐occur clinically. But, at the neural level, anxiety appears to inhibit the generation of panic; and vice versa. Anxiety and panic are thought to engage more anterior (a) and mid‐posterior (m) parts of the periaqueductal gray (PAG), respectively. Anxiety also engages the hippocampus and medial pre...

Action stopping depends on at least two (fast, slow) frontal circuits depending on the urgency of execution of the ‘go’ response. Human EEG suggests a third (even slower, limbic) circuit that activates frontal areas at frequencies typical of ‘hippocampal theta’. Here we test in male rats whether stop-go conflict engages the hippocampus and so may s...

Head direction (HD) cells form a fundamental component in the brain's spatial navigation system and are intricately linked to spatial memory and cognition. Although HD cells have been shown to act as an internal neuronal compass in various cortical and subcortical regions, the neural substrate of HD cells is incompletely understood. It is reported...

A hippocampal-diencephalic-cortical network supports memory function. The anterior thalamic nuclei (ATN) form a key anatomical hub within this system. Consistent with this, injury to the mammillary body-ATN axis is associated with examples of clinical amnesia. However, there is only limited and indirect support that the output of ATN neurons active...

A hippocampal-diencephalic-cortical network supports memory function. The anterior thalamic nuclei (ATN) form a key anatomical hub within this system. Consistent with this, injury to the mammillary body-ATN axis is associated with examples of clinical amnesia. However, there is only limited and indirect support that the output of ATN neurons active...

Depression is highly prevalent, increases suicide risk, and is now the leading cause of disability worldwide. Our ability to treat depression is hampered by the lack of understanding of its biological underpinnings and of the mode of action of effective treatments. We hypothesised that the scaffolding proteins in the medial frontal cortex play a ma...

Electrical or chemical stimulation of the posterior hypothalamic nucleus (PH) elicits highly adaptive locomotion, demonstrating both evidence of flexibility and variety in exhibited motor behaviours. However, the neural substrates of PH stimulation elicited behavioural changes are poorly understood. The basal ganglia are postulated to be critically...

The posterior hypothalamic nucleus (PH) has extensive anatomical connections to motor, cognitive, visceral, and homeostatic areas of the brain and serves as a crucial subcortical modulator of behaviour. Previous studies have demonstrated that deep brain stimulation (DBS) of this area can lead to powerful activation of motor behaviour, overcoming tw...

Theta oscillations in the hippocampus have many behavioral correlates, with the magnitude and vigor of ongoing movement being the most salient. Many consider correlates of locomotion with hippocampal theta to be a confound in delineating theta contributions to cognitive processes. Theory and empirical experiments suggest theta‐movement relationship...

Theta oscillations in the hippocampus have many behavioural correlates, with the magnitude and vigour of ongoing movement being the most salient. Many consider correlates of locomotion with hippocampal theta to be a confound in delineating theta contributions to cognitive processes. But, theory and empirical experiments suggest theta-movement relat...

Head direction (HD) information is intricately linked to spatial navigation and cognition. We recently reported the co-existence of all currently recognized spatial cell types can be found in the hindlimb primary somatosensory cortex (S1HL). In this study, we carried out an in-depth characterization of HD cells in S1HL. We show fast-spiking (FS), p...

Ethanol is one of the most widely used drugs - with many psychoactive effects, including anxiolysis. The deleterious effects on brain function and general health of chronic and high-level ethanol use are well-studied. However, the neurophysiology of acute low dose ethanol has not been systematically investigated. Here, we examined the effects of lo...

Ethanol is one of the most widely used drugs - with many psychoactive effects, including anxiolysis. The deleterious effects on brain function and general health of chronic and high-level ethanol use are well-studied. However, the neurophysiology of acute low dose ethanol has not been systematically investigated. Here, we examined the effects of lo...

behavioural inhibition, local field potential, theta, beta, gamma, oscillations, stop signal task

Hippocampal (HPC) theta oscillations have long been linked to various functions of the brain. Many cortical and subcortical areas that also exhibit theta oscillations have been linked to functional circuits with the hippocampus on the basis of coupled activities at theta frequencies. We examine, in freely moving rats, the characteristics of diencep...

