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Development of functional connectivity from pre- and parasubiculum to medial entorhinal cortex
e176
Abstracts / Neuroscience Research 71S (2011) e108–e415
Research fund: This research was supported by grants 99-2410-H-002-088MY3 and 99-2218-E-007-002 from the National Science Council, Taiwan, and the Excellent Research Projects of NTU. doi:10.1016/j.neures.2011.07.758
This scheme is consistent with the notion of a hippocampal CA1 function as task-dependent adaptive filter. Research fund: Human Frontier Science Program Award RGP0039/2010; Tamagawa GCOE Program. doi:10.1016/j.neures.2011.07.760
P2-o10 Goal directed modulation of visual areas predicts direction of movement during a complex airplane piloting task Daniel Callan 1 , Mario Gamez 1 , Daniel Cassel 1 , Mitsuo Kawato 2 , Masa-aki Sato 1 1
Department of Computational Brain Imaging, ATR Brain Information Communication Research Laboratory, Kyoto, Japan 2 Computational Neuroscience Laboratories, ATR Brain Information Communication Research Laboratory, Kyoto, Japan
P2-o12 Development of functional connectivity from preand parasubiculum to medial entorhinal cortex Noriko Koganezawa 1 , Cathrin B. Canto 1,2 , Menno P. Witter 1,2 1
Kavli Institute for systems Neuroscience, CBM, NTNU, Trondheim, Norway Department of Anatomy and Neurosciences, Vrije Universiteit medical centre, Amsterdam, The Netherlands 2
Flying an airplane involves considerable perceptual motor coordination and skill. The goal of this study is to determine brain activity underlying performance on a difficult flying task and predict direction of flight from this activity. The task involved piloting an aerobatic plane, to the left or right, though a set of cones (resembling that of the Red Bull Air Race) in a vertical orientation, in a specified altitude range. Within the 3T fMRI scanner subjects (N = 25) were visually displayed a 1st person perspective of flight (X-plane) and manipulated pitch and roll by a control stick. The experiment consisted of flying left, flying right, and baseline do nothing conditions. The performance of flight through the cones (distance to center, distance to target altitude, degrees to vertical orientation) was used as parametric modulators during analysis of the underlying brain activity. Brain regions found to be reflective of trial level performance included the premotor/frontal (motor planning/attention), basal ganglia (action selection) parietal (visual motor integration), and occipital (visual) cortex. Corresponding contralateral occipital and parietal areas were found to differentiate between right and left direction of flight. A second experiment (N = 14) adding passive watching conditions was conducted to determine whether visual activity distinguishing between left and right direction of flight was merely perceptual in nature or if it additionally involved performing the flying task. Decoding over voxels in the occipital areas using a support vector machine revealed that direction of flight could be predicted for the flying task earlier than the passive watching task. These results strongly suggest that attention and goal-directed performance modulate activity in occipital areas and that this activity predicts intended flight direction prior to movement. Research fund: National Institute of Information and Communications Technology and by KAKENHI, Grant-in-Aid for Scientific Research©(21500321).
The entorhinal cortex and hippocampus, as well as the presubiculum (PrS) and parasubiculum (PaS) contain spatially modulated neurons. In medial entorhinal cortex (MEC) there are position-coding grid cells, in hippocampus place cells are found, and in pre- and parasubiculum the majority of spatially tuned cells are headdirection cells. The functional relationships between these cell types are still poorly understood but it is likely that input from PrS or PaS is important for the development and maintenance of spatial functionality of MEC. One way to study the possible relevance of the interactions between these areas and the cell types within, is to look when cells become functional and how this relates to development of connections. Grid cells in MEC develop from P17 onwards, whereas headdirection cells in PrS are already present and stable at that age. We investigated when functional inputs to MEC from PrS or PaS develop by using optical imaging with a voltage sensitive dye (RH-795) in slices taken from postnatal day (P) 5-P30 old rats. First indications for functional inputs from PaS to MEC were present from P9 and onwards. From P11/P12, the pattern of neural activity became stable and adult like. Projections from PrS to MEC were also first observed around P9, providing an excitatory drive mainly, but not exclusively to layer III. From P15 to P16 onwards, the activation in layer III of MEC diminishes and eventually disappears, indicating an increased level of inhibition in layer III of MEC, similar to what has been reported in adult MEC (Tolner et al., 2005). These results indicate that functional connections of PaS to MEC develop between P8/9 and P12, before grid cells develop in MEC. Connections of PrS to MEC become functional slightly later than those from PaS. The observed weakening of excitatory drive of MEC layer III occurs around P15/16 just before grid cells develop in MEC. Research fund: This study was supported by a Centre of Excellence grant Nr. 145993 and a research Grant Nr. 181676 of the Norwegian Research council and by the Kavli Foundation.
