A processor-implemented neural network method, the method comprising: during a training of a neural network, calculating individual update values for a weight assigned to a connection relationship between nodes included in the neural network; generating an accumulated update value by accumulating the individual update values in an accumulation buffer; and training the neural network, comprising: determining whether the accumulated update value is equal to or greater than a threshold value at a predetermined update period, wherein if the weight is a fixed point value, the threshold value is a value corresponding to a least significant bit of the weight and if the weight is a floating point value, the threshold value is a value corresponding to the least significant bit of an exponent part of the weight; accumulating the individual update values in the accumulation buffer until a next update period in response to the accumulated update value being smaller than the threshold value; updating the weight using the accumulated update value in response to the accumulated update value being equal to or greater than the threshold value, wherein the updating comprises: determining an effective update value based on the accumulated update value, wherein the effective update value is a portion of the accumulated update value exceeding the threshold value, or a multiple of the least significant bit of the weight, adding the effective update value to the weight, and subtracting the effective update value from the accumulated update value of the accumulation buffer. during a training of a neural network, calculating individual update values for a weight assigned to a connection relationship between nodes included in the neural network; generating an accumulated update value by accumulating the individual update values in an accumulation buffer; and training the neural network, comprising: determining whether the accumulated update value is equal to or greater than a threshold value at a predetermined update period, wherein if the weight is a fixed point value, the threshold value is a value corresponding to a least significant bit of the weight and if the weight is a floating point value, the threshold value is a value corresponding to the least significant bit of an exponent part of the weight; accumulating the individual update values in the accumulation buffer until a next update period in response to the accumulated update value being smaller than the threshold value; updating the weight using the accumulated update value in response to the accumulated update value being equal to or greater than the threshold value, wherein the updating comprises: determining an effective update value based on the accumulated update value, wherein the effective update value is a portion of the accumulated update value exceeding the threshold value, or a multiple of the least significant bit of the weight, adding the effective update value to the weight, and subtracting the effective update value from the accumulated update value of the accumulation buffer. determining whether the accumulated update value is equal to or greater than a threshold value at a predetermined update period, wherein if the weight is a fixed point value, the threshold value is a value corresponding to a least significant bit of the weight and if the weight is a floating point value, the threshold value is a value corresponding to the least significant bit of an exponent part of the weight; accumulating the individual update values in the accumulation buffer until a next update period in response to the accumulated update value being smaller than the threshold value; updating the weight using the accumulated update value in response to the accumulated update value being equal to or greater than the threshold value, wherein the updating comprises: determining an effective update value based on the accumulated update value, wherein the effective update value is a portion of the accumulated update value exceeding the threshold value, or a multiple of the least significant bit of the weight, adding the effective update value to the weight, and subtracting the effective update value from the accumulated update value of the accumulation buffer. determining an effective update value based on the accumulated update value, wherein the effective update value is a portion of the accumulated update value exceeding the threshold value, or a multiple of the least significant bit of the weight, adding the effective update value to the weight, and subtracting the effective update value from the accumulated update value of the accumulation buffer.