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Author (up) Bucher, D.; Buchner, E. file  url
openurl 
  Title Stimulating PACalpha increases miniature excitatory junction potential frequency at the Drosophila neuromuscular junction Type Journal Article
  Year 2009 Publication Journal of Neurogenetics Abbreviated Journal J Neurogenet  
  Volume 23 Issue 1-2 Pages 220-224  
  Keywords Adenylyl Cyclases/*physiology; Animals; Cyclic AMP/physiology; Drosophila/*physiology; Enzyme Activation/radiation effects; Excitatory Postsynaptic Potentials/physiology; Light Signal Transduction/physiology; Miniature Postsynaptic Potentials/physiology; Motor Neurons/enzymology; Neuromuscular Junction/*physiology; Photic Stimulation/methods; Synapses/enzymology/physiology  
  Abstract Photoactivated adenylate cyclase alpha (PACalpha) is a light-activated adenylate cyclase that was originally cloned from the eye spot of the protozoan Euglena gracilis. PACalpha has been shown to rapidly increase intracellular cyclic adenosine monophosphate (cAMP) in vivo in Xenopus oocytes and HEK293 cells, increase the spike width in Aplysia sensory neurons, and modify behavior in Drosophila. Using the GAL4 UAS system, we heterologously expressed PACalpha in motorneurons and quantified the effects of its activation at the neuromuscular junction of the Drosophila third instar wandering larva, a well-characterized model synapse. By recording from body-wall muscle 6, we show that the presynaptic activation of PACalpha with blue light significantly increased miniature excitatory junction potential (mEJP) frequency in the presence of calcium with a delay of about 1 minute. Similar effects have been observed in previous studies that utilized adenylate cyclase agonists (Forskolin) or membrane-permeable cAMP analogs [dibutyryl cAMP and 4-chlorophenylthio-(CPT)-cAMP] to increase presynaptic cAMP concentrations. PACalpha's efficacy in combination with its specificity make it an invaluable tool for the rapid regulation of cAMP in vivo and for investigating the mechanisms by which cAMP can modulate synaptic transmission and neuronal plasticity in Drosophila.  
  Call Number Serial 1255  
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Author (up) Lamm, C.; Batson, C.D.; Decety, J. file  url
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  Title The neural substrate of human empathy: effects of perspective-taking and cognitive appraisal Type Journal Article
  Year 2007 Publication Journal of Cognitive Neuroscience Abbreviated Journal J Cogn Neurosci  
  Volume 19 Issue 1 Pages 42-58  
  Keywords Adolescent; Adult; *Brain Mapping; Cerebral Cortex/blood supply/*physiology; Cognition/*physiology; *Emotions; *Empathy; Facial Expression; Female; Functional Laterality; Humans; Image Processing, Computer-Assisted/methods; Magnetic Resonance Imaging/methods; Male; Oxygen/blood; Photic Stimulation/methods; Questionnaires; Reference Values; Social Perception; Statistics as Topic  
  Abstract Whether observation of distress in others leads to empathic concern and altruistic motivation, or to personal distress and egoistic motivation, seems to depend upon the capacity for self-other differentiation and cognitive appraisal. In this experiment, behavioral measures and event-related functional magnetic resonance imaging were used to investigate the effects of perspective-taking and cognitive appraisal while participants observed the facial expression of pain resulting from medical treatment. Video clips showing the faces of patients were presented either with the instruction to imagine the feelings of the patient (“imagine other”) or to imagine oneself to be in the patient's situation (“imagine self”). Cognitive appraisal was manipulated by providing information that the medical treatment had or had not been successful. Behavioral measures demonstrated that perspective-taking and treatment effectiveness instructions affected participants' affective responses to the observed pain. Hemodynamic changes were detected in the insular cortices, anterior medial cingulate cortex (aMCC), amygdala, and in visual areas including the fusiform gyrus. Graded responses related to the perspective-taking instructions were observed in middle insula, aMCC, medial and lateral premotor areas, and selectively in left and right parietal cortices. Treatment effectiveness resulted in signal changes in the perigenual anterior cingulate cortex, in the ventromedial orbito-frontal cortex, in the right lateral middle frontal gyrus, and in the cerebellum. These findings support the view that humans' responses to the pain of others can be modulated by cognitive and motivational processes, which influence whether observing a conspecific in need of help will result in empathic concern, an important instigator for helping behavior.  