doi:10.1016/j.neures.2011.07.759
doi:10.1016/j.neures.2011.07.761
P2-o11 Gamma-band frequency shift during alert immobility in rat hippocampal CA1 area
P2-o13 Enriched environment enhances left-right asymmetry of the hippocampus
, Yoshio Sakurai 3,4 , Yoshikazu Muneyoshi Takahashi 1,2 Isomura 2 , Minoru Tsukada 2 , Johan Lauwereyns 1,2
Yoshiaki Shinohara , Aki Hosoya, Hajime Hirase
1
Grad. Sch. of Sys. Life Sci., Kyushu Univ., Fukuoka, Japan 2 Tamagawa Univ. Brain Sci. Inst., Tokyo, Japan 3 Dept. of Psychol., Grad. Sch. of Letters, Kyoto Univ., Kyoto, Japan 4 CREST, Japan Sci. and Tech. Agency, Kawaguchi, Japan Much research has focused on hippocampal activity during active exploration (i.e., place cell activity). Less is known about hippocampal activity during alert immobility. Our previous study showed that the spikes of CA1 neurons shift approximately half of a theta cycle during a one–second period of immobile fixation, while the rat is fully alert. Based on this finding we proposed a hypothetical hippocampal function as an adaptive filter between entorhinal cortex and CA3, propagating relevant information depending on task requirements. Here, we show additional evidence with gamma-band activity in CA1 area that supports this hypothetical view of hippocampus. Four rats were trained on a delayed spatial alternation task using a sustained nosepoking paradigm. We recorded multi-unit activity and local field potentials (LFPs) in stratum pyramidale of the dorsal CA1 using a 14-tetrode hyperdrive assembly during task performance. Population analysis of the LFPs showed that the gamma-band activity, recorded around stratum pyramidale of CA1, shifted from high frequency (50–90 Hz) at the beginning of fixation, to low frequency (30–45 Hz) at the end of fixation. It is known that the faster gamma rhythm derives from extra-hippocampal regions (e.g., entorhinal cortex), whereas the slower gamma rhythm originates from CA3-CA1 intra-hippocampal circuitry. Thus, these data suggest that the delayed spatial alternation performance is supported via fast-gamma entorhinal input to hippocampal CA1, which is then converted to slow gamma activity for CA3.
