Banca de DEFESA: LUANA DANTAS DA SILVA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : LUANA DANTAS DA SILVA
DATA : 14/12/2018
HORA: 13:00
LOCAL: INSTITUTO DO CÉREBRO
TÍTULO:

GAMMA FREQUENCY DECAY: COMPARING THE ACTIVITY OF RETINA, LATERAL GENICULATE NUCLEUS AND VISUAL CORTEX

PALAVRAS-CHAVES:

Gamma Oscillation, Frequency Decay, Visual System, Retina, Cerebral Cortex

PÁGINAS: 50
GRANDE ÁREA: Ciências Biológicas
ÁREA: Fisiologia
RESUMO:

In addition, the presence of gamma oscillations (30 to 90 Hz) has been implicated in cognitive processes such as perceptual attachment (Singer, 1999; Uhlhaas et al., 2009), attention (Fries, 2001; Gregoriou et al. Pesaran et al., 2002; Montgomery and Buzsáki, 2007) and the temporal expectation (Lima et al., 2011). In the visual system, gamma activity patterns appear at different levels of processing. Gamma activity has been identified as an important mechanism for sensory coding and for controlling the flow of information in cortical-cortical systems, as originally suggested by Pascal Fries (Fries, 2005, Fries, 2009), in his hypothesis of "communication through coherence" (CTC) hypothesis). Recently, experimental work on monkeys has suggested that frequency control may be crucial for neural communication, for example between cortical areas V1 and V4 (Bosman et al, 2012). Furthermore, it has been demonstrated that different frequencies can be used as distinct channels for information transmission, such as between FEF and V4, a mechanism also described in the hippocampus (Colgin et al., 2009). In this way, it is possible that the frequency is a fundamental parameter for the control of gamma oscillations. In fact, some studies indicate that frequency may vary according to the attention load (Bosman et al, 2012). The present study makes comparisons between the gamma generated by very different mechanisms: 1) the retinogeniculate system of the anesthetized cat and 2) the primary visual cortex of the capuchins agreed. We observed a strong decay along the responses in these two systems. Three adult monkeys (Capuchinhos sapajus libidinosus and Sapajus nigritus, male and female) and 4 adult cats participated in this study. Our data shows that the decay of gamma frequency in the primary visual cortex (awake monkey) is surprisingly similar to that observed in the retinogeniculate system (anesthetized cat).

MEMBROS DA BANCA:
Presidente - 1842426 - SERGIO TULIO NEUENSCHWANDER MACIEL
Interno - 1871878 - KERSTIN ERIKA SCHMIDT
Externo à Instituição - JEROME PAUL ARMAND LAURENT BARON - UFMG