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Saif, T.

Publications and source records attributed to Saif, T..

2 recordsLinked to original sources

Tension shapes memory: Computational insights into neural plasticity

Mechanical forces have recently emerged as critical modulators of neural communication, yet their role in high-level cognitive functions remains poorly understood. Here, we present a biologically inspired spiking neural network model that integrates mechanical tension, vesicle dynamics, and spike-timing-dependent plasticity to examine how tension influences learning, memory, and cognitive operations such as pattern completion, projection, and association. We find that increased tension enhances synaptic efficiency by accelerating vesicle clustering and recovery, resulting in a 67% improvement in memory recall speed and a 17% increase in inter-regional synchrony during projection relative to relaxed states. Conversely, a 20% reduction in tension leads to a 31% decline in memory association performance, highlighting the tension-sensitive accessibility of stored information. The model further reveals that networks with 20% inhibitory neurons achieve optimal spatial precision in memory encoding and recall. Together, these in silico findings position mechanical tension as a functional neuromodulator and suggest new directions for neuromorphic design and energy-efficient, living computing platforms. Author summaryOur brains are not only electrical and chemical systems but also mechanical ones. Neurons and their connections are constantly under tension, yet the role of these physical forces in shaping memory and thought remains poorly understood. In this work, we built a computer model of a brain-like network that allowed us to test how mechanical tension influences learning and memory. We found that higher tension improved the speed and accuracy of memory recall, strengthened communication between groups of neurons, and supported more reliable association of memories. In contrast, reducing tension made memories harder to access, though they could be recovered once tension was restored. We also discovered that having the right balance between excitatory and inhibitory neurons was crucial for both storing and recalling information. Our results suggest that tension is not just a background property of brain tissue but an active player in cognition, with potential implications for understanding memory disorders and designing new brain-inspired technologies.

neuroscience↗

Threshold illumination for non-invasive imaging of cells and tissues

Fluorescent microscopy employs monochromatic light which can affect the cells being observed. We reported earlier that fibroblasts relax their contractile force in response to green light of typical intensity. Here we show that such effects are independent of extracellular matrix and type of cell. In addition, we establish a threshold light that invokes minimal effect on cells. We cultured fibroblasts on soft 2D elastic hydrogels embedded with fluorescent beads to trace substrate deformation. The beads move towards cell center when cells contract, but they move away when cells relax. We use relaxation/contraction ratio,{lambda} r, as a measure of cell response to light. The cells were exposed to green (wavelength,{lambda} = 545-580 nm) and red ({lambda} = 635-650 nm) light with a range of intensities. We find red light with intensity less than ~ 57 W/m2 results in{lambda} r = 1, i.e., cells maintain force homeostasis. Higher intensities and smaller wavelengths result in widespread force-relaxation in cells with{lambda} r > 1. We suggest the use of{lambda} > 650 nm light with low intensity (I [≤] 57 W/m2) for time-lapse imaging of cells and tissues in order to avoid light-induced artifacts in experimental observations.

biophysics↗