  Call Number Serial 245  
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Author (up) Mayer, K.; Blume, F.; Wyckoff, S.N.; Brokmeier, L.L.; Strehl, U. file  url
openurl 
  Title Neurofeedback of slow cortical potentials as a treatment for adults with Attention Deficit-/Hyperactivity Disorder Type Journal Article
  Year 2016 Publication Clinical Neurophysiology : Official Journal of the International Federation of Clinical Neurophysiology Abbreviated Journal Clin Neurophysiol  
  Volume 127 Issue 2 Pages 1374-1386  
  Keywords Adult; Attention Deficit Disorder with Hyperactivity/diagnosis/physiopathology/*therapy; Cerebral Cortex/*physiology; Electroencephalography/*methods; Female; Humans; Male; Middle Aged; Neurofeedback/*methods/*physiology; Photic Stimulation/methods; Reaction Time/*physiology; Treatment Outcome; Young Adult; Adult ADHD; Cnv; Neurofeedback; Scp; Self-regulation  
  Abstract OBJECTIVE: Attention Deficit-/Hyperactivity Disorder (ADHD) has been treated successfully in children with neurofeedback (NF). In this study, for the first time NF is investigated in adults with ADHD. To answer the question of specificity the relationship between treatment outcome and self-regulation ability is assessed. METHODS: Twenty-four participants underwent 30 sessions of slow cortical potential NF. Measurements of ADHD and comorbid symptoms, as well as neurophysiological data (reaction time (RT) and RT variability (RTV) and contingent negative variation (CNV)) were performed before and after treatment, and again six months after sessions were completed. Participants were categorized into self-regulation learners and non-learners. RESULTS: Significant improvements on all symptom scales were observed with medium to large effect sizes after treatment and six months post treatment. RT and RTV decreased significantly and there was a trend for an increased CNV. Half of the participants successfully learned to regulate their brain activity. In the long-term, symptoms in the group of learners improved more than in non-learners with large effect sizes. CONCLUSION: NF is effective in treating adult ADHD long-term. The impact of self-regulation ability and possible unspecific effects still require further investigation. SIGNIFICANCE: This study is the first to investigate the effects of NF in adults with ADHD, relating clinical outcome to self-regulation performance.  
  Call Number Serial 1297  
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Author (up) Ross, R.S.; Sherrill, K.R.; Stern, C.E. file  url
doi  openurl
  Title The hippocampus is functionally connected to the striatum and orbitofrontal cortex during context dependent decision making Type Journal Article
  Year 2011 Publication Brain Research Abbreviated Journal Brain Res  
  Volume 1423 Issue Pages 53-66  
  Keywords Adolescent; Adult; Brain Mapping; Corpus Striatum/blood supply/*physiology; Decision Making/*physiology; Face; Female; Functional Laterality; Hippocampus/blood supply/*physiology; Humans; Image Processing, Computer-Assisted; Magnetic Resonance Imaging; Male; Neural Pathways/blood supply/*physiology; Oxygen/blood; Pattern Recognition, Visual/physiology; Photic Stimulation/methods; Prefrontal Cortex/blood supply/*physiology; Reaction Time/physiology; Statistics as Topic; Young Adult  
  Abstract Many of our everyday actions are only appropriate in certain situations and selecting the appropriate behavior requires that we use current context and previous experience to guide our decisions. The current study examined hippocampal functional connectivity with prefrontal and striatal regions during a task that required participants to make decisions based on the contextual retrieval of overlapping sequential representations. Participants learned four sequences comprised of six faces each. An overlapping condition was created by having two sequences with two identical faces as the middle images. A non-overlapping condition contained two sequences that did not share any faces between them. Hippocampal functional connectivity was assessed during the presentation period and at the critical choice, where participants had to make a contextually dependent decision. The left hippocampus showed significantly increased functional connectivity with dorsal and ventral striatum and anterior cingulate cortex during the presentation period of the overlapping compared to the non-overlapping condition after participants knew the sequences. At the critical choice point of the overlapping condition, the left hippocampus showed stronger functional connectivity with the orbitofrontal cortex. These functional connectivity results suggest that the hippocampus may play a role in decision making by predicting the possibilities of what might come next, allowing orbitofrontal and striatal regions to evaluate the expected choice options in order to make the correct action at the choice point.  
  Call Number Serial 152  
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Author (up) Taffe, M.A.; Taffe, W.J. file  url
doi  openurl
  Title Rhesus monkeys employ a procedural strategy to reduce working memory load in a self-ordered spatial search task Type Journal Article
  Year 2011 Publication Brain Research Abbreviated Journal Brain Res  
  Volume 1413 Issue Pages 43-50  
  Keywords Animals; Appetitive Behavior/*physiology; Humans; Locomotion/physiology; Macaca mulatta; Male; Memory, Short-Term/*physiology; Neuropsychological Tests; Photic Stimulation/methods; Psychomotor Performance/*physiology; Spatial Behavior/*physiology  
  Abstract Several nonhuman primate species have been reported to employ a distance-minimizing, traveling salesman-like, strategy during foraging as well as in experimental spatial search tasks involving lesser amounts of locomotion. Spatial sequencing may optimize performance by reducing reference or episodic memory loads, locomotor costs, competition or other demands. A computerized self-ordered spatial search (SOSS) memory task has been adapted from a human neuropsychological testing battery (CANTAB, Cambridge Cognition, Ltd) for use in monkeys. Accurate completion of a trial requires sequential responses to colored boxes in two or more spatial locations without repetition of a previous location. Marmosets have been reported to employ a circling pattern of search, suggesting spontaneous adoption of a strategy to reduce working memory load. In this study the SOSS performance of rhesus monkeys was assessed to determine if the use of a distance-minimizing search path enhances accuracy. A novel strategy score, independent of the trial difficulty and arrangement of boxes, has been devised. Analysis of the performance of 21 monkeys trained on SOSS over 2 years shows that a distance-minimizing search strategy is associated with improved accuracy. This effect is observed within individuals as they improve over many cumulative sessions of training on the task and across individuals at any given level of training. Erroneous trials were associated with a failure to deploy the strategy. It is concluded that the effect of utilizing the strategy on this locomotion-free, laboratory task is to enhance accuracy by reducing demands on spatial working memory resources.  
  Call Number Serial 80  
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