RIKEN, BSI, Hirase Unit CA3-CA1 projection in left and right hippocampus has been known to be arranged differently in rodents. For instance, the postsynaptic expressions of some NMDA and AMPA receptor subunits are biased to the lateral origin of the presynaptic cells (Kawakami et al., 2003; Shinohara et al. 2008). Despite accumulating structural, molecular, and functional characterization of hippocampal circuitry asymmetry, how the asymmetrical projection impacts the way hippocampal circuitry works in living animal is largely unknown. We utilized linearly arranged 16-channel silicon probes to record local field potential (LFP) activity from each layer of dorsal CA1 in urethane anesthetized rats. We find that the spectral power of theta associated gamma oscillations in the CA1 stratum radiatum is higher in the right hippocampus. Moreover, the power ratio of bilateral gamma oscillations becomes more pronounced in rats reared in enriched environments. These results suggest that the degree of neural activity synchronization is different in left and right hippocampus and animal’s rearing condition (e.g. visual and tactile experience) is a significant factor to sculpt the left-right asymmetry. Research fund: KAKENHI (21700440), RIKEN SPDR Program funding, RIKEN intramural funding. doi:10.1016/j.neures.2011.07.762
Abstracts / Neuroscience Research 71S (2011) e108–e415
Research fund: This research was supported by grants 99-2410-H-002-088MY3 and 99-2218-E-007-002 from the National Science Council, Taiwan, and the Excellent Research Projects of NTU. doi:10.1016/j.neures.2011.07.758
This scheme is consistent with the notion of a hippocampal CA1 function as task-dependent adaptive filter. Research fund: Human Frontier Science Program Award RGP0039/2010; Tamagawa GCOE Program. doi:10.1016/j.neures.2011.07.760
P2-o10 Goal directed modulation of visual areas predicts direction of movement during a complex airplane piloting task Daniel Callan 1 , Mario Gamez 1 , Daniel Cassel 1 , Mitsuo Kawato 2 , Masa-aki Sato 1 1
Department of Computational Brain Imaging, ATR Brain Information Communication Research Laboratory, Kyoto, Japan 2 Computational Neuroscience Laboratories, ATR Brain Information Communication Research Laboratory, Kyoto, Japan
P2-o12 Development of functional connectivity from preand parasubiculum to medial entorhinal cortex Noriko Koganezawa 1 , Cathrin B. Canto 1,2 , Menno P. Witter 1,2 1
Kavli Institute for systems Neuroscience, CBM, NTNU, Trondheim, Norway Department of Anatomy and Neurosciences, Vrije Universiteit medical centre, Amsterdam, The Netherlands 2
Flying an airplane involves considerable perceptual motor coordination and skill. The goal of this study is to determine brain activity underlying performance on a difficult flying task and predict direction of flight from this activity. The task involved piloting an aerobatic plane, to the left or right, though a set of cones (resembling that of the Red Bull Air Race) in a vertical orientation, in a specified altitude range. Within the 3T fMRI scanner subjects (N = 25) were visually displayed a 1st person perspective of flight (X-plane) and manipulated pitch and roll by a control stick. The experiment consisted of flying left, flying right, and baseline do nothing conditions. The performance of flight through the cones (distance to center, distance to target altitude, degrees to vertical orientation) was used as parametric modulators during analysis of the underlying brain activity. Brain regions found to be reflective of trial level performance included the premotor/frontal (motor planning/attention), basal ganglia (action selection) parietal (visual motor integration), and occipital (visual) cortex. Corresponding contralateral occipital and parietal areas were found to differentiate between right and left direction of flight. A second experiment (N = 14) adding passive watching conditions was conducted to determine whether visual activity distinguishing between left and right direction of flight was merely perceptual in nature or if it additionally involved performing the flying task. Decoding over voxels in the occipital areas using a support vector machine revealed that direction of flight could be predicted for the flying task earlier than the passive watching task. These results strongly suggest that attention and goal-directed performance modulate activity in occipital areas and that this activity predicts intended flight direction prior to movement. Research fund: National Institute of Information and Communications Technology and by KAKENHI, Grant-in-Aid for Scientific Research©(21500321).
The entorhinal cortex and hippocampus, as well as the presubiculum (PrS) and parasubiculum (PaS) contain spatially modulated neurons. In medial entorhinal cortex (MEC) there are position-coding grid cells, in hippocampus place cells are found, and in pre- and parasubiculum the majority of spatially tuned cells are headdirection cells. The functional relationships between these cell types are still poorly understood but it is likely that input from PrS or PaS is important for the development and maintenance of spatial functionality of MEC. One way to study the possible relevance of the interactions between these areas and the cell types within, is to look when cells become functional and how this relates to development of connections. Grid cells in MEC develop from P17 onwards, whereas headdirection cells in PrS are already present and stable at that age. We investigated when functional inputs to MEC from PrS or PaS develop by using optical imaging with a voltage sensitive dye (RH-795) in slices taken from postnatal day (P) 5-P30 old rats. First indications for functional inputs from PaS to MEC were present from P9 and onwards. From P11/P12, the pattern of neural activity became stable and adult like. Projections from PrS to MEC were also first observed around P9, providing an excitatory drive mainly, but not exclusively to layer III. From P15 to P16 onwards, the activation in layer III of MEC diminishes and eventually disappears, indicating an increased level of inhibition in layer III of MEC, similar to what has been reported in adult MEC (Tolner et al., 2005). These results indicate that functional connections of PaS to MEC develop between P8/9 and P12, before grid cells develop in MEC. Connections of PrS to MEC become functional slightly later than those from PaS. The observed weakening of excitatory drive of MEC layer III occurs around P15/16 just before grid cells develop in MEC. Research fund: This study was supported by a Centre of Excellence grant Nr. 145993 and a research Grant Nr. 181676 of the Norwegian Research council and by the Kavli Foundation.
