在PHP中将字符串转换为关联数组

I am using PHP with cURL to make requests to an API.

The API responds with an encrypted string which I then have to use json_decode on and run it through a pre-defined decrypt method that returns a string.

So I have something like this:

echo $response; 
$decodedResponse = json_decode($response, true);

// New instance of Decrypt
$decrypt =  new Decrypt();
$decryptedResponse = $decrypt->decrypt($decodedResponse);
echo $decryptedResponse;

Using var_dump($decryptedResponse) yields string(960) but the string looks like a JSON array.

{"Title":"Mr","Forenames":"Steve"}

So what is the best way to rip apart this string so that I can use the variables through an associative array?

I had already tried:

foreach(decryptedResponse as $data)
{
    echo $data['Title'];
}

But this outputted nothing on the screen.

Am I misinterpreting the use of json_decode?

As many have stated it seems you have to decode twice, I'll look into this and share my findings.