Algorithms for estimating directed connectivity have become indispensable to further understand the neurodynamics between functionally coupled brain areas. The evaluation of directed connectivity on the propagation of brain activity has largely been based on simulated data or toy models, where various hidden properties of neurophysiological data ma...

Brain oscillations can be used to decode normal and pathological brain function. From the production of simple motor responses to the control of goal-directed actions, synchronous rhythmic activity appears to be important. Stop signal task (SST) modulates rhythmic activity in the right frontal area of a human as a result of activation of the behavi...

Previous studies have shown only modest effects of supramammillary nucleus (SuM) dysfunction on theta frequency and learning in the water maze (WM), with larger effects in other tasks. However, theta recorded from SuM, and used to trigger the production of theta-like oscillations in the hippocampus, produced reversal of the deficit in WM learning p...

Recent studies have shown that electrical stimulation of the posterior hypothalamic nucleus (PH) facilitates locomotion in control rats, and rats were made akinetic by dopaminergic blockade via haloperidol or dopamine depletion by the neurotoxin 6-hydroxydopamine. These findings suggest that PH stimulation might be a promising treatment for akinesi...

Young CK. Behavioral significance of hippocampal theta oscillations: looking elsewhere to find the right answers. J Neurophysiol 106: 497-499, 2011. First published May 11, 2010; doi:10.1152/jn.00358.2011.-The function of hippocampal theta oscillations has been subjected to constant speculation. Dynamic coupling of theta field potentials and spikin...

The importance of acetylcholine (ACh) in higher cognitive functions has been postulated for decades ([Sarter et al., 2005][1]). Attention, arousal, novelty detection, and learning all rely on an intact cholinergic system, which arises principally from the nucleus basalis and the medial septum.

Oscillatory brain activities have been traditionally studied in the context of how oscillations at a single frequency recorded from a single area could reveal functional insights. Recent advances in methodology used in signal analysis have revealed that cross-frequency coupling, within or between functional related areas, is more informative in det...

Deep brain stimulation (DBS) of the basal ganglia motor circuitry is a highly effective treatment for the debilitating motor symptoms of Parkinson's disease (PD). However, recent findings have indicated promising potential for PD therapy with DBS in brain structures outside the basal ganglia. For example, high frequency stimulation of the posterior...

Deep brain stimulation (DBS) of the subthalamic nucleus has been used extensively in the treatment of Parkinson's disease. However, the efficacy of such treatments on bradykinesia/akinesia remains low. DBS of the posterior hypothalamic nucleus (PH) elicits spontaneous, non-stereotypical motor behaviours. We tested the hypothesis that PH stimulation...

Theta oscillations in the hippocampus support cognitive processing. Theta-range rhythmicity has also been reported in frontal and posterior cortical areas--where it tends to show consistent phase-relations with hippocampal rhythmicity. Theta-range rhythmicity may, then, be important for cortico-cortical and/or cortico-hippocampal interactions. Here...

The present study investigated vestibulo-ocular reflex (VOR), optokinetic reflex (OKR) and postural function in patients with rheumatoid arthritis (RA). Compared with controls, no differences in gaze-holding, VOR gain or phase, OKR slow phase velocity (SPV) or quick phase amplitude, optokinetic afternystagmus SPV or duration, or latency to the illu...

INTRODUCTION: Deep brain stimulation (DBS) is the only available treatment for advanced Parkinson's disease (PD) after medications fail. Recent studies have shown the stimulation of other non-basal ganglia nuclei such as the pedunculopontine tegmental nucleus can also ameliorate certain symptoms of PD[1]. One such novel site for DBS is the posterio...