doi:10.1016/j.neures.2011.07.759
doi:10.1016/j.neures.2011.07.761
P2-o11 Gamma-band frequency shift during alert immobility in rat hippocampal CA1 area
P2-o13 Enriched environment enhances left-right asymmetry of the hippocampus
, Yoshio Sakurai 3,4 , Yoshikazu Muneyoshi Takahashi 1,2 Isomura 2 , Minoru Tsukada 2 , Johan Lauwereyns 1,2
Yoshiaki Shinohara , Aki Hosoya, Hajime Hirase
1
Grad. Sch. of Sys. Life Sci., Kyushu Univ., Fukuoka, Japan 2 Tamagawa Univ. Brain Sci. Inst., Tokyo, Japan 3 Dept. of Psychol., Grad. Sch. of Letters, Kyoto Univ., Kyoto, Japan 4 CREST, Japan Sci. and Tech. Agency, Kawaguchi, Japan Much research has focused on hippocampal activity during active exploration (i.e., place cell activity). Less is known about hippocampal activity during alert immobility. Our previous study showed that the spikes of CA1 neurons shift approximately half of a theta cycle during a one–second period of immobile fixation, while the rat is fully alert. Based on this finding we proposed a hypothetical hippocampal function as an adaptive filter between entorhinal cortex and CA3, propagating relevant information depending on task requirements. Here, we show additional evidence with gamma-band activity in CA1 area that supports this hypothetical view of hippocampus. Four rats were trained on a delayed spatial alternation task using a sustained nosepoking paradigm. We recorded multi-unit activity and local field potentials (LFPs) in stratum pyramidale of the dorsal CA1 using a 14-tetrode hyperdrive assembly during task performance. Population analysis of the LFPs showed that the gamma-band activity, recorded around stratum pyramidale of CA1, shifted from high frequency (50–90 Hz) at the beginning of fixation, to low frequency (30–45 Hz) at the end of fixation. It is known that the faster gamma rhythm derives from extra-hippocampal regions (e.g., entorhinal cortex), whereas the slower gamma rhythm originates from CA3-CA1 intra-hippocampal circuitry. Thus, these data suggest that the delayed spatial alternation performance is supported via fast-gamma entorhinal input to hippocampal CA1, which is then converted to slow gamma activity for CA3.
RIKEN, BSI, Hirase Unit CA3-CA1 projection in left and right hippocampus has been known to be arranged differently in rodents. For instance, the postsynaptic expressions of some NMDA and AMPA receptor subunits are biased to the lateral origin of the presynaptic cells (Kawakami et al., 2003; Shinohara et al. 2008). Despite accumulating structural, molecular, and functional characterization of hippocampal circuitry asymmetry, how the asymmetrical projection impacts the way hippocampal circuitry works in living animal is largely unknown. We utilized linearly arranged 16-channel silicon probes to record local field potential (LFP) activity from each layer of dorsal CA1 in urethane anesthetized rats. We find that the spectral power of theta associated gamma oscillations in the CA1 stratum radiatum is higher in the right hippocampus. Moreover, the power ratio of bilateral gamma oscillations becomes more pronounced in rats reared in enriched environments. These results suggest that the degree of neural activity synchronization is different in left and right hippocampus and animal’s rearing condition (e.g. visual and tactile experience) is a significant factor to sculpt the left-right asymmetry. Research fund: KAKENHI (21700440), RIKEN SPDR Program funding, RIKEN intramural funding. doi:10.1016/j.neures.2011.07.762